Monday, September 25, 2023


Use your RV air conditioner in low-power situations

By Chuck Woodbury

(BELOW: see the video from RV electricity authority Mike Sokol on how to install the SoftStartRV on a Dometic Penguin II air conditioner.)

As most readers know, we don’t say nice things about a company just to earn money. But I am about to say something very nice, and it’s about a company that approached us about helping promote its product. They were willing to pay us, as a respectful advertiser would. Right now, with our advertising way down due to the pandemic, we were receptive to the idea — but only if the product did what it promised.

The small SoftStartRV™ allows you to run two air conditioners on a 30-amp hookup (you’ll need two devices to run both at once), or one air conditioner using only the power of a small portable generator like a Honda 2000 or 2200. We know from experience that this is a big deal on a hot summer day.

You can even run one air conditioner on a 20-amp hookup. The next time you park in the summer in your RV in a friend’s driveway with only household power available you’ll at least be able to run one air conditioner (13,500 BTU maximum). If you need an extension cord it should be of good quality, at least 12 gauge, no longer than 50 feet. The SoftStartRV™ makes this possible.

Here’s what the SoftStartRV lets you do:
• Run two air conditioners (with 2 SoftStartRVs) on a 30-amp hookup.
• Run one air conditioner using only a small portable generator.
• Run one air conditioner on a 20-amp household hookup.
• Run an air conditioner or two using your onboard inverter system.

The first thing I did was have the company send a device to our RV electricity expert Mike Sokol of If Mike were to report back to us that it was junk, then we’d have nothing to do with the device or the company. However, after testing it, Mike said it did everything it promised, and that it was a game changer for RVers. You can see his video below.

Here, very simply put, is how the SoftStartRV™ device works:

When you turn on the air conditioner in your RV, there’s a huge jolt of power needed to get it to start. That’s why you hear a loud thud right when it’s kicking in.

But only moments later, its need for power drops dramatically to about 13-14 amps.

What the SoftStartRV™ does is manage the start-up power surge so that it doesn’t hit at once, but gradually, avoiding the huge power spike. That’s why you can run two air conditioners on a 30-amp hookup (with two SoftStartRVs), which you could never do before because of that spike. Ditto running one air conditioner with only the power of a small portable generator. With summer coming, obviously, this device can make a huge difference in your comfort.

So, that’s our story about our relationship with Network RV, the manufacturer of the product. Now, you may want to watch this short video from Mike Sokol that tells more about how the device works. As most of you know, Mike will absolutely not be associated with anything that does not live fully up to its promises.

If you want to learn more, visit our special page at the SoftStartRV™ website where you can get a discount if you decide to buy one or more of the devices.

Take a couple of minutes to watch this video by RV Electricity expert Mike Sokol for an electrician’s explanation of how the SoftStartRV™ works.

Watch Mike’s Sokol’s video with instructions for installing the SoftStartRV on a Dometic Penguin II air conditioner:


  1. The peak inrush current on my 15,000 BTU unit dropped from a generator stalling 76 Amps down to 26 Amps when I installed one.

  2. My 40 year career was in HVAC & Refrigeration. Based on the schematic, it appears to be nothing more than a potential relay / start relay set up which I used throughout my career… however, I do see a “start capacitor” already mounted in the unit… I installed a “hard start kit’ on my home AC 20 years ago, and as advertised in this video, it dramatically lowers the in rush current. That bothers me is one of the commenter noted it would shut down his generator after a few minutes, as the compressor run time,, would slowly raise the amperage draw which I found over the years is highly indicative of “solid state” energy savers. Am I wrong ? As I am planning to buy a toy hauler in the next few months, I am very curious

    • Totally different from the hard start kits we used in the HVAC business. One day when I have nothing else to do I plan to put a couple of current probes on my oscilloscope and see what each winding is doing during startup. I suspect that the device varies the phase shift to the start winding. Interesting thing is that it learns the motor over several starts and it comes down after each start until it gets down to a minimum. On my 15,000 BTU peak inrush went from 76 Amps before installing the device. After installation peak dropped to about 50 on first start, then dropped on each restart until I stopped checking it after 6 starts. 6th start had 26 Amp peak inrush.

  3. Already made one comment, this is 2nd. Years ago, A long long time ago (20 about) my husband noticed that 30 amp was only needed to “start” the AC on the camper, but that the running amps were much lower. I sure wish he would have thought of that device back then. What a amazing Idea.

  4. What a cool Idea. I am disabled and cannot get on the roof, do you know any legit shops around Sachse, Texas that might do this?

      super honest reliable mobile Rv service. Called him on AC unit that had died. Didn’t expect it to be under warranty but they did the leg work and had it replaced in a week. Very pleased with him and his wife for Great response and service. He is based in Princeton. Pretty sure he could install for you. Good luck Mike

  5. I am thinking the 13,500 btu Coleman on my popup runs off a dedicated 20 amp breaker. One year, my breaker panel went out on a hot camping trip. Luckily, this popup’s ac unit was plugged directly into this dedicated 20 amp wall outlet inside the camper – it wasn’t hardwired to the panel. I got a hd extension cord, ran it to a 20 amp 110 outlet on the pedestal, and had ac all week (but no other electricity). I’m just not clear how soft start helps on a single ac unit on a 20 amp outlet (most house outlets have 15 amp breakers). Why would it help me? Can it run an ac on a home’s standard 15 amp outlet?

    • I think it would be a close call. Just don’t let someone convince you to install a larger breaker without having a professional electrician make sure the wire is rated for the larger breaker. There is a good reason the codes regulate breaker sizing and it involves fire trucks.

  6. Be realistic in deciding. A generator loses 3+ percent of output for each 1,000 feet of altitude. At just 3,000 feet altitude, the generator loses over 10 percent of its output. At 5,000 feet altitude, my 2000 generator wouldn’t even run the microwave.

    A 15,000 BTU AC plus the RV inverter can draw more AMPs than a 2200 generator can produce even at low altitude. Reducing output for altitude, it’s uncertain.

    A Honda 3000si generator produces only 23.5 AMPs (sea level), which may be barely enough. Some might call a 3000si a “small” generator, but at 150 pounds, that’s too heavy for most people to carry. At high altitude, even a Honda 3000si might not produce enough output.

    • MANY DO IT, simply have to limit to the 3600 watts vs 12000 watts; THE CG POLE CIRCUIT BREAKER does that. Can work just as easy as the 30a popup.

  7. I believe people confuse what the reality is of this product. The running amps will not drop the only change is the inrush or starting amps.

    • Correct. Also be aware there are different companies with this device. I believe MicroAir is original with the EasyStart.

  8. I have wondered about this for some time now but can’t seem to find info for an application on our basement a/c in our 2008 Winnebago Tour DP. Recommendations? Thx

    • call the coleman folks. they will walk you through how to install the unit and which sift start they prefer. they will know if this one will work or the other is best

  9. I have a new Ford F-150 with the “power on board” inverter accessible from the trucks bed. The “power on board” is rated at 2K watts (max). I have a single domestic 13.5k A/C on the roof AND the trailer is rated at 30AMP max.
    Question; Will the “soft start” provide a soft enough start up surge to allow the AC to start and run? I’m talking about at sea level.

  10. I have a 2015 VV on our last trip north I installed the soft start system since I knew we would be staying at a couple of friends houses. We plugged into both of their garage circuits 20 amp. At both locations we kept tripping the breakers. This was what I hoped the soft start would avoid. Things don’t always work like they claim

    • I contacted the manufacturer with this same question 2 years ago and they did not have a suitable device for 230 volts compressors at that time. I have probably same problem, my 8500 watt home backup generator overloads when my 3 ton unit tries to start. I designed a controller that delays the fan motors from starting until the compressor inrush current is over and it is working for me. Thought about building the controllers and selling them but too much liability involved. But you might make a go of it.

  11. I checked with Airstream online, they did not recommend it. Has anyone received a written & signed “OK” from Dometic in case your A/C is under warranty ?

  12. I believe the article is a bit optimistic. I’m in the process of installing an SS. One 2000 generator will not run a 15,000 btu AC. Plus, at altitudes, you lose 3+ percent of power for every 1,000 foot gain.

    To the guy who mentioned screw-on connectors, please give me a link. I’m having the same trouble you had, major pain. I wish SS included those in their kit.

  13. Sounds more like a paid endorsement. The original works better , has less issues, better support & the latest upgrade is Bluetooth so you can troubleshoot & see what’s happening. MICROAIR Easystart 364. I swear I’m just a customer.

  14. Just hooked my soft start up this week. Ran great while at home (off standard house outlets and off my brand new Honda EU2200i. First day on the road, overloaded the Honda in 5 min. After some troubleshooting, the draw, which had been 1350 at the house, is starting at 1600 and creeping up to 1800+ before overloading the generator. If I keep the shroud off the ac, it settles back down to 1500ish and does fine. But with the shroud on, I think something is heating up and drawing too much power? It’s about 80deg outside. Any ideas? (Oh, btw, I have probly run the ac for all of 10 hours EVER. Bought the camper last year, and just running ac for the first time now)

  15. I installed two on the motor home, one on the toy box. So far AOK.
    EXCEPTION – One unit gave me trouble because of the “Crimp” style splice caps. Replaced those with “Screw-on” type, problem solved. I knew better than to use the crimp types from my working days but thought maybe things had improved, they haven’t. Our factory started sending the crimp-on types with the equipment. They caused UNENDING problems. We trashed them and returned to screw-on type.
    Word to the Wise.

  16. This is yet another upgrade that should be already installed in all new RVs. Why don’t the RV air conditioning manufacturers include these in all their A/Cs? Can’t wait for the European DC 12-volt units to take over

  17. Btw it’s not true you can’t run your RV air conditioning off of 15amp house circuit. I do it all the time running our Dometic ac off of exterior house outlets.

  18. We have two Soft Starts and have been on the phone with tech support for hours (literally) at various times the past month. They can’t figure out and admittedly had to do more research as to why we can’t run our two a/c’s at campgrounds with 30 amps nor with our 3500w generator. Even with everything turned off except the soft starts, the breaker is kicked in minutes. We have two 15kw units on our 2020 Montana.
    Honestly, I hate the things because it’s so blame hot and it’s nothing but trouble trying to see if they’ll work at each location.
    The tech on the phone went through every step with my husband to make sure they were hooked up correctly (they were.) Still no answer in sight and the last tech person hasn’t returned with an answer.
    We do know some of the older campgrounds have 30 amp that don’t actually throw 30 amps but that’s never mentioned and doesn’t explain why they don’t work with the generator.
    Now we’re waiting to get the amps our a/c’s actually use to see if that’s it.

    • I would check the draw on you RV with every breaker turned off but the main breaker, should be 0 amps Then turn one AC breaker on start the AC and check the Ampere draw and note the draw, then turn off the first AC and do the same to the 2nd AC noting the ampere draw, the combined draw should not exceed the 30 amp rating or 3600 watts. Turn on only the AC breakers and try starting one then the other. Just a note, My 60amp converter/charger draws 1000 watts or approximately 8 amps. If you are using lights and charging your batteries while plugged in you need to figure this into your total Amperes/Watts. Refer on electric 300watts/2.5 amps, water heater 1440 watts/12 amps. Run whatever you can on gas to limit you electrical draw.

    • I’m having the same problem. I almost wish I had never purchased my SS. I’m tired of climbing up on the RV roof. I have a Montana too.

    • This watts where wattage comes from. I would wire the second unit to a line plug and not overload the 15 amp. You might only have one strong 30 amp, near the stove. As well, unplug the microwave till you need it. It’s on the same plug.

  19. I installed soft start based on many reviews that a 15kw air conditioner would work with a 2000 watt inv. generator. Mine only ran for 2-4 min then shuts down (Honda 2000i). Contacted soft start. they say you need a minimum of 2200W, a 2K won’t work. I then tried a 2200W Generac, lasted less than a minute. Any thoughts?

    • My experience with SS has been positive. Two Coleman 15kw heat pumps with a seperate SS for each. Two Honda 2000 ‘s with companion kit. 95 degree day. Both running at same time with no problems when cycling on and off. Both HP’s are original to 2006 Tiffin Phaeton and are not upgraded energy models. All that being said the problem might be related to the internal wiring in your RV. Also ran fine when using onboard diesel gen.

    1. Do you have to know the serial/model number of the AC’s you’ll be installing this on? If so, is climbing up on the roof and removing the covers the only way to get this number?
    2. We are thinking, at minimum to install it on the main living area AC, and we have a Honda 2000i generator will this work, will it start the AC and keep it running? We often camp at high altitude, so what affect will this have? Thanks.
  20. I’m not sure I understand this sentence – …’re out of luck if you want to run two air conditioners (with two SoftStartRVs). That is, unless you have a state-of-the-art SoftStartRV……. we bought a SoftStatRV with the discount thru here last year. Are you saying there is now a better SoftStartRV? that ours is outdated?

    • Sorry, Heather. It was misworded. It’s been corrected. I don’t think your SoftStartRV is outdated. Have a good day. 🙂 —Diane

  21. I don’t understand this…I can run my AC on the house 120 without this device. I can also run it on my 2000w inverter and 1000w solar panels (granted not for a long time or after the sun goes down. Haven’t tried it on my 2500/2200w genny. Am I missing something here?

  22. I found softstart useless in practice… can ONLY rub the AC on undersized generator and can’t run AC long on inverter. I sold my 2KW genny and got a 4KW like you SHOULD do in my case.

  23. My 98 Bounder had an Intellitech load management system so 2 A/C’s could run on 30 amp service. My 2006 Tiffin Phaeton is 50 amp and has 2 15kw heat pump units with a SoftStart in each unit. The onboard 7.5 kw Onan runs both with no problems.
    After installing the SoftStarts I hooked up 2 Honda 2000’s with factory parallel cables. On normal/high power they ran both A/C’s on a 90 degree day with no problems. Next on the same 90 degree day I put the Honda’s on eco and got same results. The SoftStarts do excatly what they claim. No big surge of electric needed to start or run 2 15 kw heat pumps on 4kw of power.

    • I wonder if you could run just one AC with just one of your Honda 2000’s? We have a 15k AC and don’t think, even with the Softstart that we will be able to run one AC with our Honda 2000.

    • Wait ! you had a 98 Bounder and you could run both A/C’s on 30 amp … how we have a 2000 and are having trouble running one A/C

    • Hi, Richard. I’m not sure of the answer to your question. But it’s apparently fairly easy to install the SoftStartRV yourself. Here’s a link to Mike Sokol’s recent Ask the Expert video on YouTube, where Danny Rahner, from SoftStartRV, explains how to easily install the product: Take care. 😀 —Diane at

      • OK. I see Mike keeps saying the price is 250.00USD but the website shows it is on sale for 299.00. Is their a discount code for RV Newsletter members that I missed?

  24. The only issue I had using my cheapo Champion 2000w generator was that I could not start the a/c if the generator was running in eco mode. Once I bumped it up to ‘normal’ speed it had no problem running the a/c. Best investment I ever made (well, almost).

    • Hi, Steve. Thanks for your question. Here is a link to a recent Ask the Expert episode on YouTube with Mike Sokol and Danny Rahner from SoftStartRV with the easy installation procedure: Also, here is the link to their support page, which includes their phone number: Maybe you can phone them, or send an email (“support ticket”), with your question. Good luck! 😀 —Diane at

  25. I have a jayco 145rb that has what amounts to a compact window ac unit in the wall….a PD-8K-AC. I also run the Honda 2200 generator and it can’t react quickly enough to run it in eco mode. Will the soft start fit in one of these?

  26. Is it feasible to install a “central” SoftStart that can be shared between two AC units that are never engaged simultaneously?

  27. Mike, my 2020 Airstream International has two A/C’s and fifty amp power. Will I need one “soft start” unit per A/C ? Thank You.

  28. I have a problem when I am using my microwave and my air conditioner kicks in the breaker gets thrown on the hookup pole. Will this help in my situation.

    • Yes, it likely will help stop tripping the breaker when the air conditioner kicks in. I assume you’re on a 30-amp shore power connection.

  29. I installed the soft start on my Dometic 15,000 BTU heat pump. It worked fine for a few months. The RV sat on the driveway through a heat wave (120 in Palm Springs) and after that the AC would only blow room temperature air. Not sure if the intense heat caused a problem with the Soft Start or the unit itself. Having an RV Tech. diagnose today. Since the Dometic units are pretty much disposable (This is the second one I’ve had fail in three years) I’m guessing the unit will have to be replaced. Trying to decide if I should install the soft start (assuming it is not the problem) in the new unit… Do you know if exposure to the heat could cause an issue with the soft start?

    • I don’t think that normal heat will affect a SSRV unit, but I’ll leave that question for Danny Rahner from SSRV to answer.

  30. Hello I’m so happy to be able to post here today. I in fact added this product to our new 2020 Cherokee 24js. I had an issue that my 3400w Champion would not run the A/C, it would over load instantly. We installed the unit, it only took 2 try’s well no one said i was an electrician. We just had to put the Red wire back on the starter. Ok with that said IT WORKS great. Ran the A/C on high ran the TV,lights an Microwave all at the same time. Thank you folks great product is performed as advertised

  31. Why are you recommending the Honda 2200? The link you provided shows that unit has 15 amp outlets, the softstart needs 20 (for a single AC). Why not the Generac gp3000i. ? It has 20amp output and is less expensive as well.

    • Note that a 15-amp receptacle can provide up to 20-amperes of current as long as the circuit breaker is rated for 20-amps. I’ve also used a Honda EU2200 Companion generator which has a 30-amp twist lock outlet, but it can only provide 18 amperes of current from the inverter.
      As far as brands go, you pay your money and make your choice. Honda is the gold standard for Inverter generators, but there are other quality products on the market as well. As long as it’s a quiet inverter generator I’m okay with it. But please don’t bring an open-frame contractor generator to a campground as that won’t make you any friends at all due to the noise.

    • It goes into your A/C unit that sits on top of your RV roof. You remove the cover and you will see the components that make up the air conditioner. This unit installs right beside them and then you cover it all back up again with the cover.

  32. So you can run 2 AC units on a 30 amp with these as I understand. Can you run 3 AC units (2×15,000 1×13,500)with 3 of these on a 50 amp service?

  33. Chuck,
    Soft Start product sounds great and I am really interested. However reading recent reviews on Amazon there are several customers, of Soft Start, that were not able to get Soft Start customer service to respond to their calls. If I purchase the Soft Start product Customer Service for me “is the product”. Thoughts or insights?? Thank you.

    • Steve, I had the opposite experience. I was able to contact customer support quickly. I even scheduled the time to work through the installation. You need to know that I am very slow and methodical BEFORE I ever make a step in an installation, so I checked with them and double checked with them. They answered the phone and were extremely supportive each and every time I called. Just call SoftStart tech support: Danny (915) 235-6056.

      • This same product was just used in my home during the install of my new whole house unit. The tech said it makes the compressor last long,

        • Interesting that you mention the home unit. While getting our HVAC unit serviced last year the ‘tech’ said he will eventually replace the compressor on MOST A/C units because they take a beating everytime they start up. I asked about the SoftStart unit for my home A/C. He’d never heard of it . . .

    • Best customer service from a tech and purchase point of view. I had small issues that we resolved entirely by the company. These folks provide excellent effort in problem solving and support. Ask for Danny.

      • Third consecutive day in a row. I’m actually running my ac on 20 amp plug at brother-in-laws house. Also during a boondockerswelcome excursion late last week the same thing. Low power on 20 amp breaker with a 15 amp adapter. No problem. This is a game changer in how we decide where to go nowadays.

    • Thank you folks for the response. I will be contacting Soft Start about my situation. I have a 2018 Newmar with two Dometic Air Conditioners with Heat Pumps. I haven’t seen anything concerning air conditioners with heat pumps. Again thank you for the feedback

      • Heat pumps are essentially the same as straight A/C units – there’s just some additional internal valves to reverse the coolant flow. Same compressor load in either mode of operation so the Soft Start should work fine.

      • Hello Mike. Did you try the SoftStarRV with power from an inverter?
        If so, what size inverter, a/c draw and battery capacity?
        Very interested in results and conclusions. Thanks, Gerard

        • I did try this with a 2,000-watt Hybrid Inverter provided by CarGenerator, and it worked great for as long as the batteries lasted. More on just how much battery power you need to run an air conditioner soon.

  34. can I get this shipped to Canada? I was trying to order one and there doesn’t seem to be any way to enter a Canadian address.

  35. In my 1998 Fourwinds Windsport, I ran two AC’s on 30 amp by basically doing exactly this but manually. My unit had a front and a back thermostat. When I would first power them up, I just turned on one first then the other. I don’t think I ever had issue where they both attempt to start at the exact same time being the temps would change at different paces between the front and the rear of the RV. Had it happened, it just would not have started until it tried to cycle again. The ONLY time it needs that power is during startup as the article says.. Once the unit is running, the power draw drops dramatically.

    During the day, we just shut down one unit and closed the master bedroom area. At night, we power both on but they run a lot less of course. If on Genset, we ran both as it supplied plenty of 50 amp power.

    • If those are the original A/C’s those don’t pull as much amperage as the newer ones do to them being low pressure as the new ones now are high pressure. So that’s probably why you’re getting away with it

    • My ‘99 Bounder ran 2 A/Cs off 30A service by somehow controlling 1 A/C at a time. If the front A/C was running the bedroom unit was off and Vice versa. Never fully understood how it did it but it worked.

  36. What is the difference between the Micro-Air and the Soft Start RV? From what I can figure, they are virtually identical.

    • I know that Soft Start Rv has one more wire, so there must be one. That said, from what I have read, Micro-Air has live tech support by calling and SoftStartRV you have to enter a ticket online and wait for them to call you back. No phone number.

    • I’ve not done a full round of experiments with the Micro-Air unit yet, but the main difference seems to be that the Micro-Air Easy Start needs you to cycle the air conditioner 5 times to learn its starting characteristics, while the SoftStartRV has a built-in factory current envelope ramp. That’s the major difference that I’ve seen so far.

  37. I called carrier and they said my Mach has this feature built in. Is that true. It may be redundant. 2013 model

    • I’m not sure. If Carrier will send me one I’ll be glad to put it on the lift and do a quick HRDL test. I won’t even have to open the hood.

  38. Hi Mike and all ,
    Based in South Africa.
    Just bought my first RV and starting my first revamp and looking to upgrade my solar system, which will be a 5000w inverter system, will this Soft Start work directly off the solar system.


    PS will these guys ship to SA.

      • We work off a 220 but In the RV I have the option of 12v ,24v and the solar.
        I contacted a few outdoor stores, most had never heard of soft-start ,LOL
        its going to great expensive shipping it in , but the best is worth it.

  39. Interesting information. I have gone without AC for years while keeping my small class A stored at home in between trips. All this got me thinking.. if it takes a 70% surge just to get the AC to start running.. can I start the AC with the onboard generator and, once it is running (on low) keep it going on household power (extension cord)?

    • That is an interesting question. You probably have at least a 3,000 watt generator on your small Class A. I understand that the automatic transfer switches (like mine) have a sensor priority where, if two power sources are available, The generator power source wins.
      So in theory, you could start the A/C with your generator, be plugged into Shorepower, then turn off your generator.
      I really have no idea on what the effects would be any electronics running (such as an A/C unit).
      Mike? Any advice?

    • Highly unlikely this will work in the long term unless you plan to keep the A/C unit running continuously 24/7 after it starts including all night long. You would have to set the thermostat to it’s lowest setting to get that to happen and even then the system might cycle. The current surge occurs every time the compressor starts, not just the first time.

  40. I have a Coleman Mach 8 AC Heat & pump. I am told that it already has 3 capacitors and I do not need the Soft Start. Coleman said if I install it, it is redundant and may cause a fire. Comment?

  41. Comment on a brand new installation of the SoftStart.
    Wow was this simple. I routed the wires into the “box” that houses and protects the Run capacitor. Connected the wires, just like the instructions direct. Went into the RV and turned the main breaker back on, and started up the A/C.
    Honestly a simple and easy installation.

    • Yes it is. And I used WAGO connectors for the hookup so I can easily swap back and forth between the SoftStartRV and stock starting capacitors. I love those WAGO connectors compared to wire nuts.

  42. Question about the SoftStart. Mike, if we have the SoftStart installed on our A/C unit, I am hearing that we are NOT able to utilize our portable 30amp Surge Protector that we plug into the Power post. Have you found this to be true? (note: I just installed my new SoftStart but have not traveled with it yet.)

    • Note: I am running a test right now with my 30 amp surge protector connected to 30 amp shore power pole. So far the A/C with the newly installed SoftStart is working. I will continue to monitor it but it is currently looking like the “advice” I heard is not correct.

      • Great Question Alan. I don’t think I would have thought of it before I buy & install mine. Thanks for posting this and I hope all goes well during your testing process.

    • That’s not true. In fact, a SoftStartRV unit will reduce the voltage drop considerably when the compressor is starting, which should reduce any Advanced/EMS surge protector shutdowns.

    • I don’t think that’s true. However, I can easily run a few experiments later this month while doing my Hughes Autoformer test and try out several EMS/Advanced surge protectors from Progressive, SurgeGuard and Hughes Power Watchdog. I’m sure that a SoftStartRV won’t affect the operation of any surge protector, but I’m willing to do a bench experiment.

  43. I am about to buy a Honda eu2200i, and was wondering if anyone has had experience starting a 15,000 btu a/c with a SoftStartRV unit installed?
    Any insights would be appreciated!

    • I have the eu2200ic (the companion to yours). The advertised spec’s say it will provide 18.5amps. I ran my 13,500 btu A/C with it. I am not sure of the required amps for your 15,000 btu unit.

      Your eu2200i is rated at 15 amp output.
      I looked up the Dometic 15,000 btu rooftop A/C unit, and it looks like it might require 15 amps. That is within the output of the eu2200i , from the literature anyway.

      (Note: The math was: 115 volts divided into 1,725 watts = 15 amps.
      Mike and others can correct my bad math)

  44. I’ve installed the softstart on my rv with 1 single 15K BTU AC. Since the install, I can’t run the AC with 2 Yamaha 2000iS generators in parallel. Part of this may be because of my inverter and batteries as the inverter/charger pulls a fair load if the batteries are low. I need to do more troubleshooting.

    • Call Dan at SoftStart – (915) 235-6056. He is a wealth of knowledge. He told me about issues with inverters/protectors, although I don’t actually understand it all. (not a EE degree person myself)

  45. I have done a little research myself. I can see this so called soft start costs between 1/4 to 1/3 of the cost of a new air conditioner. In fact it costs more than a small house window air conditioner. Having seen the inside off the unit in question there are less parts than inside of a radio. I have to conclude that the $299 price tag is to pay for the R+D of this thing. Having work in the electronics field for over 40 years I can tell you with absolute certainly this thing is way over priced. I can buy a lot of gasoline for a generator with $300 dollars instead of what this thing costs. The $300 is a serious drawback for what it is. This looks like a good plan for air conditioner manufacturers to install in their units at a far less price.

    • You always pay research and costs with any product.. a 299 dollar unit is cheaper than a larger generator or not having g a second ac when you need it. It’s also supply and demand.

  46. Can this help me when I’m experiencing what seems(we’re assuming because a voltage meter we have plugged in shows dips below 110) to be low voltage from my camp grounds, I had an RV guy come check it my trailer, he said everything inside including my power cord is operating correctly, but my AC won’t stay running more then 10 mins and we’re experiencing 110°+ days right now, I only have one ac a 30amp trailer

    • Liw voltage can play havoc with ac units. This is common as I’ve seen with voltage below 108V. Below 104 is very bad for your ac unit.

  47. I bought and installed one of these units on my RV and it works exactly as advertised. I can run one of my AC units off a little Honda 2000 generator with no issues.

  48. Mike, what is your take away from this statement from edd over a month ago “I run two A/C’s w/o a soft start. Run the 1st with temp set as low as you can, 65. After it stabilizes start the second. The A/C runs at about 13 amp X 2 = 26 amps on a 30AMP circuit.” Curious as to whether or not this act will damage an a/c unit?

  49. How hard is it to hook up? Could a rv handyman hook it up or do I need an electrician. Easy to understand instructions?

    • I installed the unit on my AC. I am a pretty good handyman but you do not need to be an electrician. And I had a question and contacted the mfg. and they were VERY helpful! Took me maybe an hour!

  50. What is the difference between the SoftStartRV and the Micro-Air Easy Start. I note the Micro-air needs 5X runs to allow the unit to “Learn The System” before it is ready to perform the normal running operation?
    Also will the SoftStartRV work with a Coleman 7000 Ducted Roof 13.5 K BTU unit? I have a 1997 American Eagle Class A motorhome.

  51. I own a 1978 GMC Royale Motorhome that came with two factory-installed roof air conditioning units. Unfortunately, the way it was wired was that you could only use one at a time. The circuit breaker panel would switch between shore line power or generator power. Each was on a 30 amp circuit. By installing two SoftStart devices (one on each air conditioner) and rewiring the loads, I am able to run both air conditioners simultaneously from either circuit. That is much appreciated as I live in Arizona where the summer temperatures sometimes reach 120 degrees fahrenheit.

  52. The SoftStart unit cost is 10X that of a Capacitor that the A/C manufacture parts departments will sell you, they have Kits for around $27, where as SoftStart guys want to sell you their units for $299.

    • That’s not true. These intelligent soft start units work on a different principle than a standard starting capacitor. ALL single-phase air conditioner compressors use a starting capacitor of some sort that will draw 5 to 10 times the continuous running current during the startup cycle. The aftermarket hard start capacitors you’re referring to tend to draw even MORE current during the starting cycle which might help jump start a compressor on a low voltage shore power line, but will overload a portable generator even more than a factory capacitor. I’ve personally measured the SoftStartRV unit and found that it limits the startup current to around 2x the running current by chopping the starting current and spreading it out over a longer length of time (1/2 second or so). Starting capacitors can’t do that, which is why why they tend to overload small generators and trip circuit breakers already running close to capacity. I know because I’ve run these experiments myself.

  53. I have a 5200 watt Onan on my class A it has a dedicated 30 amp circuit to the factory ac. I have removed the forward vent and installed Dometic Cool air II it is wired to under the RV to plug in on a 20 amp plug at pole. I also have it wired into the RV on a separate circuit next to the pole plug in, That runs off the 20 amp breaker of my generator but only run the fan while in motion. Could I use this on my 20 amp circuit when it’s all that is plugged in on that side, and run my ac while driving???

  54. Mike, upon initial reading, I was extremely excited, thinking this is exactly what I need when parked in the driveway. You say this can run a 13.5 btu on a regular 20a household circuit. With the exception of my kitchen outlets and other outlets requiring high amperage, my “regular” outlets are only 15 amps? Any solutions or am I out of luck?

    • Well, here’s the secret of 15 vs. 20-amp outlets. Most of them have exactly the same amount of contact area inside. And if you look at any 15-amp plug you’ll see its contacts have exactly the same surface area as a 20-amp plug. So if there’s a 20-amp circuit breaker and 12-gauge wire feeding a 15-amp outlet, it’s actually rated for 20-amps of current. There’s an exception in the code as well as UL allowing this, so don’t worry. If you’re on a 20-amp breaker with 12-gauge wiring, then you have a 20-amp circuit, even if it’s using a NEMA 5-15 outlet.

      • I read the reply and I would NOT want a 20 amp 12 ga. extension cord on a 120VAC 15 amp breaker in the House Panel, most of which have 14 ga wire, 15Amp. 1500 Watt Max load.. 120 x 20 = 2400 Watts. If the 15Amp breaker is replaced with a 20 Amp,The wiring would become the fuse! Max on a DEDICATED outlet,. Which needs to be a GFI ! A 20 amp outlet is Not the same as a 15. And outside with 14ga run to it ? And $299 x 2 = + tax is a huge investment.
        Are the units you advertise tested on GFI circuits? GROUND wires are NOT grounding wires. It mentions that after Start most Air Conditioners run under 15 Amps. Would it be possible to list the Air Conditioners that RV mentions with those specs? Thank You so much.
        On a side note, does RV believe in and explain Power Surges that do not trip breakers?

        • Lee, I’m not sure exactly what you’re saying. I’ve noted above that a NEMA 5-15 receptacle has exactly the same contact area as a NEMA-5-20 receptacle, so if it’s connected to a 20-amp circuit breaker with 12 gauge wire, it’s capable of supplying 20 amps of current. I’ve never said that 14 gauge wiring can be upgraded to a 20 amp breaker. Where did you read this? Do you have any test data, code text or close-up photographs to support your 5-15 outlet theory?

          I’m also confused about your statement on GFCI Ground wires not being grounding wires. What is your point? GFCIs don’t need a ground wire at all to operate. I know that some older air conditioners can develop small amounts of ground-fault leakage which can randomly trip a GFCI, but I don’t think that’s what you’re saying. Please explain.

          And can you clarify your statement “does RV believe in and explain Power Surges that do not trip breakers”? I”m not sure what that means? Are you talking about thermal/magnetic breaker curves?

  55. I installed one on our Jayco trailer and it didn’t work with one Honda 2000i kept tripping the overload on the generator. Worked with their service tech and it’s wired correctly and does work with a shoreline and both my 2000i’s Hondas coupled together. Yes the Hondas are putting out their maximum wattage.

    • Not sure. You should contact tech support as mine starts a Dometic Penguin II 13.5 kBTU air conditioner on my Honda EU2200 generator easily.

      • I did work with with their tech support on the phone we went over everything and came up with no answer. I’m a plumbing contractor with 33 years in the trade so I have a little skill in installing equipment. I have 2 Honda 2000i tried them both (one at a time) with them same results trips the overload. The A/C works great on shore power or the 2 Honda’s coupled together.

  56. Mike, has there been any research into possible damage to the compressor due to the slow start up while using the soft start equipment?

    • Only anecdotal evidence that there’s no damage. In fact, it might reduce long time wear and tear on the compressor due to less starting stress. Time will tell…

      • Mike, I was under the impression that Fast Start add-ons to AC systems was for just that, to reduce the heat generated from slow starts because of typical lower capacitance on systems. Heat equals wear and tear on the motor windings, and slow start ups weren’t necessarily efficient because it generated higher currents (higher than the running current) for longer periods of time, thus costing more in energy bills over time. Not that the RVer pays the electric bill, just the rent…

        • A note from the Amazon ad for the fast start add on, example:

          The cost of a 5-2-1 Compression Savor is a fraction of the cost of replacing a compressor damaged by hard starts. It could add years to the life of your compressor and other electrical components associated with your A/C system.

  57. Mike, I believe you should compare the SoftstartRV to the Micro air soft start.i purchased the Micro-air 364 soft start and installed it on our Coleman ducted 15000 btu ducted AC on our 5th wheel. Last week I received the SoftstartRV that I ordered from your link. I installed the SoftstartRV on our front Domestic Penguin 13500 btu non ducted unit yesterday. I’m interested in a comparison to both units when you get your testing equipment up and running. I did notice a big difference in what SoftstartRV sent me for installation and what I received from Micro-air. Installation instructions were harder to follow on the SoftstartRV video as I could not find any Utube videos on the SoftstartRV where there are numerous installation videos on the Micro-air.

    • It wasn’t too complicated for me to do the SoftStartRV install, but I’m on my bench and have read thousands of schematics in my 50 years of doing this sort of thing. But yes, I would agree that installation videos are a great help.

  58. I just had my SoftStart installed yesterday and it works like a charm. My cheapo Champion 2000 watt generator runs the a/c in our Arctic Fox travel trailer with no problems.

    • It should help get the compressor started, but running any air conditioner at 100 volts for extended times will tend to overheat the compressor and is not recommended by any of the air conditioner manufactureres.

  59. I run two A/C’s w/o a soft start. Run the 1st with temp set as low as you can, 65. After it stabilizes start the second. The A/C runs at about 13 amp X 2 = 26 amps on a 30AMP circuit.

  60. Regarding the SoftStart, we have been trying to have the company get back to us to discuss our problems installing the 2 units. According to my electrician, the instructions are confusing, at best. We have spent the last 2 days trying to figure out the issues. Soft Serve was of no help to us. While they acknowledged our call, they have yet to get back to us with assistance. We are leaving for a month long trip, in a few days, and I know that several of our campsites only have 30amp service.

    • Ed McMullen, They will contact you today. All we have heard for months is that the installation is easy — and that has been our experience, too.

    • Thanks for the kind words, John. We all (staff included) appreciate them — and you! 😀 —Diane at

  61. When are you going to do the follow up on the Micro air Easy start? In the first review there was mention of May 31st 2nd review.

    • I need to figure out a quick disconnect plug for the Dometic air conditioner that will allow me to plug in an EasyStart, SoftStart, or the original hard-start capacitor at will. Shouldn’t be too much longer but I have to be careful not to damage anything. Plus I don’t have my new data gathering setup in place. Yes, I have to invent a way to measure all these controllers at sufficient resolution to be relevant. Rather than capture data at 5 times a second with two decimal place accuracy as I did last week, my new monitoring system will capture it up to 96,000 times a second with PPM (Parts Per Million) accuracy. I could calibrate a nuclear missile guidance system with this new test rig I’m building. And yes, I actually used to do just that.

    • Airxcel ,Colman-Mach told me if you install the Softstartrv on any of their air conditioners it will void the warranty.

  62. Any generator starts to lose power as you gain altitude…I think it’s 3.5% for every 1,000 feet above 3,000 feet…give or take. Also, outside air temperature affects a generator’s operation. So, a hot day combined with high altitude may have your gen struggling EVEN with one of the easy start devices. That said, having one of these installed still makes it easier on your AC components than without.

    I ran my Honda EU2200i at 4,000 feet on a 100*F day and after about 5 minutes of run time after the compressor kicked on the Honda would cut out for about a second sending the AC/Easy Start back into the 5-minute start up mode as the Easy Start is designed to do. It would do that continuously and we were just barely able to cool the interior. A table fan was essential.

    Other than that, it’s a great add-on for camping at lower altitudes. Even with 30-amp hookups the device puts less wear and tear on your AC.

  63. Let’s say you’re running your 15,000 BTU AC off a household 15 or 20AMP (120volt) outlet with one of these installed, using a short 12 gauge power cord. Everything is running smoothly but you haven’t tried using the microwave or a vacuum cleaner or other high power device with the AC on yet. Would you be even able to? I know every setup is different, but typically, with the setup I’ve described, is it possible or would it be too much? Is it safer to just turn off AC while using other high powered devices?

    Which brings me to my important follow-up question, what happens when it IS “too much”? Generally, what happens? Does AC get damaged? Does your RV’s electrical system? Or does your household breaker (and/or) RV breaker just trip and everything shut off? Things don’t get permanently damaged in general when you overload, right?

    Thanks, again, new to RV’ing

    • Sorry, I just saw this. The answer is that when running from a 20-amp outlet you can only have ONE high current appliance on at a time. Trying to use the microwave or vacuum cleaner while the air conditioner is running won’t work for more than a few seconds before it trips the circuit breaker. The good news is that nothing will be damaged (unless you do this hundreds of times in a row). This is exactly how circuit breakers work to protect wiring from too much current. And you would be asking the wiring the carry too much current. So if you trip a circuit breaker, then you need to not use that combination of appliances. Of course, if you had an intelligent EMS surge protector with a voltage and amperage reading, you can see exactly how much amperage you’re pulling from the outlet.

  64. After reading about it here I ordered one for my RV. Easy install and now I can run my AC off the 20 amp outlet in my driveway. The kit includes everything you need. The only problem I had was the grommet that the wires have to pass through needed to be larger. It would be nice if they included a larger grommet in the kit.

    • I’ve only done a bench test on the SoftStartRV as of yet, but just reading the sales info it appears that the Micro-Air EasyStart works just the same way.

    • I installed the Micro-Air Easy Start before I found out about this one. From all descriptions it sounds like they’re the same. My Micro-Air runs the 13,500 BTU AC just fine with our Honda EU2200i.

    • I installed a micro-start last yr. and use a Westinghouse 2200/2500 inverter generator which has worked every time on my 13.5 a/c. My 1800/2000 Champion generator won’t do the job. It sure would try but no luck. Works on my 20 amp circuit at home.

      • Not all generators are created equal, and Champion watts don’t seem to equal Honda watts, as the saying goes.

  65. I’m an {bleeped} concerning anything electrical. I understand the purpose is to reduce start up load to reduce amperage needed to start the AC. My question is whether that translates into any reduction (again I realize it’s only start up) that could result in utility savings? I see no mention of that so I’m assuming it’s insignificant?

  66. I am truly interested in reading Mike’s evaluation of the Easy Start and comparing it to the Softy Start. I have a Lance trailer and Easy Start is an advertiser on the Lance Forum giving purchasers a discount.

    Now, my real question is this. If these after-market devices are so good, why aren’t they installed on the air conditioners at the factory? Why are they NOT included as part of the initial construction of the air conditioners? Is there any detrimental or adverse effect on the air conditioner over time?

    • There are a lot of things the RV industry doesn’t add to their units. Many dealers are perfectly happy to add them at the buyers’ request. Many RVers make little or no attempt to camp at other than full service RV parks and camps so they’d have no need for this option.

    • It really is a cost thing. There’s a fair amount of control and power circuitry in these soft-start controllers, so they will always cost a lot more than a $10 hard-start capacitor. Plus when air conditioners were first introduced to RVs there were no inverter generators to worry about, and campgrounds were not filled to capacity with RVers needing air conditioning. Take a look at my RVelectricity survey which shows that 59% of RVers have 1 air conditioner, 30% have 2 air conditioners, and 5% have 3 air conditioners. That kind of usage was never anticipated when rooftop air conditioners made their debut.

  67. Does Softstart allow better performance including less ware & tear or any benefit on a RV AC unit that is hooked up to the appropriate power source?
    Or is this product strictly assisting low power source start-ups on RV AC units?

    • My reading indicates that these units make cranking up the AC on initial start easier since it’s a gradual ramp up, not the huge surge your normally hear. My guess this would be less stress on components.

  68. I can’t I woke up this morning and read this. Yesterday I was asking about boondocking because RV parks are so expensive but I disregarded it because of my Dalmatian (Jasper💙). He’s always been an indoor dog so without A/C it just wouldn’t work. This made my day👍🏻!

  69. I realize this new product, SoftStartRV, is awesome, but I would also like to acknowledge another companty who has had their product out for years with great results; MicroAir Soft Start. Right now they are having a summer sale. I believe it is nice for folks to have choices to compare against.

    If I didn’t already have a MicroAir Soft Start, I would consider SoftStartRv after some of my own research about the company and their products and customer service. Though, getting a thumbs up from Mike Sokol, pushes the SoftStartRV up to the front of the line. 🙂

  70. The question is, who can install these for you? A significant number of RVers are not able or comfortable enough climbing on the roof and or working with ac wiring.

    • Since ladder climbing is now in my rear view mirror (ahem), I called a local mobile RV repair guy who says he’s installed several of these SoftStarts. He’ll be here on Thursday to install, and says it will be less than $100. I’m gladly going to pay him while I watch him from the ground . . .

  71. These devices need a means to sequence the startup of two AC/Heat Pump units and other heavy AC loads so that more than one can startup at the same time and trip the 30A breaker. Otherwise this will happen when both thermostats activate at the same time…

    • I not an expert but what about staggering the thermostat setting on each AC a couple of degrees. Wouldn’t that do the trick?

  72. Just installed my 2 SoftStart units. 85 degree day with bright direct sunlight and no clouds. Hardest part of the job was being up on the roof in those conditions. Turned my generator on (Onan 7500 diesel) and genny did not even groan with 2 15 kw heat pump units turning on. Really could not even hear the compressor kick in. Will try with 2 Honda 2000 units yoked together-4kw -and see what happens. VERY satisfied so far.

  73. I have been looking at capacitors for a year and not ready to pull the trigger with all of the experiences others have shared.
    After seeing this option and Mike’s video, I ordered two of them. This will allow me to use 30amp sites in the summer and more options to run both AC units in my trailer keeping it cool faster.
    I also boondock at NASCAR races (when they allow fans again ) so I can run both AC units on my predator 3500 inverter generator.
    Shipping is really quick on these too.
    Don’t let the price drive you to inferior options.

  74. Are they saying with this device installed it is now possible to run your roof AC while connected only to 120 volts household power? Without the need for a 240 volts power?
    Thanks (am new to RV’ing)

  75. I just watched Mikes article on the soft start kit for the A/Cs. Having been in the HVAC industry for fourth years I totally get and agree with his conclusions regarding the soft start
    I would however caution that if your RV is running two A/C units and you have a residential refrigerator you may exceed the “running load” amps of a 30 amp breaker. And even if the breaker doesn’t trip you could be doing irreparable danger to either or all three of the items in the RV
    I’m right in the middle of this scenario right now. With the two A/Cs running, 26 amps, turn on the refer, 33amps
    So be careful, the damage caused can be long term and not surface immediately

    • David,
      I agree that a residential refrigerator can push you over the 30 amp limit with 2 AC running. I purchased one of those Wye power cords that lets you plug into both the 30 amp and 15 amp outlets on the power post for a theroectical 45 amp supply. What are you thoughts? Whenever I use this Wye cord connected to my Progressive power monitor, it does not work. And I am chicken to hook up the Wye cord directly to my rig without the Progressive unit inline. Are there multimeter checks I can make at the power post to insure the campground has wired both the 30 amp & 15 amp power post outlets properly?

    • David the other side of that as I understand is that if your unit has a house fridge in it, it is also wired to run off battery, run it off the battery and you will reduce the draw to 30 amps,, As I understand it and I may wrong

      • Yes, the best solution is to run your residential refrigerator from an inverter powered by your battery. However, if you have a pass-through inverter it will automatically switch to shore power if available, so that would defeat this trick. But most RVs I’ve seen with a residential refrigerator use a dedicated inverter, so that should work as you describe. The problem is that there’s so many different ways RVs are wired, and residential refrigerators come in all flavors and sizes.

  76. I have two Champion 2000 watters I bought at Costco years ago so I could stack them to run the AC. It’s such a pain to haul two generators around, I just don’t do it. We open the windows for ‘air’. But now, with this soft start thing, I’m revisiting the air conditioner possibility. I know Honda is the benchmark for a generator but is there a reason one of my trusty old Champions wouldn’t work with this?

    • Enjoy the Champion gennys. I bought 2 and kit many years ago and used them a lot. Gave them to my brother 3 years ago and in use 5 days s week. 2 years ago bought 2 more. Change the oil and they go forever. The only 2 differences are Honda was 1st with a good product the reason they are best known AND you can buy 1 Honda for the price of 2 Champions with the kit.

    • I’ve discussed the issue of “generator watts” with a number of system designers over the years, and in many cases we’ve determined that there’s no official measurement protocol. So a generator manufacturer can make up most any numbers they like for marketing literature.

      This reminds me of audio amplifiers and loudspeaker power ratings. I’m in the pro-sound business so for me a 1,000 watt loudspeaker may cost upwards of $1,000 to $3,000 or even more. Same for pro-grade power amplifiers which I could use to weld metal if I needed to. However, you can find consumer and car speakers and amplifiers with basically the same ratings on paper for 1/10 or even 1/20 the cost. The difference is real watts vs. imaginary watts. Pro units can produce and use that power for hours on end. I have a number of Tannoy T300 monitor speakers that begin to get happy with a 1,500 watt (real watts) amplifier. Now this cabinet weighs a lot because there’s a single dual-concentric loudspeaker inside with the biggest speaker magnets I’ve ever seen. And the T300 is costly at over $3,000 a pop. But they sound stunning and will put out an amazing amount of sound on a professional stage. I can get Peavey monitor speakers for 1/10 the cost of the Tannoy and it will do basically the same thing. However, I’ve blown up a bunch of Peavey speakers over the years, but have never wrecked a Tannoy.

      This it alos reason that every rental house I know of has a bunch of Honda inverter generators for rent. They’re highly sought after by professionals because we know they won’t let us down if we ask them to do more than they’re rated for. Honda power ratings are very conservative compared to their marketing literature and they seem to run forever. Now I know that everyone wants to save money on a generator, so I’m constantly being asked about Harbor Freight Predator generators. While they look good on paper, I’m just not sure how they stack up to Honda generators in the long run. I’ve asked Harbor Freight for a demo Predator generator to test, but so far I’ve received no answer. As I’ve noted many times, I have zero budget to purchase test products, so unless they’ll send me one to try there’s no way for me to test it. But I do have all the proper load backs and measuring gear for such a test if I ever get the opportunity.

      • Mike, I’ve long had a belief that I’d never buy anything from Harbor Freight that had an electrical cord attached. But after watching a bunch of videos of guys testing and comparing the HF gensets to Honda (of course, none with YOUR expertise. Just guys like me trying to compare the different mfg’s), I bit the bullet and bought the 3500 generator (the quiet one, not the job site one) and have so far, been totally satisfied. I also just bought the Soft Start a/c thing. Once I’m convinced it works as advertised, I’ll sell my 3500 Preditor, and one of my Champion 2000 watters. I know there’s no substitute for quality (Honda being the benchmark), but if my cheapo Champion fills the bill, so be it. I may end up selling ALL the non-Hondas and BUY one Honda – and be done with it. I appreciate your input on all things electrical – especially Gaffer Tape – ha.

  77. Mike I have a 16’ Casita with the 6000BTU AC that is factory installed in the lower closet. I have a 700 Watt Costco Propane Generator. Would this work with that set up? If not what’s the minimum size Generator I would need? Thanks.

    • That’s a big maybe, but I don’t think so. I have started and run a similar sized wall mount air conditioner from my little Honda EX1000 generator that my dad gave me, and it worked well for that. But I assume that your Costco generator is an inverter model, correct? If so, it could be a little sensitive to startup currents and might just trip. So if it does work at all, I would guess that you need to have everything else powered off. The best way to know for sure is to do a little experiment, even if it’s laying the air conditioner on a few 2×4’s next to the RV, plugging into the generator, and giving it a try. I say it’s a 50/50 coin toss. If won’t start the air conditioner reliably on that generator, then it’s possible that a SoftStart on your air conditioner would help. But you should contact tech support to see if they have any history of that sort of installation.

    • Since the 6000BTU running amp is around 5A, but the starting amper is third time more, so your 700W is not enough to power up, use new model 2200VA HONDA was recommand

  78. I had a similar soft start device installed last year. They are well worth the money. The AC no longer thumps when coming on. All you hear is the fan coming on. My 3500 watt champion generator would get a overload on my AC after running for about 15 minutes. This solved the problem.

  79. There is obviously more to these $300 units than the $8 starter capacitors, but has MikeS ever tested the “cheapie” soft-start options? I’m curious how *much* better these are at 30X the cost…

    • I’m working on it, but I do understand the physics. A hard start capacitor draws even more peak current for a shorter duration to start an induction motor connector to home or campground power. But it’s the peak current that shuts down inverter generators. The soft-start technologies slowly ramp up the current over the first second of start up, limiting the peak current, and preventing the generator from going into overcurrent protection mode and shutting down. They work in totally different ways. As to “how much better” that’s really not in my technical vocabulary. I’m an engineer and a scientist, so I can only report the data that I observe as it relates to a hypothesis. Then I go for peer review confirmation by my colleagues.

      • Thanks… sounds like a start capacitor might help with a smaller traditional generator or weaker line power, but not so much with inverter genny overload (which is where this $$ unit would come in)??? In that case, it sounds like maybe inverter gennies should react slower to *brief* overload since starting an RV AC is a very common usage case(?).

        “How much” — I get your vocabulary objection, but it was an open question for unseen effects. I was thinking things like “those cheapies don’t help at all” or “they get the compressor running but can still damage the windings” or whatever… Not expecting “37.2% better!” LOL

        • Yeah, my best RV buddy Gary Bunzer would always tell me there’s no “bad” generators or batteries, just poorly engineered ones. And my EE teachers would never let me answer a question with a yes or no. I had to be ready to defend my answer with the math and needed to show my work. I don’t know enough to say definitively how well these soft-start controllers work, which is why I’m experimenting and reading everything I can on induction motors and compressor theory.

  80. This device only delays the starting of the fan motor to allow the compressor motor to spin up to speed first, then it allows the fan motor to start up. So it does reduce the initial start-up current surge somewhat.

  81. This might be worth considering even for a 30amp/1 ac RV. If your ac is drawing 14 amps and you need another 5-10 amps for ac startup surge, that is most of your available power. A SoftStart or equivalent could free up all or most of those surge amps to be available to run other things.

  82. Do I understand correctly…. whether the AC (with a soft start) is started with a generator/inverter or 30 amp or 50 amp it makes no difference … correct?

  83. Sounds like a big help with a 30 amp connection and 2 AC units. So, how hard it is to install one on an existing AC unit?

    • Seems pretty simple as you can see from their website. Plus they’ll provide virtual help (via your smartphone camera) with the installation if you get into trouble.

    • I am in no way shape or form an electrician. I was able to DIY install mine in an hour or so following the simple instructions. Most of that time was spent climbing up and down my ladder getting tools.

  84. All modern Winnebago rigs I am aware of are wired to allow running two AC’s on 30 amps by controlling the start-up timing of each unit, preventing them from trying to start at the same time.

    • Many of them do, but also many 30-amp breakers at campgrounds are a bit “tired” and can benefit from reduced air conditioner starting current.

  85. A person can buy a whole new air conditioner for that cost. Are there any small centripetal compressors a/c on the market. I studied about them well over ten years ago. They do not have as high of start current draws as the compressor type presently in use, and a lot quieter because of less vibration . IMHO

    • I don’t know if you’re talking about soft-start. Are you asking about soft-start motor controllers, or swing-compressor refrigerator technology.

  86. I have 3 ACs in my 5th wheel. Is it necessary to purchase 3 Softstarts (one for each unit)? I normally only run 1 AC when when I’m on 30A shore power. Would i be able to run 2 ACs using Softstarts?

    • That is the idea, for you to run (start) a second A/C unit on 30 amp power cord or breaker. But if you do, then you have to be miserly with any additional load as you will be close to maxed out on the 30 amp breaker. Also, this is when you start getting overheated connections, so be wary.

      • Yes, that’s true. Anytime you have a continuous heavy current draw you have to really watch your connectors for signs of overheating.

    • You should be able to start and run 2 AC’s on a 30-amp shore power connection or 3,000 watt inverter generator if you install a SoftStart on each AC. However, you will still need to watch additional energy usage in your RV. So no more high-power appliances such as your microwave or hair dryer while both AC’s are running.

  87. I purchased Easy Starts for both my AC units. (The other guys) Easy start has great customer service. They responded to my install question within an hour on Sunday! Works fantastic! Pretty much eliminated all the startup surge and now you cant even hear the compressor start.

    • All true. Instead of the AC’s starting with a bang, they sound like they’re spooling up more gradually. I’ve asked my AC builder contacts if this reduced power surge might increase the life of the compressor, but there’s no definitive data yet. We shall see….

  88. Is there any difference between this and the micro-air Easy Start?

    They are both similarly priced and install in basically the same way.

    • They seem to be very similar in operation, but I haven’t tested them side-by-side yet. Stand by for a full report from me in about a month.

    • They are similar in functionality but the Soft Start guys offer a 90-day free trial, a free 2-year warranty, plus free shipping.

    • Look where they’re made. The Soft Start is made in New Jersey and NOT from China that’s killed people worldwide with the Wuhan Flu. Don’t buy from China they’re the reason you’re in quarantine.

  89. I have a 15,000 btu AC unit and a 2000w generator. It would appear that I am just outside of the range of this unit.

    • SoftStart claims success with 15,000 BTW AC’s on a 2,000 watt inverter generator. But be aware that not all inverter generators are created equal. A Honda is the gold standard (and priced like it), and in many tests it out performs the various wanna-be 2,000 watt knock-off generators from other companies. I’m building a new test shop this summer that will allow me to do those types of comparisons. But money is tight so I have to do these tests a little at a time. However, I do have all the technology as well as the technical chops to do that sort of independent lab testing. In fact, that was my background when I worked for big industry back in the ’70s and ’80s.

    • It might just work given conditions. Even with the soft start device, it struggled to run my 13.5 BTU AC at 4,000 feet on a 90* day. That’s more the fault of the generator losing 3.5% amps per 1000 feet of altitude. You might do just fine at sea level on an 85* day. But give the company a call…they’d have a better answer.

    • I have installed the EasyStart on my Dometic 15k BTU AC and it will start and run using my 15+ year old Honda 2000 watt generator. The generator is fully loaded but it works. The newer Honda generators are 2200 watts so they have a little more margin

      I’m at sea level here and have no experience with it at altitude.

  90. Curious, if you have a device already shedding power requirements like in our Grand Design, would it have to be adjusted or removed? I would think it would say “that second A/C requires XXX amps, so I won’t turn it on, because I don’t understand an easy start.”

    • Will,

      I’ll try to answer. The load shedder in your trailer will continue to do it’s job without a problem. I’m not sure I understand the quoted part of the question but maybe I can simplify an answer. Most of the modern a/c units installed in rv’s these days already feature a more delayed starting circuit so you should probably be fine with what’s in your rig already. Many residential wall or window mounted units have hard starting capacitors in them and it’s easy to hear the thud when they work (if you have lights on you’ll see a temporary dimming of them).


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