Dear Dave,
The camper that we just bought only has one battery, but it has two air conditioners. The person that had it before us was always on shore power. Does this sound correct? I feel they removed a battery. We will be boondocking. What are your thoughts? Thank you. —Elaine, 2014 32-ft. Sundance 5th wheel
Dear Elaine,
Most travel trailers and 5th wheel trailers do not come with a standard battery from the RV manufacturer. Rather, there’s a “travel” battery that the delivery company uses to get it to the dealer. Then the dealer spec’s what type of battery is best suited for the buyer depending on how they are going to camp. If the first owner was going to be plugged in almost all the time, the dealer would not put in two high amp hour batteries. Instead, they would install one cheap deep cycle battery, as the converter would provide 12-volt constant power when plugged in and the battery just acts as a go between.
Keystone’s SolarFlex system
Having said that, Keystone now has a standard feature called SolarFlex™, which is a solar panel, inverter, and lithium battery system that is standard. Depending on the size of the rig, they start with a 200-watt panel and two 100 Ah lithium batteries and go all the way up to 600 watts and 600 Ah batteries, all standard. The larger system allows the owners to run a roof air conditioner for about 3 hours on the high Ah batteries.
However, since your rig is almost 10 years old, it did not come with this and most likely had the standard flooded lead acid (FLA) battery or batteries installed by the dealer initially. And, since it is almost 10 years old, I would assume the battery you now have in your rig is a third or fourth generation one and the previous owner may have bought the cheapest model available.
Deep cycle house batteries don’t power roof air conditioners
Just to clarify a few things, the deep cycle house batteries do not power the roof air conditioners in most cases. The SolarFlex system has a very large battery bank that the high-watt inverter draws from and provides 120-volt power to the roof air conditioners. You will not be able to run your roof air conditioners even with two batteries. You will need to be plugged into a 120-volt source by either a campground pedestal or a generator.
If you are going to be doing any type of boondocking, I would suggest getting acquainted with what components run off 120-volt power and what use 12-volt DC and how much. This will help identify how many amp hours you will need, which depends on how long you plan to be “off the grid.” There are many articles here at RVtravel.com that go into more detail with calculators and such, but I would start with an understanding of the 120-volt components which are listed on this worksheet.
Then take a look at the 12-volt components listed here.
A good resource is the Solar Calculator from Go Power!, which has a list of components and a calculator for how many people and how long you plan to dry camp. It’s not a perfect science but a great start. You can find it here.
You might also enjoy this from Dave
What is the best battery setup for boondocking?
Dear Dave,
Can you help draw up a new house battery system for me. I want to do a lot of boondocking, and don’t want to run the gen set a lot to recharge. My house charger is pitiful—undersized. And I’d like to also install PV panels on the roof. I have four 6-volt Trojan deep-cycle batteries, which went south this year and won’t take a charge. Would appreciate all you could do for this disabled veteran. Thank you. Semper Fi. —Bruce, 2015 32-foot Precept Jayco Class A
Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”
Read more from Dave here.
HAVE A QUESTION FOR DAVE?
Send your inquiries to him using the form below.
##RVDT2414
Add a soft start to your A/Cs to help reduce amperage required to start the A/C. You might be chasing a dream.
Even if you did have a battery setup that you could use while boon docking, it would not make sense to power your air conditioning via the inverter/batteries. The air conditioning would use so much power that your batteries would be consumed in a short period of time, leaving no power for the remainder of your boon docking trip and needs. Even with a solar system, the ratio between power consumption of air conditioning and power production of solar panels, just does not provide enough power to run very long.
Thank you, Dave! 🙂 More great information and so patiently delivered! 🙂 Thank you for sharing your knowledge ! Have a great day and SAFE travels! 🙂
I would not recommend trying to run an AC on battery power even with an extensive solar setup. It would consume too much battery power in a very short amount of time. If a person is going to be boondocking in hot weather, they may as well plan on using a generator when needed for AC.
Agree. Just another thing to increase the cost of our toys. And what would it cost you if your pets died.
Air conditioning and boondocking are like Democrats and Republicans. They don’t play nicely together!