Can an RV’s 2-way refrigerator (electric/propane) be converted to a 3-way fridge, to be able to safely run it while traveling? I have a 2022 Winnebago Micro Minnie, 2225RL. Thank you. —Thomas
First of all, I applaud you for researching the safe way to travel by having the propane cylinder shut off. I do not know of any kits or upgrades available to convert a refrigerator to a 3-way. Three-way means it will run on propane, 120-volt power, or 12-volt house battery power with a 12-volt heating element.
From the specification on the Winnebago website, the standard refrigerator for the Micro Minnie and your model was a 10.3 cu. ft., 12-volt compressor-driven refrigerator. The option was an 8 cu. ft., gas/electric model. I’m still a fan of the gas/electric. It is better suited for dry camping, even if you’re not boondocking for weeks on end, just like the option of using the LP for an overnight here and there. I would assume the 8 cu. ft. model fridge was installed at the time the dealer ordered it, as the 10.3 cu. ft. models were in short supply at the time.
Seminar attendees have also asked about converting the RV fridge
In several of my seminars I have gotten the same question. Some have even suggested just installing an inverter that would draw power from the house batteries and provide 120-volt power to the refrigerator and charge the house batteries from the tow vehicle alternator. Sounds interesting; however, I contacted my “go to” expert when it comes to anything electrical, Mike Sokol, and it’s not that simple.
Mike indicated your RV fridge would probably pull at least 600 watts, as his tests have shown, and possibly more when running. Yes, a 1500-watt inverter could handle it. However, your battery/batteries will not. Also, the engine alternator through the 7-pin adapter could not provide enough power to keep the batteries charged after about 1 hour. Even if you had 100 ah lithium batteries, they would discharge in one hour.
So, to answer your question, there is no simple or inexpensive way to upgrade or redesign your refrigerator to be powered by the tow vehicle charging system going down the road.
Mike suggested maybe swapping out the current refrigerator with a Dometic 12-volt model with Danfoss compressor. He has tested that and it only draws a small amount of 12-volt house battery power that could be replenished by the tow vehicle while driving. Check out his review here.
The only issue with the 12-volt model is you do not have the luxury of propane when dry camping, so you will need to find a way to recharge the battery/batteries. According to the Winnebago website, your rig should have had a 190-watt solar panel and 30-amp charge controller standard. You will need to do some calculation on what size battery you have and what other items might be running. But you have a good foundation for using solar power to recharge your batteries when dry camping. You may need to add another panel. I would suggest looking at a portable model so you can park the rig in the shade and put the portable out in the sun. You rig also came with a plug-in charge port mounted to the side of the rig just for these.
Another option is to shut the refrigerator off and shut the valve off at your DOT cylinder. This suggestion typically gets quite a few comments. However, I did tests on both Norcold and Dometic and brought the unit down to 34 degrees. I used a remote thermometer to see what temps occurred. Over a 6-hour period, they were both at 40 degrees. Plus, it was about 90 degrees inside the rig.
Of course, this was without opening the door and with a little help. I put two 5-pound bags of ice in the freezer and some already cold food items inside. You will not be able to cool the unit down to 34 and put warm items inside and expect the same results.
This was a Norcold. The Dometic actually performed better as we had a 9v circulating fan inside it.
Dave Solberg is a leading expert in the RV industry and author of the “RV Handbook” as well as the Managing Editor of the RV Repair Club.
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