Powering a 2-way fridge while towing
Here’s one way to do it without turning on the propane…
Hello Mike….
I enjoy reading your articles. You are very detailed and to the point when addressing questions and always very helpful to the RV community.
Quick question for you….I have a Norcold two-way fridge (electric/propane) that will be on a 6 week and 6,000 trip, and needs to be kept cold during driving hours. I am one that does not like to use propane while driving and am wondering if I could use a portable power station, say 200 or 300 watt, so the fridge stays plugged during driving hours. We will not be boon docking, so nightly plug ins at camps.
Do you see any issues in doing this? The power station would be stationary and protected while riding in the rig.
Your thoughts, please. Many thanks - John
Dear John,
You’re on the right path, but I’m afraid you’ll run out of power in an hour or two with a 300-watt power station like a Jackery 300 Explorer. The problem is that a 2-way refrigerator running on electricity uses around 300 watts for the heating element when not on propane.
Just the numbers…
Let’s assume that your refrigerator heating element will run 50% of the time, and you need to power it for 10 hours while driving. So 300-watts x 10 hours x 50% duty cycle = 1,500 watt-hours. That suggests you would need a power station capable of at least 1500 watt-hrs of storage. So a Jackery 1500 Explorer (in the bottom of the picture) would probably work for this application. Sorry that it costs 5 times more than a 300-watt power Station.
There’s another way…
However if you were to replace your 2-way propane refrigerator with a 12-volt refrigerator that has a Danfoss compressor, it would easily run for 10 hours using the 12-volt DC outlet of a 300 or 500 watt-hr Power Station.
I’ve also tested a Vitrifrigo portable fridge/freezer that would work. Either of these 12-volt solutions could be powered from 100aH Lithium house battery in your RV for at least 24 hours on a single charge.
Let’s play safe out there - Mike
Our first motor home had the propane/electric refrigerator in it. We never experienced any issues with thawing or warm food after a 5 hour drive in the heat of the day, I simple turned it off and made sure the door was secured.
My 2022 Coachmen Spirit had installed a 12v/electric fridge as an option. Due to needing to be level when operating the electric/propane absorption kind of fridge, I thought this would be good to try. So far we love it!!! Tho admittedly I used to drive with my propane turned on to keep the fridge cold, now I keep it off and the battery keeps the fridge nice and cold. This is the first time I've had a 12v fridge. It's 10" cubic in size; well it's actually a wee bit larger than that, and has a feature to put it in conserve mode when we are dry camping. I have 200 watts of solar on the roof and have no issues with the battery running to low. I purchased a 200w solar suitcase from Renogy for when we go dry camping, just in case we are parked in full shade.