Community Forums

Torchic · 02-04-2023, 05:20 PM

So im trying to weight my options here. Long story short I'm trying to find a way for my fridge to still be on while traveling without using propane. So far I have 2 "work arounds" 1st) give it a dedicated inverter and just unplug from rv outlet while traveling. 2nd) is use one of those electric battery "generators" and plug Into that while driving. Only thing I'm concerned with this option is how long the generator would last. My fridge says it takes 300watts. So my question is is that 300 watts every hour, 24hrs a day? Or just 300 watts per hour it's on, but it only runs X amount of min per hour. If anyone could let me know so I can get a better understanding and try to get something figured out ide greatly appreciate it.

Ray,IN · 02-04-2023, 05:39 PM

The fridge only consumes power when the thermostat calls for cooling. That depends upon several factors. are the door seals intact and holding tightly, the dollar-bill test determines that. Close a door on a bill, if you can easily pull it out anywhere around the door the seal is faulty.
Next is items in the fridge, if everything inside is cooled down to fridge thermostat setting the fridge should stay cold for about 6-8 hrs without any power; BUT if a door is opened that is no longer true.
Each time a door is opened cold air spills out, to be replaced with warm humid air in the RV.

The vast majority of we RVers run the LP cooling unit while traveling, the fridge is certified by the mfgr as safe for use while in motion, as are all other LP appliances in an RV.
I find it interesting some are fearful of running an LP fridge, water heater or furnace while traveling, yet think nothing of the 30-40 gallons of gasoline towards the rear of the vehicle in which they are riding.

TandW · 02-04-2023, 05:46 PM

You can run your reefer on a separate, dedicated 500 watt inverter. I have that setup in the old Allegro 31IA.
Rated at 300 watts on the AC side, and having a nominal duty cycle of 50% your reefer will use 3.6 Kilowatt-hours of electricity daily.
Be sure to use adequately sized wiring and fuse to protect the inverter circuit.
#10 wire and 30 amp.

Jay D. · 02-04-2023, 09:00 PM

I run mine on propane for the time i leave home until i get back, this can be a month sometimes. save yourself a bunch of money and inconvenience and just run it on propane. every one does.
Jay D.

JMitchell · 02-04-2023, 09:25 PM

If you absolutely don't want to run on Propane while moving, we just use the old icebox trick of freezing a handful of 16oz water bottles and putting them in the fridge and freezer.

We have done that for ferry and tunnel trips.

Normally however we just run on Propane while moving.

Main reason I don't make a difference between running an absorption refrigerator on Propane or AC, is that you are just swapping the heat source from flame to electric heat source..

Except for the explosion risk in a confined space and the CO and CO2 from the propane, not much different.

Mudfrog · 02-04-2023, 09:39 PM

The frig does not use much propane. It's ok to run it on propane while driving, most of the time. Some tunnels require a frig to be off going through them and it's usually a good idea to turn it off at gas station fill ups. Otherwise, firing with propane is fine.

A smallish inverter would work but you would need to get heavy enough wiring installed between it and the coach battery to run it.

Or, you can simply leave the frig off if your food is already cold and you're only going to be on the road for a few hours. It's insulated and will hold its cool fairly well if you don't open/close the door too much. Ice cream might get a little soft but that's the way I like it!

twinboat · 02-05-2023, 03:34 AM

300 watts is 23 amps at 12.6 volts.

I'd suggest that the fridge is going to run 75% of the time. Absorbsion fridges are not very effecent.

6 hour drive, fridge running 75% of the time, 100 AH from a battery bank.

I may plug mine into my Kill A Watt meter, later to test.

Marine359 · 02-05-2023, 08:18 AM

Icebox solution works best for what you’re trying to accomplish. Just put in three frozen plastic ice bags, the kind you get when you order meat on the internet. Having a fan in the fridge will help the bags last longer. Don’t open the fridge door. When you get to shore power, Re freeze the bags. Although we have a compressor fridge, the issue is the same when we boondock. The fridge uses more of our battery capacity than we want, so the ice bags work at reducing compressor run time. Or, we can actually turn off the fridge and it will stay cold all day.

bobphoenix · 02-06-2023, 04:55 PM

My TT came with a 110V fridge that was pretty old when I got it, so I decided to replace that original with a new Magic Chef, 4.7 CF unit.

Before I installed it in the TT I did a static test in the driveway.

I connected a 700 watt power inverter to the battery in my car (625 CCA) without the car running, and plugged in my fridge with an LED lamp (to show when and if the battery power ran out...) I set the fridge thermostat to 6 (out of 1 -9), put thermometer in the freezer and at noon, I turned it on...

I did everything I needed to, around the house for the rest of the day. And, by 10 PM I finally remembered that I did the set up! (I would never travel for ten hours on a journey).

To my surprise, the freezer thermometer was reading 5 degrees, the lamp was still lit and I got in the car, turned the key and the car started like there had been no load on the battery.

So, that's my recommendation... Tap your inverter into the battery and run your fridge on it while you traveling... then plug the fridge back in when you're on shore power... (Or buy a cheap transfer switch for an automatic changeover).