refridgerator
 

How long should my refrigerator run on 12 volt? Doe's it run off tow vehicle in transit? Is the battery carged by the tow vehicle?

Hi and welcome!

While you are towing, you can run your refrigerator on 12V indefinitely. The only limitation would be your tow vehicle's alternator output, and possibly the wiring from the alternator back to your trailer plug. Some tow vehicles can't keep up with the demand of a refrigerator and the refrigerator will then draw current out of the trailer's battery to make up the difference. If this happens, you could arrive at your campground with a depleted trailer battery.

If the battery is too low, you won't be able to raise the top of your trailer to the camping position. You'd have to run jumper cables from the tow vehicle to the trailer battery to get it up, or, raise the top manually.

And yes, as long as the fuse is in the tow vehicle's charging circuit and if the refrigerator is not pulling too much power, the tow vehicle charges the trailer battery while in transit.

- Jack

Thank you Jack for the information. I know you are not suppost to run it on gas while traveling. Can I run it on gas with the top loweredwhen I stop?

No! That is actually why you should not run it on gas while traveling.

I'll say it a different way though: You should not power the refrigerator on gas if the trailer is not moving with the top down. There is insufficient air circulation to properly vent the gas system in this situation.

And, you should not have the refrigerator, hot water heater, or furnace powered on with gas while you are refueling the tow vehicle due to the possibility that the open flames will ignite fuel vapors causing an explosion.

But, some people have operated the refrigerator on gas with the top down while the trailer was moving. Personally, I would not do it.

- Jack

Jack,Thanks again. I have a V10 Excursion so I shouldn't have a problem charging. My HI-LO has two new batteries. If I stop on the way how long will 12v run the fridge?

I've stopped for close to an hour, leaving the refrigerator on battery power, and, like you, I have two batteries in the trailer. But I think it depends a lot on the outside temperature.

I still have plenty of power to raise the top when I get to the camping area when I do this, but I've also put the generator I carry on to the trailer's shore power cord as soon as possible to "top the batteries off".

Don't raise the top with the tow vehicle connected! If the refrigerator is pulling power when you do it, the total load can blow your tow vehicle's 30 Amp charging fuse. It's happened to me more than once until I figured out what was happening.

- Jack

You can go a long ways without the fridge turned on if you have it cooled ahead of time and have it filled with cold food. You can add a couple jugs of frozen water to help keep it cold.

I had problems with running my fridge on 12v even while driving. I would arrive, the temp in the fridge would be acceptable, and the battery would not be able to lift the top.
It was being charged while driving but wasn't strong enough to overcome the use.

I NO longer use the 12v fridge setting. I only use the 120v , and gas. I installed an inverter(1200w) in my trlr that powers the fridge while driving and short stops.
The inverter showed me that the fridge on 120v only uses 200 watts and easily keeps up with use.
I do have to plug the fridge into the 120v plug on the inverter when driving instead of the trlr plug-in. small inconvenience.

Fridge stays at same temp regardless of driving distance and time.

I believe that the 12v element needs to be over powered for the amount of performance that is needed. Thus shortening the battery performance

This may not sound like it would work. But I used it this year on our 3.5 month trip and it worked flawlessly.

I never thought of using an inverter. I am intrigued. With two group 27 batteriess running off a 130 amp alternator on my Nissan Titan- I've driven maybe six hours going home with fridg on 12v. I can raise the top when I;m done, but a multi meter shows that the battery is below being topped off when I get there- and other similar runs without the fridge I'm "full" when I get home. I realize this is dependent on the state of charge when I begin the return trip------but all things being equal- I can't keep up with a running 12v fridge. This IS NOT what I want if I'm driving all day and boon-docking that night-

Rick

Strange 200 watts at 120 volts equals 16.66 amps at 12 volts not including the loss from the inverter since it isn't 100% efficient. My refrigerator pulls 8 amps at 12 volts. I can't explain why your battery would go low using the 12 volt element, but not the 120 volt element when you are using at least twice the amps. However, if it worked for you that's great :) I wonder if the 120 volt element is more than twice as efficient as the 12 volt element. Something to check as I have a 400 watt inverter laying around doing nothing :)

Different models and sizes of fridges could dictate the power requirements. Our 2310H fridge draws 15 amps on 12 volts.

Correct! And that's just 180 Watts! It's very little POWER, really but when the voltage (electrical pressure) is low, the Amperage (electrical volume) has to go up and that high Amperage needs a fat wire (big pipe) or it can't get though. (I know you know this Rich, I'm just trying to explain things to some that may not.)

Now, if the voltage was 120, the needed Amperage would be 1.5A. You can pass 1.5A through a very small wire.

So, this is why the inverter may be a good solution, if the battery charging circuit from the tow vehicle to the trailer is designed with wire that isn't a heavy enough gauge.

And, 180 Watts may be a low power requirement, but 15A is a heavy draw on a battery! In four hours, that pull totals 60A, which kills most wet cell batteries. However, if you can supply the power from the tow vehicle's alternator, either through the charging circuit or through an inverter that's powered from the tow vehicle, you can run the refrigerator indefinitely, as long as the engine is running. But, if you adopt the inverter solution, you need to get its input from the tow vehicle, not the trailer, or you will be increasing the draw on the trailer's battery.

- Jack

Refrig
 

I caution worth consideration (because it happened to me). I do run my refrigerator on 12 volts when towing. My truck's alternator is powerful enough (if that's the proper term) to keep the Hi Lo batteries charged and run the refrigerator as I tow. I would caution to cut the refrigerator off (of 12 volts) if you stop for longer than to fill up with gas. I didn't once when we stopped for lunch for about an hour. Got back in the truck and headed on. Found that when I got to my destination that the Hi Lo batteries had been run down powering the refrigerator while I was stopped for lunch. So now if I stop for a longer period that it takes to refuel I will cut the refrigerator off and turn it back on when I'm ready to go. It is already cold in the refrigerator so cutting it off for an hour or so it alright. If you don't think that would work for you, you could always raise it and run it on gas while stopped. But for short periods it will work fine being cut off.
God Bless
Papa