Running Gas/Electric Refrigerator on Gas with no AC Power

[Ocnboating]

I have a 2019 331K Cedar Creek with one 12 Volt Battery and no Inverter.

After a overnight with the coach disconnected from my F250 with the refrigerator running on gas the next morning the lights in the coach were very dim.

On another occasion we did a sleep over at a Flying J with the refrigerator on gas and only opening the bedroom slide and the coach connected to our F250 we could not close the slide until we started the F250.

Does a Gas/Electric draw that much amperage or is it possible that I need to have multiple 12 volt battery or possible I have a bad battery.

HELP

Ron

[14apex]

Ron, I'd suspect the battery. The fridge sips only a VERY small bit of power when operating on LP & shouldn't zap the battery for a few days if in good shape...and, if there isn't anything else in the coach actively or passively pulling on it. A battery with lowered (age) capacity will act up the way you're describing.

[SimchaSabre]

Which refrigerator do you have. We have the Norcold 18 CuFt RV and the 12 volt draw is ~ 3amps. The dealer did installed 2 batteries, but I'm thinking they just automatically did that because my 34IK was the first Cedar Creek they'd seen in years without a residential fridge. All that said, I'm surprised that 1 battery didn't do better for you.

I'd check the battery connections and also measure to draw of other power consuming devices like LP monitor, radio, tv amp etc.

[KyDan]

Some refrigerators have a heater in the strip of metal between the fresh food and freezer. Older models had a switch to shut this battery sucking heater off. Current models still have the heater but no switch.
Some of us cut the wire to the heater.
The small amount of condensation that results is better than draining the battery.
It does sound like you may have a weak battery as well.
I wouldn't expect the heater to drain your battery in just 1 night but it is a significant drain fer sure.

[KyDan]

This heater has been discussed in depth here before.

If the fridge manufacturer had made it run on 120v AC it would not be an issue but they made it run on 12v DC so it's on any time the refer is on no matter if you're running it on AC or LP.

This becomes an issue when folks want to boondock off the grid.
If you are interested in disconnecting it- let us know and we'll try to find the old discussion about this process...

The fact that you could not get your slide in after just one night makes me wonder if you were fully charged to begin with? Even tho most trucks do power the trailer thru the hitch plug, they do not normally do a good job of charging the trailer battery due to the long wire run from the engine back to the trailer battery.

It still could be that heater tho.... I disconnected mine shortly after I got my trailer home from the dealer.
It "sweats" a few drops in humid weather but I'm ok with that.

Happy Trails!

[Ocnboating]

Thank you for all your input on this issue.

We have a Dometic RM1350MX Gas/Electric. I know basic electric but I am not sure how I would measure the draw. On the refrigerator label is says it draws 2.5 amps on 12V.

Ron

[KyDan]

Originally Posted by Ocnboating

Thank you for all your input on this issue.

We have a Dometic RM1350MX Gas/Electric. I know basic electric but I am not sure how I would measure the draw. On the refrigerator label is says it draws 2.5 amps on 12V.

Ron

That sounds about right. If you have the standard from the dealer "marine/RV deep cycle/crank" battery, a 2.5 amp drain ALL THE TIME you are off the grid is a lot.
That's why we recommended disconnecting the heater.

[Ocnboating]

Please send me the link on how to disconnect the heater.

Ideally I would like to be able to run the heater on AC power while at a campsite. Possibly this could be done m=by installing a manual switch.

My other thought is tow replace the one 12 volt battery with two 6 volt.

Thanks
Ron

[5picker]

The RM1350 does indeed have a couple of heating elements for condensation/frost.
If I recall, pulling the wire at the Y-connector downstream from J3 on the control module (on the back of the refrigerator) will remove the current from them. Look at the schematic in the manual.

Even so, I can regularly get an overnight on one battery without disconnecting them. (I put a switch on mine)

Have you checked your battery and the charge proccess?
How old is it?

One night on a single battery is very doable and I do it often, IF you start with a fully/properly charged battery.

In fact, while I have two batteries, my selector/disconnect switch I installed allows one battery or the other and I typically only use one at a time so I always have a freshly charged battery to switch to when necessary. When we bought our current unit the dealer gave us a group 24 battery (the smallest capacity) and a couple years later, I can still get an overnight on that little guy.

I'd suspect your battery or the lack of it being fully charged.
Or... you have some other large 12v draw we don't know about.

[KyDan]

Here's a link to the service manual including the schematic.
https://bryantrv.com/docs2/docs/Serv...,%20RM1350.pdf


Your refer is larger and more complicated than mine so I cannot give good advice on specifically how to disconnect and or switch the anti-condensation heater(s).


Hopefully someone smarter than me will take over!

[5picker]

Not claiming to be smarter... but I do have the 1350 refrigerator... and I slept in a Holiday Inn Experess once.

Referring to the schematic...
The power for the heaters come off terminal J3 on the control board. (red wire I believe)

There are two heaters. One in the long flap that closes between the two bottom doors and the other near the partition between the refrigerator and freezer compartments.

You don't want to just disconnect the wire from the terminal on J3 because that ALSO sends 12v current to latch the relay that supplies 12v to the cooling fans.

There is a Y-connector downstream from the J3 terminal where you can unplug the feed wire to the heaters or (as in my case) install a switch.

If you look at the schematic from the link KyDan posted, on page 22 you'll see the two heaters marked K (for the long door flap) and D. (for the the other I mentioned)

A quick way to defeat the long door flap heater is to put electrical tape over the two door contacts on the lower left of the refrigerator door. Marked L in the schematic.

[5picker]

To the OP... while discussing the long flap between the doors...

Be sure to always pull forward (gently) on the flap once you close the left door.

Those flaps have a habit of not fully flipping forward enough to make a good seal on the right door when closed. You'll lose a LOT of refrigerator efficiency if it doesn't make a good seal.

We also never close just the left door with the right door closed. The design of the flapper is to allow that... but it simply doesn't seal well so we pull the right door open slightly, close the left door, pull forward on the flapper and then close the right door.

I gained close to 6º of cooling by making sure the flapper was sealed.

[gbaldwin]

Have about same set up as OP. 1 - 12v. I use Geny to charge battery each evening and anways turn in with a good 90%-100%+ charge per VM and indicator lights. Fridge on Gas....just parasite draws and an occasional light and flush... my battery is normally reading 50% the next morning which is time for recharge.

[tomkatb]

No the fridge does not use a lot!

Modern rv’s have pretty good parasitic loads.

If your rv is new my guess is your dealer installed a small cheap boat battery?

Thus you are underpowered. I suspect you need double per day what you have.

I would also assume you have no fancy, optional battery voltmeter. Thus You are unaware of battery condition.

Maybe the tv is not trickle charging. Maybe the battery is bad?

Maybe you have not used the converter enough to completely charge the little battery! Takes 24 hours or more.

First step for me would be a battery monitor, BM2 , $40 or less on Amazon. So you know what is going on.

I would want 4 Costco six volt batteries.

Batteries are the weak link.

[KyDan]

Well we think that 4 door refer with 2 anti condensation heaters Is a significant load on a single battery.
If Ron is off the grid only occasionally and for just a night or 2, a single 12 volt battery can work. He doesn't need 4 hulking 6 volts for that.
We can go 5 days on just 2 golf cart batteries no problem.

[tomkatb]

One needs to understand their power needs.

Batteries are the weak link. Typically I wonder if new folks understand the battery thing.

Dealers do not help. Selling a rv without a voltmeter seems strange. Mine has an alarm.

A standard installed marine battery has about 500 watts available. That is not much! We have about 2800.

[5picker]

Originally Posted by KyDan

Well we think that 4 door refer with 2 anti condensation heaters Is a significant load on a single battery.
If Ron is off the grid only occasionally and for just a night or 2, a single 12 volt battery can work. He doesn't need 4 hulking 6 volts for that.
We can go 5 days on just 2 golf cart batteries no problem.

Correct. And I stated that in my earlier post.
I do it all the time. With a chincy group 24 no less!

But... there are others that simply say it cannot be done.

[Larry-NC]

Originally Posted by Ocnboating

Thank you for all your input on this issue.

We have a Dometic RM1350MX Gas/Electric. I know basic electric but I am not sure how I would measure the draw. On the refrigerator label is says it draws 2.5 amps on 12V.

Ron

To measured the current craz draw of any appliance, you still need. multimeter with a 10 Amp setting.

Plug the black test lead into Common and the red lead into the 10A jack..

Disconnected one of the appliance power wires--it doesn't matter which one.

Connect the meter in between the power wire and appliance--it doesn't matter which way.

Turn on the appliance and read the current.


If the appliance bas an inline fuse, you can simply unplug the fuse and plug the meter In its place