Running a 3-Way Dometic Refrigerator on DC While Driving

[Mardeldelmar]

Will the fridge keep cooling while driving if it is on DC and I suppose the on board battery switched to ON? Thx

 

[Johnnyfry]

The fridge will operate on DC while driving, but the cooling capability will be seriously reduced over propane operation. At best you might maintain temperature in moderate temperature conditions... 60º or 70º, but in my experience anything higher, the fridge will temperature will gradually rise. I am not interested in a discussion about Propane safety, but I have operated my fridge on Propane while driving for many years without problems. Needless to say, I turn the fridge off before entering a filling station.

 

[peteco]

Will the fridge keep cooling while driving if it is on DC and I suppose the on board battery switched to ON? Thx

What make and model of Class B do you have? I ask because some, like my 2006 Roadtrek 210P, did not have the fridge installed properly by Roadtrek according to Dometic directions. Because of this the fridge cooling was not optimal during any operation, from hooked up to 120v, gas operation, or DC. In addition fridge performance can vary from fridge to fridge based on how optimum the cooling fluid amount was. I have done extensive upgrade of my RM2554 Dometic fridge install, which has resulted in the fridge cooling pretty well for a gas absorption unit. This includes 12v DC operation while driving. Mine will maintain temp level while driving in hot weather and even lower the fridge temp in cooler outside temperatures.

Here is a description of the modifications:

Roadtrek 210P Refrigerator Problem Solutions

The Dometic RM2554 refrigerator in my 2006 Roadtrek 210P had poor performance in hot weather with fridge temperatures into the mid 40’s in hot weather. The fridge was slow to recover after opening the door more than just a few seconds. The freezer was good at near 0-degrees. Note that some of...

www.classbforum.com

 

[Mardeldelmar]

The fridge will operate on DC while driving, but the cooling capability will be seriously reduced over propane operation. At best you might maintain temperature in moderate temperature conditions... 60º or 70º, but in my experience anything higher, the fridge will temperature will gradually rise. I am not interested in a discussion about Propane safety, but I have operated my fridge on Propane while driving for many years without problems. Needless to say, I turn the fridge off before entering a filling station.

Thanks, I appreciate the input and will travel accordingly

 

[GallenH]

Agree with others. On a 3-way the 12v option is the least effective. I believe this is due in part to the heat output of the 12v heating element vs the 120v heating element. Being in AZ I've made some trips in pretty hot weather and generally find the 12v to do a reasonable job of keeping things cool. But my 120v element does a pretty good job of rivaling the LP. I've often wondered whether it would be a solution to have a small inverter that you use only for the fridge and only when you're driving.

 

[Roadtreker357]

Our 07C210 has the original refrigerator and is run on DC while driving. It has maintained the temperature that was there before switching to DC. I have not yet looked at the modifications Petco has made but suspect mine are similar; installed a Reflectix baffle to keep the hot air from the exterior wall from getting to the condenser and have a homemade Snyder kit installed with an intake hose attached to the fan (dryer vent) to draw air into the fan from the lower vent.

I have a wireless temperature setup, both freezer and main compartment, so moniitoring temp is easy. I suggest you get the frig cold with LP gas or A/C and then just try running on DC at the start of a trip to see what happens in your situation.

 

[TX-Trek]

Our Dometic seems to work fine on 12v while driving. The only modifications, other than keeping things clean in the back are three 12v fans on a manual switch. They are located on the upper grille area of the unit. They draw air from the lower vent area out through the top vent and there's definitely heat generated in there. You can feel it in the airflow out.

 

[Tom 98072]

Will the fridge keep cooling while driving if it is on DC and I suppose the on board battery switched to ON? Thx

My dometic 3-way frig actually cools to a lower temperature on dc at the same setting while traveling than when we’re on shore power and using ac. The main concern is where is the sun? The sun has a huge impact on the cooling ability; for us it seems to matter more than temperature but we’re seldom in temps above 80.
Also, safety and restrictions are items to consider. Too much can happen, accidents are not the only problem. Also, many ferries, tunnels, toll roads require the tank valve be closed and tagged. And there are some situations where you can’t go anyway because they allow NO propane

 

[ChicagoTom]

The fridge will operate on DC while driving, but the cooling capability will be seriously reduced over propane operation. At best you might maintain temperature in moderate temperature conditions... 60º or 70º, but in my experience anything higher, the fridge will temperature will gradually rise. I am not interested in a discussion about Propane safety, but I have operated my fridge on Propane while driving for many years without problems. Needless to say, I turn the fridge off before entering a filling station.

I do the exact same thing. I was a refrigeration tech many years ago, and IMO the 12V operation is useless. Many horror stories, at least from PleeasureWay users, of forgetting to shut it off, and that in turn killed their house battery. The first thing I did when I installed my new RM2354, was to disconnect the 12V option.
Same here Johnyfry, not going to debate the propane while driving safety, my propane keeps the fridge ice cold up until around 100 degrees, then it'll keep it cool, but be careful what you are storing in there.

The fridge will operate on DC while driving, but the cooling capability will be seriously reduced over propane operation. At best you might maintain temperature in moderate temperature conditions... 60º or 70º, but in my experience anything higher, the fridge will temperature will gradually rise. I am not interested in a discussion about Propane safety, but I have operated my fridge on Propane while driving for many years without problems. Needless to say, I turn the fridge off before entering a filling station.

 

[peteco]

I use the 12v operation when going through the tunnels in Hampton Roads VA that ban propane operation. Baltimore tunnel bans propane operation as well.

Sometimes I use propane while traveling and sometimes 12v. It is unfortunate that 12v works poorly for some and well for others.

 

[RT-NY]

I always use the 12v when driving, and it works great for me -- it doesn't cool as well as the 120v because the heating element is lower wattage, but it's fine. The issue with forgetting to turn it off and draining the house battery is a real concern, but you can just set up something as a reminder.

 

[Doneworking]

Peteco is on target when he says it works ok for some and doesn't work sufficiently for others.

We have the 5 cf three way in our 2007 RT 210 and we normally are doing trips of a week or more. We keep the refrig really full and use only a little Camco fan that runs on two D cells inside to circulate the air. We put a couple of blue ices and a few cold Cokes in it when we fire it up on 120 or gas. We do this a couple of days before we are leaving and we pack it full the day before we leave. We have no trouble keeping the refrig in the mid 30s and the freezer compartment just a few degrees above zero when on AC or gas.

When we are going down the road, we run it on 12v just to maintain the temps and not hassle with turning off the propane when we refuel. Normally on a hot day the temp in the refrigerator will rise to the low 40s after seven or eight hours. That is about as many hours as we are going to drive in a day and then we switch back to gas. I define hot as mid 90s to a hundred.

We have never had any issues doing this and we bought our RT new in 2006 and still have it. I keep the door seals in good shape and the entire thing is stock just as it was when we picked it up new. I do check the refrig over carefully each spring being mindful of the gas jet, flu, etc.

SO, we are just lucky to be on the side of those that have had no problems. Camping, of course, we always use gas even if we have a plug in and only use the 12v for going down the road.

These Bs almost need a check list like you are flying a plane and I suggest newbies make one up. We have had Cs and gone down the road without incident on gas, just remembering to turn it off before refueling.

 

[Mardeldelmar]

Hi, and thanks for all the info. Getting ready for a trip and find that the fridge is ONLY working on gas. Not DC or AC. Has worked on AC before…any helpful tips? TX

 

[DaveBad]

This is a long video but it covers a lot of possible issues.

 

[Grumpy2]

If you determine the control board is the problem, I had good luck with a replacement for our Chinook years ago from Dinosaur Electronics.

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