Dometic 3-way... pro's and con's of driving with propane on

[AG_Ltd]

Thanks very much for your input Booster, it's much appreciated, however, please reply to the compressor fridge topic over on the Sprinter-Source forum to keep it separate from this post which is asking about driving with propane on. Thanks!

[hbn7hj]

Originally Posted by AG_Ltd

With new batteries, I'll now see if my fridge stays on LP, and test it at elevation. It will be later this year but I will post my results.
https://sprinter-source.com/forums/i.../#post-1129863

I run a Dometic 3-way from 9300ft to almost 11,000ft all summer. I can hear it struggle to light sometimes but it usually does. I keep an eye on it and the temperature reporting system has an alarm. It fails to light about once every two weeks or so. Off, then on and it continues. I have a compressor in the wings but I just don’t want to mess with the power. Starlink is gonna take enough.

I’m due for a burner cleaning and will get into it when it fails more often.

[AG_Ltd]

Originally Posted by hbn7hj

I run a Dometic 3-way from 9300ft to almost 11,000ft all summer. I can hear it struggle to light sometimes but it usually does. I keep an eye on it and the temperature reporting system has an alarm. It fails to light about once every two weeks or so. Off, then on and it continues. I have a compressor in the wings but I just don’t want to mess with the power. Starlink is gonna take enough.

I’m due for a burner cleaning and will get into it when it fails more often.

Thanks for writing... I was hoping to hear from other owners of Dometic 3-ways. (What is your model?)

Now I know it's possible to run it at high elevations. A friend suggested that Dometic says to find shore power "above 5500" in the manual just to cover their arses, but that they do work (like yours does). In any case I'm hopeful now. Thanks again!

[hbn7hj]

Originally Posted by AG_Ltd

Thanks for writing... I was hoping to hear from other owners of Dometic 3-ways. (What is your model?)

Now I know it's possible to run it at high elevations. A friend suggested that Dometic says to find shore power "above 5500" in the manual just to cover their arses, but that they do work (like yours does). In any case I'm hopeful now. Thanks again!

RM 2354 and RM 2663. Both have fans in the back, both have ARP devices and a light on the dash to tell me if they turn off. They also have a relay to turn off the DC heater element when the ignition is off and an RF temperature monitoring system.

[peteco]

My Dometic 3-way propane operation was very sensitive to propane pressure. It would occasionally cut off and the check light would come on. I checked the propane pressure and it was about 10.5 inches, which I thought should be high enough but it was not. I replaced the propane regulator and so far the fridge has not cut off after a year of use. I didn’t measure the pressure but it is supposed to be 11 inches. I suggest getting the propane pressure checked at the refrigerator.

[Want a B]

Remember. No open flames when refueling vehicle. Turn off LP before parking at the gas pump and turn on again after leaving.

[AG_Ltd]

Originally Posted by peteco

My Dometic 3-way propane operation was very sensitive to propane pressure. It would occasionally cut off and the check light would come on. I checked the propane pressure and it was about 10.5 inches, which I thought should be high enough but it was not. I replaced the propane regulator and so far the fridge has not cut off after a year of use. I didn’t measure the pressure but it is supposed to be 11 inches. I suggest getting the propane pressure checked at the refrigerator.

PeteCo:
Do Dometic 3-way models 8501 come with a built-in pressure regulator and can my repair shop order a new pressure regulator for this fridge? Thank you!

[AG_Ltd]

Originally Posted by hbn7hj

RM 2354 and RM 2663. Both have fans in the back, both have ARP devices and a light on the dash to tell me if they turn off. They also have a relay to turn off the DC heater element when the ignition is off and an RF temperature monitoring system.

hbn7hj
Please remember, I'm not at ALL technical and have no idea what ARP device is or if my model has a "DC heater element" or what an RF temperature monitoring system is. Not understanding these things is part of the problem I know, but I find that most RV repair techs don't know either. If you explain further, I'd appreciate it but if not, thanks for the information!

[rvsprinterguy]

Before we go camping, I pre-cool our Norcold 3-way refrigerator on AC. When we're about to leave, I switch to Propane and we drive away. My experience has been that the fridge won't stay cold in hot weather on DC. During trips in the summer, driving up or down I5 in the Central Valley, when on DC, the temperature rises steadily; when on Propane the fridge can keep up. When getting Diesel, I always put out the Propane flame, close the tank valve and switch to DC. After leaving the gas station, I re-light the fridge.

Another time I douse the Propane flame and close the tank valve is when I plan to go through a tunnel such as the Tom Lantos tunnel on Highway 1 south of Pacifica, because that's the law.

Otherwise, I can't imagine a safety reason to not run the refrigerator on Propane.

[Tom_T]

Originally Posted by AG_Ltd

I have a Dometic 3-way fridge (Model 8501) which has the options of running off LP, my 12v batteries or shore power.

When I plan to drive for a few hours, I leave the propane on (OH NO!) because I've been told if I switch it to DC, the draw from the fridge will not allow my 12v batteries to charge while driving. (Since I can't drive while plugged in, the only other option is turning the fridge OFF altogether and hope everything stays cold enough not to spoil.)

I've heard horror stories about explosions however I don't want to drain my batteries nor do I want spoiled food.

If you say it is really dangerous to drive with propane on, then please also provide a solution to my dilemma.

Thank you

P.S. I have a 2013 Roadtrek SS Agile, my battery system is two 224-amp hour Fullriver batteries in series. Not sure about the alternator.

I've never heard that batteries won't charge at all when running the fridge on DC, nor have I experienced that ever with our 1988 Westfalia over the past 34 years, but it may recharge more slowly - which is only a concern if your battery(ies) are significantly discharged.

However, the DC doesn't keep it as cold - e.g.: I can make ice in the teeny-tiny ice cube trays with LP/110V, but only get a skin of ice or keep them frozen barely on 12V (it's the original 1988 Dometic, so yours may be better & newer technology).

Most often I run the fridge on LP until at the campsite, then switch to 110/115/120 V shore power to conserve LP (Westies have small LP tanks).

There are some tunnels where you're supposed to turn off & close your LP tanks, so be aware of that - but otherwise I say run on LP.

PS - Yes, also pre-cool over night/day on AC, then load your fridge - as noted above. That's basically the same pre-cooling that you'd do with your home fridge before adding food.

Safe Travels!
Tom
///////

[peteco]

Originally Posted by AG_Ltd

PeteCo:
Do Dometic 3-way models 8501 come with a built-in pressure regulator and can my repair shop order a new pressure regulator for this fridge? Thank you!

No fridges have a built-in regulator. If you can find a Dometic authorized service facility, or refrigerator knowledgeable facility,they can check the pressure at the refrigerator. If the regulator is bad they should be able to figure out where it is and change it. Then they should check the pressure again to make sure the new regulator is good.

[hbn7hj]

Propane regulators have a simple adjustment to get the proper pressure of 11” of water. Clockwise to increase, I think.

The adjustment is not accessible on Roadtrek Chevy 190 and 210s but I expect it is on most other Bs.

Just remove the plastic cap and adjust it. Some use an allan wrench, some use a screwdriver.

[sehsteve@gmail.com]

Originally Posted by AG_Ltd

I have a Dometic 3-way fridge (Model 8501) which has the options of running off LP, my 12v batteries or shore power.

When I plan to drive for a few hours, I leave the propane on (OH NO!) because I've been told if I switch it to DC, the draw from the fridge will not allow my 12v batteries to charge while driving. (Since I can't drive while plugged in, the only other option is turning the fridge OFF altogether and hope everything stays cold enough not to spoil.)

I've heard horror stories about explosions however I don't want to drain my batteries nor do I want spoiled food.

If you say it is really dangerous to drive with propane on, then please also provide a solution to my dilemma.

Thank you

P.S. I have a 2013 Roadtrek SS Agile, my battery system is two 224-amp hour Fullriver batteries in series. Not sure about the alternator.

A very interesting thread to me. I have a 2002 Roadtrek P 190 that I have put about 31,000 miles on since purchasing it in April, 2019. Prior to my purchase I had no interest in RV's which also means no knowledge. I think it is the original refrigerator. Somewhere along my learning curve I was told it is good to travel with propane on and that is what I have done for short or coast to coast trips. I have not actually used the DC power, only shore power went available. Shore power seems by far the best for cooling. Maybe I need to change my ways to DC when traveling, IDK. I'd appreciate more info on this subject too.

[booster]

Originally Posted by sehsteve@gmail.com

A very interesting thread to me. I have a 2002 Roadtrek P 190 that I have put about 31,000 miles on since purchasing it in April, 2019. Prior to my purchase I had no interest in RV's which also means no knowledge. I think it is the original refrigerator. Somewhere along my learning curve I was told it is good to travel with propane on and that is what I have done for short or coast to coast trips. I have not actually used the DC power, only shore power went available. Shore power seems by far the best for cooling. Maybe I need to change my ways to DC when traveling, IDK. I'd appreciate more info on this subject too.

The big question is if you remember to turn it off every time you get fuel? I think there is also a fuzzy area about, what if you stop at a gas station/minimart for your morning coffee and drive by/park near the pumps? I have never heard an answer to that. eg how close it too close to a possible source of combustible gas.

[ChicagoTom]

Originally Posted by NAZCamperVan

I'd rather save propane for use when camping, and use 12V power for the fridge when on the road.

LOL, I full timed and using the fridge 24/7, hot water and furnace at night it cost about a buck a day

[ChicagoTom]

I disconnected the useless 12V. Way too many horror stories about forgetting to shut it off. If you don't want to run the propane while driving, run it while taking breaks, lunch, rest etc. The propane on for 30 minutes will equal the 12V on while driving for a good 3-4 hours. All just my opinion, ex HVAC tech many years ago

[AG_Ltd]

Pls clarify: Is the pressure regulator a "part" of the propane "system" which supplies the furnace, stove, fridge etc? Thank you

[AG_Ltd]

I have a Roadtrek Agile so am not sure where the propane regulator is... do you happen to know by chance? Thank you.

[AG_Ltd]

I have to admit, sometimes I don't turn my propane off until I'm next to the pump. MY BAD. I've been lucky so far!!! I MUST remember to pull over BEFORE I enter the service station. Thanks for the reminder!

[AG_Ltd]

Originally Posted by booster

The big question is if you remember to turn it off every time you get fuel? I think there is also a fuzzy area about, what if you stop at a gas station/minimart for your morning coffee and drive by/park near the pumps? I have never heard an answer to that. eg how close it too close to a possible source of combustible gas.

Great question! Does anyone know the answer?