Dometic 3-way fridge not cooling on gas

[The Minimalist]

Originally Posted by greenghost45

You should use compressed air, preferably high pressure of 100 psi.

Caution: with 100 psi air, you're likely going to be searching for that orifice in the next county.


Plain old denatured alcohol from the local hardware or big box home improvement center will clean the orifice. You need to remove it to soak it.



By the way when you consider the size of the orifice, even the smallest obstruction, will reduce it's area dramatically. You may not see particles, but there may be coatings that build up from the gas and or odorant which might not be obvious, even under magnification.



Also, spiders have an affinity for the odorant in LPG so cobwebs in the burner unit are common.

[Doctor Harold]

Everclear will work as a cleaning solvent as well and is available at many liquor stores:

[MBrad]

Originally Posted by CalgaryEscape

Hi: I have a small Dometic fridge - model RM 4223. It cools well on 120 and 12V, but barely cools on gas. Tried cleaning the gas tip with a pipe cleaner and alcohol, but that didn't really do the trick. Flame doesn't get bigger. Any suggestions? Should I suspect the Thermister? Anything else? (BTW, took it into a local shop, and the RV repairman declared it dead and claimed it wouldn't cool at all . . . basically, either a liar or incompetent. Figured I'd do better tackling it myself.) Open to any and all suggestions.

If the fridge works on 120V and 12V, your gas is the issue. The fridge is a gas absorption system so if it cools on one energy source, then the refrigeration system is fine. The other people on the post already pointed you in the right direction; the LP gas system is not providing enough heat to cause the vaporization of the gas in the refrigeration system.

[ZachO]

I agree about 90% with this. Having been through quite an ordeal with my own fridge, I will say that what you wrote is generally true, BUT...

The propane creates quite a bit more heat than 12/120V. If that heat isn't doing its chimney thing effectively, and instead getting stuck in the fridge compartment, that'll affect cooling. My fridge doesn't work perfectly on any power source, but it works worst on propane. In my case, there may be some issues with the coils themselves, but mostly it's a problem of the installation of the fridge and the construction of the fridge compartment. They built it in a way that works really well, if the purpose was to trap heat in the fridge compartment and work against the chimney effect that the fridge needs in order to cool.

So there could be an issue with the compartment, which only shows itself when using the highest-heat method of...cooling.

[Lloyd (aka Santa) Coltman]

Yup, a slightly low propane supply pressure will make a perfectly good good fridge look like a boat anchor. If it works on shore power, it's good, so get that regulator checked as first step. Regulators do go off calibration, and it's critical! Then, you might investigate making a couple of mods to eliminate airflow 'Bypass' of cooling coils, for increased efficiency.

[Osos1]

My five year old Dometic would not cool on propane. It would light, yet after unplugging from AC the temp would go up to over 52 degrees very quick after being at 42. Removed and cleaned the burner; blew out the chimney with air, and still no luck. Finally removed the orifice and looked up at the sky and saw a small particle. Sure enough, after soaking in alcohol for 10-15 minutes the fridge cooled better than it ever has.

[greenghost45]

Originally Posted by The Minimalist

Caution: with 100 psi air, you're likely going to be searching for that orifice in the next county.


Plain old denatured alcohol from the local hardware or big box home improvement center will clean the orifice. You need to remove it to soak it.



By the way when you consider the size of the orifice, even the smallest obstruction, will reduce it's area dramatically. You may not see particles, but there may be coatings that build up from the gas and or odorant which might not be obvious, even under magnification.




Also, spiders have an affinity for the odorant in LPG so cobwebs in the burner unit are common.

Well, that's how I cleaned mine and many other parts over the years. Clearly, you must grip the part and the air gun doesn't have to be at point blank range. The alcohol alone may work, but the compressed air is a sure thing. A close friend is a licenced gas fitter with 30 years of experience, and that is what he does.

[ZachO]

I'll tell you from experience, unless you're lucky enough to buy a camper with a fridge install that just "works", and don't have an older camper, making these things work well can be a full time job.

I had a plan to make really good progress on a grant application yesterday. I did make good progress for about two hours. I then I went to turn my fridge thermostat down a bit, and the knob gave me some resistance...then just spun freely. 5 hours later and everything was back to normal again, after pulling the fridge, finding the problem, getting parts, fixing it, installing the fridge again. What fun. My fridge takes up more time by far with trouble shooting and maintenance than probably everything else in my camper, combined.

[greenghost45]

Originally Posted by ZachO

I'll tell you from experience, unless you're lucky enough to buy a camper with a fridge install that just "works", and don't have an older camper, making these things work well can be a full time job.

I had a plan to make really good progress on a grant application yesterday. I did make good progress for about two hours. I then I went to turn my fridge thermostat down a bit, and the knob gave me some resistance...then just spun freely. 5 hours later and everything was back to normal again, after pulling the fridge, finding the problem, getting parts, fixing it, installing the fridge again. What fun. My fridge takes up more time by far with trouble shooting and maintenance than probably everything else in my camper, combined.

The fridge in my 1973 Boler did NOT work on propane and it is the original fridge. After carefully cleaning the gas orifice, I got it to work great. But if it gives up the ghost, I will be replacing it with a compressor type 12 volt like a Nova Kool or similar. Had a Waeco compressor 12 volt fridge on my sail boat and loved it. Kept the beer cold in Mexico for years with no issues.

[ZachO]

My fridge troubles have quieted down a bit over the last year or so, and so I think about it less. But yes, 12v compressor is a very serious consideration for me too, when this fridge stops being worth the maintenance.

100% professional fix. "No one has ever fixed a fridge better than this". DL.











Spraying a little white lithium grease onto the actual thermostat mechanism this rod turns is what saved me. The dial turns smoother than ever.

[greenghost45]

We had a Waeco CF-35 compressor portable like this one in our sailboat while we cruised Mexico for 2 years, and on the BC coast for about 8 more years. It never missed a beat and the current draw was manageable with 2 solar panels totaling 150 watts. Kept the Coronas cold when it was still a good thing to have corona aboard while cruising :-). I also used it for truck camping trips. The Dometic branded one is this link is the same as a Waeco; just renamed. You can also run these as a freezer but they will draw a lot more power. Wonderful units! But don't confuse this with a 12 volt Koolatron or similar. They are power hogs and hardly cool at all.

https://www.dometic.com/en-ca/ca/pro...cf-35-_-140221

[ZachO]

That would take getting used to, being a cooler setup rather than a household fridge setup, but still worth looking at. I like that my fridge is upright and has shelves (and a freezer). But I know there are other options in the 12v world.

Yeah...corona on board a ship is definitely not something to wish for these days...

[greenghost45]

Originally Posted by ZachO

That would take getting used to, being a cooler setup rather than a household fridge setup, but still worth looking at. I like that my fridge is upright and has shelves (and a freezer). But I know there are other options in the 12v world.

Yeah...corona on board a ship is definitely not something to wish for these days...

Being top loading, the chest fridges make better use of space and are more efficient to boot; every time you open a regular fridge door, all the cold air spills out. But they do take up floor space, which is at a premium in a Boler. If we get another one, we'll probably keep it in the back of the tow vehicle. The Nova Kool fridges can be put in the old fridge cut out.

Nova Kool, refrigerators, freezers, Marine, RV, Truck

[Iowa Dave]

Originally Posted by Doctor Harold

Everclear will work as a cleaning solvent as well and is available at many liquor stores:

You would only need a capful. What do you recommend a person do with the remainder of the bottle?
Iowa Dave

[greenghost45]

Originally Posted by Iowa Dave

You would only need a capful. What do you recommend a person do with the remainder of the bottle?
Iowa Dave

In Hyder, AK, the local bar will pour you a shot of Everclear (they don't tell you what it is) and you are expected to down it in one gulp. No sipping, sniffing or tasting, just SKOLL! If you don't pass out or throw up, the shot is free and you are "Hyderized" with a card to prove it. BUT, if you fail, you buy a round for the house. I was successful, but just barely! My then girlfriend was even closer to losing consciousness, but managed to hold it together. I think there was only a couple of other patrons, so failure would not have been ruinous. That was in 1985 and I have not had Everclear since!

How to get hyderized – Riding Full Circle

[ZachO]

Originally Posted by greenghost45

Being top loading, the chest fridges make better use of space and are more efficient to boot; every time you open a regular fridge door, all the cold air spills out. But they do take up floor space, which is at a premium in a Boler. If we get another one, we'll probably keep it in the back of the tow vehicle. The Nova Kool fridges can be put in the old fridge cut out.

Oh yeah, everything about them makes sense, except that they don't feel like a fridge, they feel like a cooler. Most of us could get over it. It's just nice to have a fridge like a household fridge when you're in a camper. Otherwise might as well be car camping with a cooler.

I've seen people post photos of one of those type fridges mounted as a slide-out in the old fridge compartment, which at least saves the floor space. Still feels like a cooler, but it's an improvement.

[Civilguy]

Originally Posted by Nicolas

search out a good local person for each job you do. And I agree with the fact that this is a tough thing to do but ask around in your area.

Does anyone remember Tom Hanks appearing as "Doug" on an episode of Black Jeopardy on Saturday Night Live ?

The host Darnell Hayes asks Doug whether he’s sure he wants to play; Doug says he’s just hoping to win some money, so “get ’er done.”

The question of what to do when the mechanic says you owe $250 for new brake lines leads Doug to answer “You better go to that dude in my neighborhood who’ll fix anything for 40 dollars”.

Hayes excitedly asks “You know Cecil?!”

Doug says “Yeah, but my Cecil’s name is Jimmy. He fixed my air conditioner, my refrigerator, and my cat.”

[CalgaryEscape]

Thanks to everyone for their great tips. I've discovered more about Dometic fridges than I'd ever imagine I could.

Good news: Mine is fixed, thanks to two very simple moves:

1. Took the orifice right out and cleaned it gently and thoroughly with alcohol. Inspected it to be sure there were no burrs or other impediments.

2. Didn't even bother trying to adjust the regulator. Just bought a good quality new one ($48 Cdn . . . what is that about $13 US? ) and replaced the old one.

The fridge fired up right away, and I could tell the flame was hotter. I'm pretty sure the problem was the regulator. Overnight, froze some food 'cause it was set a bit too high. Now, that's a change! All good. On to the next project.

[Lloyd (aka Santa) Coltman]

Great to hear! Always a worry, when you can't keep food from spoiling.

[gordon2]

Originally Posted by CalgaryEscape

...
2. Didn't even bother trying to adjust the regulator. Just bought a good quality new one ($48 Cdn . . . what is that about $13 US? ) and replaced the old one.
...

I have limited experience but what experience I do have has shown me that even new regulators which are supposed to be pre-adjusted, are often maladjusted. A manometer check is easy enough to make sure.