Fridge cools on A/C but not on Propane - EDIT: FIXED!

[cpachristopher]

Hi All, I've been several years with out a TT, but wife convinced me it was time to jump back in, and so far so good, except for the fridge.

I'm pretty handy, but I called for help on this one. The repair guy came out and was baffled.

It is a Dometic, very small, no adjustment knobs anywhere. Trailer is a 2015 model so I assume the fridge is, too.

Here's the situation:

Load fridge @ Home while plugged in to shore power. It worked reasonably well. We went camping and switched to propane. Within 24 hours it was clear that the fridge was not cooling. Fortunately we had a cooler, so it worked out.

Fast forward to the next week. I had the TT parked at home on shore power. I put a case of bottled water in it, and it brought the temp down nicely. I unplugged power and switched to gas and within 2 days, the bottles barely below ambient temp..

Service guy came out - we checked and saw flame. The cooling fins are warm. The check light is NOT on.

He poked around and scraped some soot off and said that I should try again and make sure I had flame,

So....Pre-camping last week I loaded the fridge with bottles of water again. The odd thing is that the freezer (tiny, but internal to the fridge with a fold-down door) was really cold - icing up on the floor of the fridge. However, the fridge itself was not cold. I took the door off of the freezer and left the bottles inside, and sure enough, they got nice and cold - all on A/C

So, what the heck am I missing here. It seems I have flame. The A/C power is clearly heating the ammonia enough to chill the thing. And I have a freezer but not a fridge, but only on A/C. I rarely have A/C when camping,

I'd really love to avoid buying a new fridge but that is 1/3 of the reason my wife wanted another trailer (1/3 being bed off ground, 1/3 being shower)

I'm not home else I'd get the model of fridge.

Trailer is a 2015 Coachmen 16FB

If anyone has any ideas, I'd love to hear them.

[MrWizard]

it is the intensity and color of the flame
The fact that you can hear it, is an indication of the fuel air mix being correct,

Like you said, you can really see the difference with stove burners

[cpachristopher]

MrWizard wrote:
see... NOW you know the difference
take a good look at Flame the fridge burner produces Now

the flame you have now is correct, and the one you thought 'looked' good before,
did not produce enough heat

I THINK it looks a little bigger. Hard to say for sure.

In any case, it sure works better.

[cpachristopher]

When it kicks in, I can hear it. The cover is off the heat exchanger and I can feel a difference, too - meaning it is much warmer than it was before changing out the regulator.

pnichols wrote:
cpachristopher,

I'm curious ... can you now hear the low roar of the burning refrigerator flame when standing outside the coach beside the refrigerator's air intake?

[dougrainer]

cpachristopher wrote:
Thanks to those who helped. I installed a new regulator ($40 and 5 mins of my time) and let it run all night on propane. The fridge is full of nice, cold bottles of water.

I am more than a little pissed that the "professional" RV repair guy I hired didn't even mention it or test the propane. I sure didn't know about it, but I'm just some office dweller!

Thanks again. Going camping this weekend with a cold fridge will be nice.

I take exception to you calling that Parts Changer a "professional". The problem with ALL walks of life is, there are people that claim to be Experts or Professional's and they only have a little knowledge, but enough to muddle thru. The sad part is YOU must pay them to come to you and then have no recourse when they do NOT have the expertise to fix items that DO TAKE Professional Knowledge. That is why most Mobile Techs require cash up front. The BAD ones want cash while real professionals usually will accept Credit Cards. Doug

[dougrainer]

pnichols wrote:
Hmmm ... after reading this thread, I'm scratching my head as to what a new gas regulator might have to do with the OP's problem? If the flame is the proper size and makes a loud enough burning sound ... then how can a new regulator do anything?

I suspect something else is wrong with the refrigerator that is causing electric heat to have an effect that flame heat doesn't have. Isn't a BTU a BTU?

DID YOU NOT READ MY POST? It explained why the LP pressure is critical and you cannot tell from the sound or size. Doug

[pnichols]

cpachristopher,

I'm curious ... can you now hear the low roar of the burning refrigerator flame when standing outside the coach beside the refrigerator's air intake?

[MrWizard]

see... NOW you know the difference
take a good look at Flame the fridge burner produces Now

the flame you have now is correct, and the one you thought 'looked' good before,
did not produce enough heat

[cpachristopher]

I replaced the main supply regulator.

Funny, when I lit the stove to get the propane going, it put out a much better flame than before!

[time2roll]

You replaced the regulator at the main supply?
I don't think the fridge has a regulator.

I would have recommended Cavagna brand but with a single bottle they are probably all about the same. How old was it? IMO about 5 to 10 years and they are high suspects to trouble.

[Boon_Docker]

You better replace those cold bottles of water with cans of beer before you go. :B

[cpachristopher]

Thanks to those who helped. I installed a new regulator ($40 and 5 mins of my time) and let it run all night on propane. The fridge is full of nice, cold bottles of water.

I am more than a little pissed that the "professional" RV repair guy I hired didn't even mention it or test the propane. I sure didn't know about it, but I'm just some office dweller!

Thanks again. Going camping this weekend with a cold fridge will be nice.

[pnichols]

Hmmm ... after reading this thread, I'm scratching my head as to what a new gas regulator might have to do with the OP's problem? If the flame is the proper size and makes a loud enough burning sound ... then how can a new regulator do anything?

I suspect something else is wrong with the refrigerator that is causing electric heat to have an effect that flame heat doesn't have. Isn't a BTU a BTU?

[cpachristopher]

Yesterday I cleaned the burner (gently as noted above) and ran a bore snake through the flue. This morning, the fridge was warmer than last night, and the heat coming off of the cooling fins was not nearly as great as the heat when running on A/C.

At this point, I think I'll buy a new regulator, since every web-site I've looked at since you folks pointed it out suggested I carry a spare in any case. If it doesn't fix the problem...no clue, but if it does, I'll be thrilled.

Looking for a regulator, do I just buy an exact match of what I've got or is there a suggestion for a "better" one? I don't plan to run two tanks.

[billyray50]

dougrainer wrote:
If it works on 120 and not good on LP and the flame "looks" OK. THE FIRST THING ANY COMPETANT TECH DOES IS VERIFY THE LP GAS PRESSURE. NOT doing that shows lack of knowledge and skill and I would not hire/use this part changer anymore. A 1 inch drop in LP pressure will have a drastic affect on the cooling capability and you will not be able to tell by the flame size/look. Doug

That's what was going with mine. 4 year old regulator was bad. Installed new regulator and works fine now.