fridge problems

[wvsafari]

We just started working on our newly acquired 69 safari and discovered that among other things, the fridge needs work. It is out of the camper and we have full access to the back. When propane is lit, the tube out of the top of the heat chamber stays hot until it reaches the top square set of coils..then it stops and no heat transfers to the end of the set of coils and no cooling occurs. This is our first question .. will most likely have many more.. any help on fridge repairs would be much appreciated. The fridge is in great shape so we would like to keep it before talking about replacement options.

[Inland RV Center, In]

Originally Posted by wvsafari

We just started working on our newly acquired 69 safari and discovered that among other things, the fridge needs work. It is out of the camper and we have full access to the back. When propane is lit, the tube out of the top of the heat chamber stays hot until it reaches the top square set of coils..then it stops and no heat transfers to the end of the set of coils and no cooling occurs. This is our first question .. will most likely have many more.. any help on fridge repairs would be much appreciated. The fridge is in great shape so we would like to keep it before talking about replacement options.

Sounds like the cooling unit is bad.

The final check would be to test the fridge on city power.

Andy

[Jared129]

May we look at the other side of the coin? What would be the most likley reason the fridge would work fine on propane but does not run on city power?

[Chaplain Kent]

Originally Posted by wvsafari

When propane is lit, the tube out of the top of the heat chamber stays hot until it reaches the top square set of coils..then it stops and no heat transfers to the end of the set of coils and no cooling occurs. .

Sounds to me like you have a carbon build up in the flue, a simple fix. First check if you are getting any heat out of the top of the flue, if not, all you need to do is clean that flue. There are several threads here on doing the cleaning. I have never done mine with the unit out only while the fridge was still in the coach. What I do is use a small wire and insert up the tube until all the carbon is loosened. Then I use my air compressor and blow it out. This has worked fine for when the flue was clogged and now on regular maintenance.
Good luck to you.

[herrgirdner]

Good advice, CK. If it works on city power and not on propane, that is a likely cause.
There are several threads on fridge problems on this web site. Suggest you review them before going much further.
regards

[azflycaster]

Originally Posted by Jared129

May we look at the other side of the coin? What would be the most likley reason the fridge would work fine on propane but does not run on city power?

Heating element open?
Bad gas/electric switch?
Bad electric temperture switch?

I would meter the heating element first, if it's open, get a new one.

[lewster]

Originally Posted by wvsafari

We just started working on our newly acquired 69 safari and discovered that among other things, the fridge needs work. It is out of the camper and we have full access to the back. When propane is lit, the tube out of the top of the heat chamber stays hot until it reaches the top square set of coils..then it stops and no heat transfers to the end of the set of coils and no cooling occurs. This is our first question .. will most likely have many more.. any help on fridge repairs would be much appreciated. The fridge is in great shape so we would like to keep it before talking about replacement options.

A thorough cleaning as Kent suggested is a great idea with the fridge removed. First, after removing the propane burner, removing and cleaning the spiral baffle located in the chimney and swabbing the entire length of the chimney, replace all components. Then, and I shudder at saying this , but I would 'burp' the fridge. You can check the thread on burping that we did in Albuquerque in June of this year. It means laying the unit flat on each side for 5 minutes a side, including the top.

Then, with the unit upright, tilt it on all 4 sides for 1 minute each. After all of this, connect it up and run it and see what happens. You are essentially doing this to break up a blockage in the tubing which sometimes happens from sitting inoperative for an extended time. Sometimes it works, sometimes not, but it doesn't cost anything and is sure worth a try. The unit we 'burped in ABQ is still going strong!

Have fun!

[lewster]

Originally Posted by Jared129

May we look at the other side of the coin? What would be the most likley reason the fridge would work fine on propane but does not run on city power?

Jared,

First, you should do a continuity test on the element to see if it is good. If no continuity, replace it, as this is the problem.

If the element tests OK, then it might be a control board problem. A quick test for this is to remove the leads for the element at the board, make a pigtail with a 120VAC extension cord and 1/4" male connectors on the other end, and plug the element directly into a 120VAC outlet. Give it a couple of hours, and you should feel heat at the chimney burner section. If it works with the direct application of 120VAC, you need a new control board.

[wvsafari]

Thanks to all for your helpful responses... we will give them a try. Right now, we find ourselves installing new plywood flooring as we discovered the water heater had a leak and over the years (?) soaked the wood and caused subsequent rot.
This is a growing project! Appreciate your collective advice

[bilby05]

Originally Posted by lewster

First, you should do a continuity test on the element to see if it is good. If no continuity, replace it, as this is the problem.
-----
Did this test. got 40 ohms of resistance. That means it ok? right?
------------------
If the element tests OK, then it might be a control board problem. A quick test for this is to remove the leads for the element at the board, make a pigtail with a 120VAC extension cord and 1/4" male connectors on the other end, and plug the element directly into a 120VAC outlet. Give it a couple of hours, and you should feel heat at the chimney burner section. If it works with the direct application of 120VAC, you need a new control board.

-------------
Gonna try this test next.
---------------------
This is what I have encountered so far:
Background:

Dometic S1621, Two way, Automatic Manual Energy Selector (AMES) 110V or LP Gas

Fridge is about 10 years old.

The problem:

Turn on the fridge, set to automatic, it automatically starts with gas. The "lighter" goes click-click-click. If the gas is turned on it starts and runs on gas. If the gas is not on it attempts to restart again in a moment, but does not select AC. In the past I have started it on gas and after awhile switched over to electric and it would continue to operate on electric but seems to eventually stop working and switches to "check light" on.

Things I have checked:
Main 12v terminal block has 13.2 volts going in and going out to lower panel.
Main 110 volt plug-in for fridge registers 115 volts.
Pulled J7 and J8 from the board to check the resistance for the 110 volt heater: was 40 ohms
This unit does not have a 12 volt heater.
Both fuses seem to be ok.

To do(as per instructions in Dometic Troubleshooting guide)
Check both fuses again for continuity.
Measure 12v voltage from J4 to ground strip. Should be same as main 12v voltage.(or would this just be for the 3 way systems that have a 12volt operating option-mine doesn't)
On AC mode (which I can not get to "stick") check voltage at J5 and J6 (would that be J5 to ground and J6 to ground or J5 to J6?)
Check for voltage at J7 and J8 (J7 to ground and J8 to ground or J7 to J8?)

Any other suggestions? Is there a simpler way to find the problem? Iam going to try the top listed suggestions by lewster. Or is there a way to run the thing on 110 only, bypassing the complex auto switching system?

[lewster]

bill,

You can run the unit on 120VAC only and bypass the control circuitry by removing the leads for the 120VAC heating element and going directly from the 120VAC outlet to the element. Please note that this is for testing only, as you will then be turning your entire unit into a freezer as there will be no controls to regulate the interior temps within the fridge section.

All Dometics that have the AMES system have a priority to operate on 120VAC if it is present. If yours will not automatically switch to AC operation from LP when the AC is present, then you probably have a bad board that needs to be replaced.

Hope this helps!

[bilby05]

RE:

Originally Posted by lewster

bill,
...run the unit on 120VAC only and bypass the control circuitry by removing the leads for the 120VAC heating element and going directly from the 120VAC outlet to the element...testing only...as there will be no controls to regulate.

All Dometics that have the AMES system have a priority to operate on 120VAC if it is present. If yours will not automatically switch to AC operation from LP when the AC is present, then you probably have a bad board that needs to be replaced.

............................
I will give that a go. I suspect that the board is bad, based on the "default to AC" normal setting. I have been holding off on the board because of the costs. I hate it when I spend $100 for a part and that was not the cause. But I think this is looking like a sure thing. I hear that Dinasaur makes a replacement board that is supposed to be superior to the original, so I may go with that.
thanks, bill b.

[lewster]

Originally Posted by bilby05

............................
I will give that a go. I suspect that the board is bad, based on the "default to AC" normal setting. I have been holding off on the board because of the costs. I hate it when I spend $100 for a part and that was not the cause. But I think this is looking like a sure thing. I hear that Dinasaur makes a replacement board that is supposed to be superior to the original, so I may go with that.
thanks, bill b.

Bill,

What is the model # of your fridge? I'll look it up in my Dinosaur catalog. They make the Micro P-711 which is a great replacement board for 'some' Dometics. Let me know and I'll get back at ya'.

[bilby05]

I have ordered the dinosaur board for my trailer, Micro P711 according to the site, and the online instructions seem very good. I will report back when it comes in.
cheers, bill b.

[juel]

The Dometic in my 76 Sovereign works on gas but not on electric. I honestly don't think I understand any of the troubleshooting tips I'm reading. I'm seriously considering a household frig. replacement, keeping the Dometic to reinstall if I ever want to sell this trailer. This trailer will be parked at the lake for extended periods of time and I want to leave the refrigerator running because of the long cool down time for a 31 year old RV frig. I've always hated to see household refrigerators put in Airstreams, but now I'm gaining a better understanding of why people do that. There is a brushed aluminum model at Lowes that will fit the space almost exactly for $278.00. I'm weakening. Is there a 12 step program to help me?

[lewster]

Originally Posted by juel

The Dometic in my 76 Sovereign works on gas but not on electric. I honestly don't think I understand any of the troubleshooting tips I'm reading. I'm seriously considering a household frig. replacement, keeping the Dometic to reinstall if I ever want to sell this trailer. This trailer will be parked at the lake for extended periods of time and I want to leave the refrigerator running because of the long cool down time for a 31 year old RV frig. I've always hated to see household refrigerators put in Airstreams, but now I'm gaining a better understanding of why people do that. There is a brushed aluminum model at Lowes that will fit the space almost exactly for $278.00. I'm weakening. Is there a 12 step program to help me?

Juel,

Sounds like you have a bad heating element. If you have a multi-meter, set it to ohms, unplug the wires from the element that go into the control board and put the meter on the leads. You should get about 45 ohms as a reading. If you get nothing, you need a new element, which is way cheaper than a new fridge for $300.

Let me know if you have any other problems.

[juel]

Could you just stop by here on your way between FL and OR? LOL

[lewster]

Originally Posted by juel

Could you just stop by here on your way between FL and OR? LOL

Sure!

If you could wait until May when I hit the road again!

[richinny]

maybe she could mail it to you to fix ;-)

[juel]

Lewster.....That's so sweet of you. I took the door off outside the frig. and nothing looked like what I've read about troubleshooting. I was thinking about replacing it with a stainless household frig., keeping the Dometic to put back if I ever want to sell the AS. Hate to do that. I really am opposed to people doing that, but now I understand why. $1000.00 plus shipping and labor to install is pretty steep and I want to use my trailer. Since it's 31ft long and my husband works out of state, there is no way I can get this AS out of the property. Maybe mailing the frig. isn't such a bad idea! I have a good RV repair man, actually two of them, but I doubt they make housecalls. Ice chest here I come. Back to the old days for a while.