Puzzled by Refrigerator Problem

[rfloyd99]

I'm getting ready for a trip, and can't figure out what's going on with the Dometic fridge in my six year old trailer. FWIW, we didn't use it at all for a year.

Yesterday I tested the stove, water heater and fridge. All worked, I left the fridge on for a couple of hours, and it was working, starting to get cool. The gas burner fired right up.

Today I took both propane tanks to be filled, came back and hooked them up and tested everything again. All worked except the fridge. When I set it on gas, I never heard the clicking sound to light it but I could see what seemed like a burning pilot light inside the firebox area. But the burner never fired. I tried it several times. When I set it on electic, the pilot light disappeared, but came back every time I set it on gas. I've never had any trouble with the fridge over many trips. Of course, there are no service people available where I am.

Anyone have any ideas?

[Gjac]

I understand what you mean by a roar I can hear mine also when I turn it on. If you have not cleaned the burner tube in 6 years I would do than first. Not only do rust flakes fall down from the chimney on the tube blocking the slots reducing the flame but very fine rust gets through the slots and will build up inside the tube and will reduce the flame size also. It is very easy to remove and clean and at the same time clean the orifice with alcohol. I vacuum mine out every season.

[stevenal]

I've had two campers in my life, and both had regulators that were improperly set until I adjusted them. Either get a manometer, or find an RV servicer with one.

[opnspaces]

wa8yxm wrote:

rfloyd99 wrote:
Eddie, there was SOMETHING not working right. the little flame I could see was not the main burner. When the main burner is on you can see a bigger flame, and also can hear the "roar" of the full combustion.

MT Bob, hope you're right and it'll work for the next month (or several years!) I'm making a big note about the fuse trick.

Anyway, I went back out an hour or so after it finally fired up and it's still working. Keeping my fingers crossed....

I do hear a roar on the water heater
But NEVER on the refrigerator. NOT once it is a small flame only 300-400 watt equivlent.

YOu might need to clean the burner orifice.. But See if it gets cold..

I can hear my refrigerator making a small roar when I walk buy the outside access panel. In a really quiet camp spot I can sometimes barely discern it sitting inside the trailer. It's not a roar like the water heater, but it is a minute distinct roar.

[wa8yxm]

rfloyd99 wrote:
Eddie, there was SOMETHING not working right. the little flame I could see was not the main burner. When the main burner is on you can see a bigger flame, and also can hear the "roar" of the full combustion.

MT Bob, hope you're right and it'll work for the next month (or several years!) I'm making a big note about the fuse trick.

Anyway, I went back out an hour or so after it finally fired up and it's still working. Keeping my fingers crossed....

I do hear a roar on the water heater
But NEVER on the refrigerator. NOT once it is a small flame only 300-400 watt equivlent.

YOu might need to clean the burner orifice.. But See if it gets cold..

[MT_BOB]

Yes,tank regulators go bad,quite a bit.Not uncommon at all.I carry a spare.
But,it is always nice to have the pressure checked,with a manometer, even the new regulators. You can quickly and cheaply slap together a water tube manometer, instructions on youtube and the net.

[dougrainer]

This test is NOT foolproof but works most of the time. Light the range stove top burners. Then Run the Furnace, the water heater and refer on LP. At the same time. Watch the Range burners as the various appliances come on. IF the flames on the range burners diminish or go out or pulsate, your LP regulator is bad. While there is an adjustment on the regulator, it is best to replace it. Doug

[rfloyd99]

Well, it never really "roared", that's just the first word that came to mind to describe the "sound it makes when the flame ignites". I usually sent my wife to listen for it when we set up camp without electicity. Her hearing is better than mine. It's much quieter than the WH, which does kinda "roar".

I think I do have some sort of LP pressure regulation issue that has caused all this. When I reconnected my tanks I was probably guilty of not opening the valves slowly. I reconnected them as mentioned above, and the problem is better, but I'm not sure it's normal yet. The fridge seems to be working fine, fires right up, flame stays on, unit gets cool. However, when testing all the LP appliances, the burners for the WH and stove (both easier to observe the flame than the on the fridge) don't seem to burn as well as they do when only one appliance is on at a time. We have spent six, three and four months at a time on the road (plus several shorter trips) over the last five years, so we know how things worked in the past. BTW, we never use the furnace, even if it's cold enough to need it, which is rarely the case in our travels.

The month-long 3,000 mile trip we're starting next week will be mostly using CGs with hookups, and after the first 10 days will be at much lower elevation than where I am now (5,000 ft). The elevation could play a role in my LP issues, although my experience has been that there hasn't been an effect until you get up around 7,000 feet, and then it only affected the fridge.

My other guess is that the regulator at the point of connection to the tanks isn't working properly. A local RV service place says their supplier has been out of those for months. Has anyone had issues with those regulators?

[aftermath]

rfloyd99, You have gotten a lot of excellent, and accurate, advice. Opening the valve on your tank can cause many issues.

My take on all of this is, you never had a problem. When you run the fridge on propane it takes some time to cool down. I found that it actually takes longer when on electricity. I listen carefully for the click and can hear the flame ignite. It NEVER roars, and if it did I would turn it off quickly. Something is wrong if you hear this.

Pay attention to the back side, where the access panel is. Keep it as clean as you can. Vacuum out, or blow out the dust and cobwebs if there are any. It doesn't take much to block the flow to the burner.

As long as you see the flame, you are good to go.

[vermilye]

If you are hearing a roar from the refrigerator flame, even if it cools, you have a problem. I've never heard a refrigerator flame roar...

[BobsYourUncle]

Another thing I didn't think to mention:

You said it happened after filling and reconnecting the bottles.
There is a safety feature built in to the valve / tank that will restrict or cut off the flow in the event of a sudden change in the flow.
This is to cut off the gas flow if a line gets severed in an accident or something, so that the gas does not flow freely and cause an explosion or fire.

I once activated that safety feature after filling the bottle by turning the valve open very quickly. The solution was to shut it off, disconnect the hose, reconnect and open the valve slowly instead of cranking it quickly.
But that doesn't really explain why other appliances worked.
Just a thought.

[rfloyd99]

Thanks for all the additional info re the flame, pilot light, etc. I understand there isn't a pilot light on this type of ignition system, and I shouldn't have called it that. BUT, when the unit worked on day one of my testing it, I heard the "roar" that it always makes when burning properly over the last five years of use, and it started cooling.

The next day, after having the bottles filled and reconnected it wouldn't fire. So I took off the plastic cover and looked into the combustion chamber, which can be viewed a little without removing the shield. When the unit was on gas mode, there was a little flame visible, but no sound of combustion. When set to electric mode, that flame wasn't there. Believe me, I tried this change of mode and stared at it repeatedly. Late in the evening, I tried it again and it fired, roared, and I could see a much larger flame in the same place. An hour later it was still working and the temp in the fridge was falling.

It seems that the little flame was the result of debris or reduced pressure as you guys with more experience have said. This must have somehow corrected itself and it fired normally. I haven't been out to see if it's still working today, but will let you know. I've recounted all this for the benefit of others who may be following this; I'm sure I'm not the only one who needs educating. I'll access and clean the burner as suggested.

Thanks again!

[dougrainer]

IF the refer starts working on LP, then no problem. BUT, if it fails to cool correctly on LP but DOES when you plug into 120 volt, then you need the LP gas pressure checked. AS others mentioned, there is NO PILOT FLAME on your model. Just the regular flame. But, if your LP pressure is slightly LOW, then the cooling capacity is diminished. This will manifest in what you state is NOT a roaring flame. But, it is extremely difficult for anybody to just look a a Refer flame and state that the LP pressure is below spec. Doug

[BobsYourUncle]

Wa8yxm is 100% right.

There is no pilot light on DSI appliances. A 6 year old unit will be DSI.
If you see a flame, it is the burner, not a pilot light.

However!

The main tube where the burnt propane vents out the top of the fridge, which is directly above the burner, can be prone to surface rust. This rust becomes loose and little flakes will settle down onto the top of the burner, effectively partially blocking the little holes of the burner. The flame can become reduced in size, even until it resembles a pilot light. Reduced flame = reduced heat = reduced cooling.

I have had to clean mine on various fridges I've had.

Take the outside cover off the fridge and look. There is usually a wind deflector in front of the burner, removable by taking out a screw holding it in place. This will expose the top of the burner, where you can inspect it for debris, and get in there with a shop vac, outfitted with a reduced size nozzle, and suck stuff out of there.
I further use compressed air and blow everything clean in there, including the long tube feeding gas to the burner. There is an adjustable hole in that tube where you can blow it out too.

Every time I have done this I have seen a noticeable difference in flame size and quality, and unit performance.

[wa8yxm]

rfloyd99 wrote:
like a burning pilot light inside the firebox area. But the burner never fired.

There is no pilot light on a direct spark ignition system
What you think is the pilot light is the actual main burner
The fridge burner is not much larger than a 1950's stover or oven pilot light. Not much bigger than your rV oven's pilot light. ONly needs to make about 300-400 watts worth of heat. that's not much heat.