Date: Sun, 5 Aug 2012 12:30:09 -0400
Reply-To: David Beierl <dbeierl@ATTGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: David Beierl <dbeierl@ATTGLOBAL.NET>
Subject: Re: Refrigerator gasket and flame goes out remedies
In-Reply-To: <op.wikqncm2flv9uo@felix.onebeam>
Content-Type: text/plain; charset="us-ascii"; format=flowed
At 11:29 AM 8/5/2012, Leonard Sitongia wrote:
>Hi,
>
> I have the Dometic 182 refrigerator out of my Westy and I'm trying to
>address the problem in that it won't stay lit. Spark is okay. Ignites.
>After minutes, the flame goes out.
Thermocouple seems a likely possibility.
> The thermocouple wire insulation is frayed at the point where it makes a
>bend to the burn box. Looks like the wire is intact. Maybe I should
>replace it.
Are you sure that's not the sparker? As I recall the thermocouple
uses a solid copper tube. For the sparker, a glob of your silicone
stuff (non-acetic acid curing) should take care of the insulation.
> How can I test it on a bench?
There's a terminal on the gas valve where the ?black? wire plugs in
that leads eventually to the flame sensor. Measure voltage between
that and the valve body, should see in the negative several hundred
millivolt range. If you turn the flame to pilot and that drops and
flame goes out, I'd be pretty confident of the thermocouple being the problem.
Perhaps someone with a working fridge can measure the operating
voltage there with full flame and pilot flame. It's not necessary to
pull the fridge as you can measure at the LED panel.
> Can I power the fridge on 110v
>and use water to test it or does that risk damaging the thermocouple
>sensor, especially since there is fraying.
I don't understand the test you're contemplating. Please be much
more specific. The thermocouple does not enter into 110 V operation
in any way.
> The gasket (the one with the six screws through it) on the burn box had
>cracks. I've used Ultra Copper high-temp silicone to REPLACE the gasket.
>Now I just re-read a site that suggests the silicone be used ON the old
>gasket. My first QUESTION is, did I screw up? I thought that the silicone
>is a gasket MAKER, not a sealant. Do I need to put the old gasket in WITH
>the sealant on both sides of it?
You did not screw up. It's probably a good idea to make up your new
gasket to roughly the thickness of the old one, about 1/8" if I
remember correctly. You do this by tightening to a bit thicker and
letting it cure for a while, then tightening down to thickness.
> My other QUESTIONS are regarding the troubleshooting of this problem from
>the Dometic Service Manual (RM182B Edition 2, August 1982). The chart on
>p. 10 relates possible causes referring to parts that I don't have an ID
>for.
>
> The "safety valve" is connected to the button you hold in while lighting,
>right? It has a "valve magnet"? How can I troubleshoot this?
Best way is with a known good thermocouple and a flame.
> Where is there "gauze in the burner head"? When I took the burn box
>apart, there's a tube with slots in one end, which is where I assume the
>flame is. Is there supposed to be gauze in that tube?
No. There's a filter of some kind upstream (in the gas
valve?). Pull the orifice and soak in denatured alcohol (or
Everclear) for a while, then blow out with compressed air. Do Not
put anything solid in/through the orifice as you'll probably wreck it.
> Where is the "By-pass flame"?
The thermostat valve has two passages, a main one for the full flame
and a restricted one for the pilot flame. They must be calling the
pilot the by-pass flame since it by-passes the thermostat.
Yours,
David
