Water heater Woes

[John Greenlee]

Here is my situation. In my newtome 66 Overlander I have not been able to make the water heater function correctly. My original problem is that the pilot would burn but the main burner would not kick on. I came to the conclusion that a new control valve was required. I bought a new Robertson control valve with the correct size connections from Camping World. I installed it, but have not been able to make the pilot stay on consistently. (The control valve and the main burner work great now.)

I came to the conclusion that the thermocouple was not in the flame the correct amount. I had read and been told that the last 3/8" or so had to be in the flame. Mine was extending beyond the flame. I tried pulling it back some, cleaning the pilot burner, and wringing my hands. I decided, "Hey, maybe the pilot pressure is too low." I tried turning the screw this way and that, and now have it where I cannot get the pilot to light or make a flame bigger than a tiny one that only lasts a few seconds. What could I have done wrong?

What advice does this forum bring?

Thanks,

JMG

[SilverToy]

JMG -

Thanks for posting the question as I also have a WH issue so I am following your question/issue with great interest.


Not that I have ANY idea of what I am talking about, there are often lenghty discussions of 'sail switches' mentioned, when the pilot light goes on but then won't stay lit for long.....

Experts, PLEASE pile in here and save me from .....

Thanks again for posting the question we 'all' (me + JMG) want answered!!!!

Peace

Axel

[juel]

Hey, here's the woman's point of view. Replaced the WH in my 78 Argosy with one of those new gas/electric ones. Now I just flip a switch and it's on. Of course it works perfectly on the gas too, but I hardly ever use that. I struggled with the older "original" equipment issue for several things on this Argosy, and finally decided I would replace those things that were just trouble. I decided to be "comfortable" and make my trailer what I wanted. This WH is one of my best purchases. Lots of peace of mind.

[dwightdi]

Sounds like dirt in the pilot light burner exit. Dismantle and see if you can blow thru it. The hole is very small but sometimes you can clear it with a single brissell from a steel wire brush. Be careful to not enlarge the hole.

[lewster]

Originally Posted by SilverToy

JMG -

Thanks for posting the question as I also have a WH issue so I am following your question/issue with great interest.


Not that I have ANY idea of what I am talking about, there are often lenghty discussions of 'sail switches' mentioned, when the pilot light goes on but then won't stay lit for long.....

Experts, PLEASE pile in here and save me from .....

Thanks again for posting the question we 'all' (me + JMG) want answered!!!!

Peace

Axel

Axel,

A sail switch is found in a furnace. It is also called an air prover switch, as it's function is to 'prove' to the igniter board (or similar componentry) that the blower is operating and moving the required amount of air before burner ignition will occur.

In a pilot model water heater, the thermocouple must be at a pre-determined (read instructions) distance and position relative to the main burner. It is the job of the thermocouple to open the gas valve when it's pre-determined temperature is achieved and allow the gas to flow to the main burner. There is also a thermostat that will tell the gas valve when to come on (when the water temp. is low and needs to be re-heated) and when to shut off (when the pre-set upper water temp. is reached.)

That's about it on pilot models. No fancy computer igniter boards. No electric elements.....just basic LP components. I would start by cleaning EVERYTHING in the burner tube and burner. Then verify that the thermocouple is operating to spec., then verify that the thermostat is working, then check the gas valve and be sure that it is opening from direction of the thermostat and thermocouple and is allowing the proper pressure of LP to the burner (11" W.G.), THEN re-assemble and light 'er up! .

If you need specific information about the operational sequence, PM me and I'll find some diagrams that I know I have in my archives.

[John Greenlee]

I dismantled and cleaned the orifice already. Soaked it in CLR. You can see light through the tiny hole. I think I have verified that everything else you mentioned works though I have no method to measure gas pressure.

What else?

JMG

[lewster]

Sounds like you might need a new pilot assembly, since you already have a new t/couple. There might be the smallest internal blockage in the pilot supply tube that is preventing it from getting sufficient fuel, thus causing the t/couple to not provide any voltage and not open the gas valve......no flame.

[John Greenlee]

Lew,

Are these pilot assemblies a standard off the shelf item?

Thanks,

JMG

[ticki2]

If the pilot was working before it should be working now. Sometimes scale or other debris gets lodged in the regulator because it has been disturbed . I believe there is an internal pilot filter in the regulator valve . If you still have the old one take it apart and see , perhaps Lew has a diagram that would help

[lewster]

Originally Posted by John Greenlee

Lew,

Are these pilot assemblies a standard off the shelf item?

Thanks,

JMG

John,

What is the make and model of your heater? I'll check my resources for some diagrams and schematics.

[John Greenlee]

Lew,

My trailer is a 66 Overlander. The heater is the original Bowen. Is this enough information? The valve I used is not, I am sure, a direct replacement. It is simply an RV valve with the correct size fittings.

Thanks,

JMG

[WayWard Wind]

John
I see where you mention that you turned the pilot screw this way & that. I've seen where grease/dirt has gotten into the way for the pilot gas to flow thru to the pilot. I'd suggest that you try (backing) the pilot adjustment screw way out, press down on the control, as if you were going to light the pilot ( which by the way do not have a flame near) and then see if you can get gas to flow thru the pilot adjustment. Sounds to me that once you turned the pilot adjustment screw you lost the gas flow. If you're not comfortable working with LP, then I'd also suggest that you take it to a certified LP service.
Best