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Cklost 12-03-2012 02:28 PM

Rheem Gas Water Heater - Model 42V40-40F
I have a Pheem water heater installed exactly 8 years ago and now the pilot light went out. below are the steps I took.

- relit the poilt light - it went out again
- tried to relight and it would not light
- installed new Thermo couple
- Pilot light relit and worked fine
- moved the thermostat to warm, gas kicked in and ignited to heat the water
- after 10 seconds, the flame went out as we as the pilot light
- pilot light would not relight
- pulled everyhting apart and put it all back together, pilot light worked fine, flame kicked in and started to heat the water, after 10 seconds it went out again.
- Seems that the only way to reignite the pilot light is to take everyhting apart, put it all back together and it works for 10 seconds, then it goes out and nothing.

Any ideas as to what could be going on? Should I buy a new gas valve?

Thanks for any help,


sgip2000 12-03-2012 02:40 PM

Might be getting some air in the line.

AllanJ 12-04-2012 08:11 AM

Is this one of the models with a sealed combustion chamber (gasket and glass viewing window on the hatch cover)?

The air intake damper may have triggered. Then the burner and pilot light used up all the oxygen in the combustion chamber. (After several hours, some fresh air will infiltrate.)

You will need an experienced person to reset it, possibly needing a part with a small glass bulb similar to some fire sprinkler heads.

Using or leaking chemicals and cleaning fluids in the basement can trigger the water heater air damper.

Most likely the burner and gas valve and thermocouple and aquastat and other "mechanical" parts are/were okay. The serviceman should clean the burner while he is there.

"Things" should not be "stored" against the water heater. This could block the combustion air inlets.
