View Full Version : water heater pilot light problems
12-16-2008, 10:42 AM
The pilot light in our new (~2 y.o.) water heater (a State Select High Efficiency) keeps going out, a couple times a day. The problem just started a few days ago when the rains started. I don't think it's a thermocoupler problem because the pilot light easily lights, and I don't think it's a combustion air problem because it's in our laundry room, not in a closet, and is open to the entire inside of the house. The unit was installed professionally with good ducting, earthquake strap, spill pan, etc.
So I'm wondering what else might be causing the light to go out. I'm wondering if it's possible that we're not getting enough pressure. The water heater is the last appliance on the gas line, after the wall heater and the stove. Is it possible that the pilot light goes out intermittently if the other things are in use? And if so, how would I diagnose low pressure? And what other causes might it be?
12-16-2008, 12:37 PM
Most cases, it is a bad or mis-adjusted thermocouple or partially plugged pilot.
Test the thermocouple by blowing out the pilot (leaving the gas valve on, and turning down the thermostat).
If you hear the gas valve click off in 25 seconds or less, the thermocouple is bad. 25-60 seconds is okay.
Does the pilot look and sound strong? If the thermocouple is good, and it is adjusted so that the pilot hits it full force, you can clean out the pilot orifice with a special wire called a pilot broach.
If neither of those solves your problem, I would look closer at the ducting.
Downdrafts will extinguish the pilot light.
master plumber mark
12-17-2008, 04:59 AM
If this is the new FVIR type made after 2003
then you probably got problems...
PERHAPS it needs a new Gas Valve, but
you mentioned that it was in a laundry room,
so that tells me that the bottom of the unit is already clogged up
tons of with lint.........
I have tangled with them before and you will have
to take the whole assembly out of the front of the heater,,
then you will have to get a air compressor with a hose and
blow down through the air intake screen to get all the lint
out of the heater... (see pics)
you will have to blow it out from the bottom. from under the heater also..
you will need to change the little crappy high limit and thermocoupling inside the heater also,
when you put it back together , remember that they need all the air
that they can get, and sometimes it works better without tightening
back down that front seal...
here are some pics for you to see what you are dealing with
I have tangled with a good number of them, and the ones
that beat me after changeing out everything,
were torn out and cut open on my operateing table.
scroll half way down this page and you will see your State select heater..