Mnalep
Member
I have a problem with the new combination (White Rodgers 36C03U-433) valve that I just bought and installed on my milllivolt (thermopile generator) on Luxaire SH-125 gas furnace.
The old valve had a pilot line that was fed off of a separate gas cock mounted just before the main gas cock valve.
This is different from the new installed WhiteRodgers 36C03U-433 valve where the pilot line feeds out of, and is controlled by, the new combination valve. Could this be the reason the pilot goes out on high LIMIT - it is no longer independant of the combination valve control unit?
The new valve seems to work fine up until the point where the limit switch is tripped - and at that event the combination valve 'clunks' and main burners close - and the pilot flame goes out. So at that point the furnace is no longer operational unless I manually relight the Pilot.
The millivolts reading was 400 Mv on my new combination valve at the TH-PG and PG terminal screws with only the Pilot on. It drops to about 375 Mv when the burners come on.
When the LIMIT activates and turns the main burners off, the millivolts readings immediately drop, and the main burners AND THE PILOT flame both go off. (That is how I knew the pilot went out at that moment - the millivolts sudden drop and observation that pilot was out.)
Could I have a faulty gas valve (even though it's brand new)?
The Thermopile generates 400 MV while connected to the combination valve. I think that is adequate?
I am really stumped. I can even turn the gas cock on the combination valve off, and on, several times, and the PILOT stays lit while the burners go off and on. The PILOT stays lit when the main burners fire up, and when the blower motor comes on.
It seems wrong that the LIMIT switch should turn off the main burners and the PILOT FLAME! Seems the Pilot Flame should continue to be fed gas even after the main burners shut off.
Is my new gas valve (White Rodgers 36C03U-433) not compatible?
My old valve was a Honeywell VS87A9X4X2, for the thermopile generator pilot.
Thanks, Matt
The old valve had a pilot line that was fed off of a separate gas cock mounted just before the main gas cock valve.
This is different from the new installed WhiteRodgers 36C03U-433 valve where the pilot line feeds out of, and is controlled by, the new combination valve. Could this be the reason the pilot goes out on high LIMIT - it is no longer independant of the combination valve control unit?
The new valve seems to work fine up until the point where the limit switch is tripped - and at that event the combination valve 'clunks' and main burners close - and the pilot flame goes out. So at that point the furnace is no longer operational unless I manually relight the Pilot.
The millivolts reading was 400 Mv on my new combination valve at the TH-PG and PG terminal screws with only the Pilot on. It drops to about 375 Mv when the burners come on.
When the LIMIT activates and turns the main burners off, the millivolts readings immediately drop, and the main burners AND THE PILOT flame both go off. (That is how I knew the pilot went out at that moment - the millivolts sudden drop and observation that pilot was out.)
Could I have a faulty gas valve (even though it's brand new)?
The Thermopile generates 400 MV while connected to the combination valve. I think that is adequate?
I am really stumped. I can even turn the gas cock on the combination valve off, and on, several times, and the PILOT stays lit while the burners go off and on. The PILOT stays lit when the main burners fire up, and when the blower motor comes on.
It seems wrong that the LIMIT switch should turn off the main burners and the PILOT FLAME! Seems the Pilot Flame should continue to be fed gas even after the main burners shut off.
Is my new gas valve (White Rodgers 36C03U-433) not compatible?
My old valve was a Honeywell VS87A9X4X2, for the thermopile generator pilot.
Thanks, Matt