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Thermocouple heats up to a red color. Flame covers about 90% of its length I didn't use pipe dope on the threads. I also measured voltage on my old thermocouple and it went up to 32mV. Didn't measuse it on new one, figured it wasn't the problem.
I pulled it out so the flame was covering only 1/3 of the tip and tried going through start up process several times. It still doesn't stay lit.
Is it too much moisture in the air or gas line needs to be purged?
It's plain thermocouple labeled:
18" Universal Thermocouple
Please check the millivoltage on the new thermocouple, or put the old one back in. This sounds like the new thermocouple may have either been bad from the start, or is now bad. Rick has covered all the bases. Your new t couple should produce at least 20 millivolts.
I assume by "thermopile" you are refering to thermocouple. I disconected it and hooked it up to multimeter. Turned on the pilot and it went up to 28mV and was still slowly climbing up.
Yes, I had edited my post just soon after I proof read it.
Did you replace the gas valve with the exact same model? It sounds as though there is no connection being made at the valve from the couple. Also check to make certain, none of the control wires are accidentally being ground out. This will prevent the pilot from staying on.
Just checked TH and TR and they are not connected to the ground.
My old gas valve was 36CO3 Type 221.
The replacement is 36C03-300. I used 1/3" to 1/2" adapter on the outlet line. The box was labeled with adater included, but it wasn't in the box, I had to buy it at Home Depot.
Do you want me to remove E.C.O. jumper as well?
Disconected TH and TR wires and made sure thermocoupler connection is not overly tight. Did'nt help.
Thanks for your help. Hope someone else has the answer.
I am coming to the same conclusion. I will order another valve by express shipping and if that's the case I will give you satisfied answer. Will have to wait a few days and see