Ask Me Help Desk - Thermocouple on Old Carrier Gas furnace

If the thermocouple is defective, could you light the pilot and it and the burner would stay lit? How do you know it is defective? Would the defect be visible? If so, could you tell me
What it would look like?
The heater is 20+ years old. I have never had ONE problem with it, until I had it cleaned.
After the tech cleaned it and I cut it on for the first time, there was NO heat. The pilot
Was not lit. The same tech came out, carrying a thermocouple in his hand. He said the
Couple was defective and charged me an additional $130. I thought it was somewhat
Dubious, so I just wanted to verify some of the things he told me and showed me. I would appreciate any help on this.
Susie

Thermocouples can go bad at any time. We suggest to our customers that they be replaced every 5 years. It is much cheaper to do it when we are doing the cleaning than to have to come back out. If the customer refuses the replacement after we suggested the repair, we will charge them full price to come back out later. If the pilot was lit the thermocouple is good, since the pilot light drops out when the thermocouple goes bad. I just want to be sure we are talking about a thermocouple, since most carrier/bryant furnaces use a bi-metal auto pilot, these are completely different from a thermocouple.

Quote:

Originally Posted by susan cloud

If the thermocouple is defective, could you light the pilot and it and the burner would stay lit? How do you know it is defective? Would the defect be visible? If so, could you tell me
what it would look like?
The heater is 20+ years old. I have never had ONE problem with it, until I had it cleaned.
After the tech cleaned it and I cut it on for the first time, there was NO heat. The pilot
was not lit. The same tech came out, carrying a thermocouple in his hand. He said the
couple was defective and charged me an additional $130. I thought it was somewhat
dubious, so I just wanted to verify some of the things he told me and showed me. I would appreciate any help on this.
Susie

Yes, I was billed for a thermocouple $62 and $69 labor. The reason I had it cleaned was because it was making a "booming" noise when it ignited. I called the local power co and their tech came out and told me I needed to have it cleaned. My house is built on a slab, so the heater is insider. When the HVAC tech was through cleaning it, demonstrated it for me. He lit the pilot and it and the burner came on just fine. However, he did not run it
Through the normal ignition process, he just cut the system on and off about 5 times, in rapid succession, at the thermostat. There was no noise, but I thought that was an odd way of testing an ignition problem. He never mentioned ANY defect on this visit. I did not think it was "good business" to charge me for another service charge when the day after he was there, I cut the system on and it did not work. I believe he may have pulled the
Thermocouple out of the flame in order for the pilot to go out. I only told them I did not
Have any heat, that is why I thought it was unusual for the tech to walk in with a thermocouple in his hand. He lit the pilot when he first came in and it worked, as well as the burner. Does that mean the thermocouple was good?
Feel right about the entire

Some of the older furnaces (Carrier) used thermocouples. And like Northern Heat said if the pilot would stay lit the thermocouple was good. A new thermocouple cost less than ten dollars so are you sure that is what he replaced. If so I feel sorry for you having to pay that much for the part, the labor sounds like it is in the general area of most techs.

[QUOTE=susan cloud]Yes, I was billed for a thermocouple $62 and $69 labor. The reason I had it cleaned was because it was making a "booming" noise when it ignited. I called the local power co and their tech came out and told me I needed to have it cleaned. My house is built on a slab, so the heater is insider. When the HVAC tech was through cleaning it, demonstrated it for me. He lit the pilot and it and the burner came on just fine. However, he did not run it through the normal ignition process, he just cut the system on and off about 5 times, in rapid succession, at the thermostat. There was no noise, but I thought that was an odd way of testing an ignition problem. He never mentioned ANY defect on this visit. I did not think it was "good business" to charge me for another service charge when the day after he was there, I cut the system on and it did not work. I believe he may have pulled the thermocouple out of the flame in order for the pilot to go out. I only told them I did not have any heat, that is why I thought it was unusual for the tech to walk in with a thermocouple in his hand. He lit the pilot when he first came in and it worked, as well as the burner. Does that mean the thermocouple was good? /QUOTE]

[QUOTE=susan cloud]

Quote:

Originally Posted by susan cloud

Yes, I was billed for a thermocouple $62 and $69 labor. The reason I had it cleaned was because it was making a "booming" noise when it ignited. I called the local power co and their tech came out and told me I needed to have it cleaned. My house is built on a slab, so the heater is insider. When the HVAC tech was through cleaning it, demonstrated it for me. He lit the pilot and it and the burner came on just fine. However, he did not run it through the normal ignition process, he just cut the system on and off about 5 times, in rapid succession, at the thermostat. There was no noise, but I thought that was an odd way of testing an ignition problem. He never mentioned ANY defect on this visit. I did not think it was "good business" to charge me for another service charge when the day after he was there, I cut the system on and it did not work. I believe he may have pulled the thermocouple out of the flame in order for the pilot to go out. I only told them I did not have any heat, that is why I thought it was unusual for the tech to walk in with a thermocouple in his hand. He lit the pilot when he first came in and it worked, as well as the burner. Does that mean the thermocouple was good? /QUOTE]

Yes, I am positive I was billed for a thermocouple. At least that is what the invoice reflects
And the tech told me was defective and needed to be replaced. I did some homework on this right after he left on his second visit, because something just did not feel right about the situation. Had he NOT gouged me, I would never have given it another thought, but it looks as though my suspicions were right. The couple was NOT defective, so there was no reason for a second visit, except that he either did NOT light the pilot when he left or fixed it so it would not stay on. You are right, the carrier couple is $15. Nice profit, isn't it?
Thanks so much for your help. I appreciate any information you can offer. Susie