Need HVAC help - thermocouple

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Bob Pl
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Need HVAC help - thermocouple

Post by Bob Pl »

My heater takes 3-5 attempts before it will continue to fire. It's 12 years old. I think the thermocouple is worn out. The heater is made by International Comfort Products Corp installed by Shea Homes 1998. There are two zones (furnaces) in the attic. I have all the manuals tech support/install/user.

The thermal sensor spec. is 300 deg for all the various models covered.

The parts list does not list thermal sensor or thermocouple.

Is there another trade name for it?

Thanks if you can help.

:)
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George Schilling
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Re: Need HVAC help - thermocouple

Post by George Schilling »

It does not have a thermocouple. There probably is a flame sensor that results in a very small amp draw through this circuit when it comes in contact with the flame. If the current isn't strong enough, it won't sense the flame and shuts the gas off. Remove the flame sensor, clean off the carbon build-up, and reinstall it. You should be good to go.
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Bob Pl
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Re: Need HVAC help - thermocouple

Post by Bob Pl »

I will give it a shot. Some brake cleaner should do it & I'll be careful not to drip a puddle anywhere. Don't want to burn down the house.

:)
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Will Kalman
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Re: Need HVAC help - thermocouple

Post by Will Kalman »

Don't use brake cleaner! Look up Phosgene gas, it's beyond scary.

http://www.brewracingframes.com/id75.htm" onclick="window.open(this.href);return false;

EDIT: It looks like you need Argon to produce Phosgene....but still.....
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Bob Pl
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Re: Need HVAC help - thermocouple

Post by Bob Pl »

Thanks Will,

I have seen that, but I will not be within 50 ft of the unit when it fires off. I think it's only an issue when you inhale the gas like a welder might do.

:)
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George Schilling
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Re: Need HVAC help - thermocouple

Post by George Schilling »

Pull the flame sensor out and use emery cloth to clean it.
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Bob Pl
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Re: Need HVAC help - thermocouple

Post by Bob Pl »

George Schilling wrote:Pull the flame sensor out and use emery cloth to clean it.
Will do, thx.
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