Heating, Air Conditioning, Fridge, HVAC/Mars Furnace


QUESTION: Thanks for your guidance so far.  I took your advice and purchase a thermcouple for my Mars Furnace from Home Depot however even though it was considered a universal unit the part that screws into the hole that holds the thermcouple has a ridge that the old one doesn't have and it will not fit into the hole that holds the termocouple.  I have pictures of both parts but don't see anywhere where I can attach a picture.  I wonder if I should just grind down this ridge so the the new part will attach correctly or if there is another way.

First, don't grind the thermocouple.
I don't know exactly what brand your Home Depot's sell, could be a little different where I'm at?
Any way forget the screw in method.
Remove the old thermocouple, Push the new thermocouple up through the hole, push the smallest part that came in the package down over the thermocouple element to hold it in place,
There should be directions to that effect on the back of the package.
The screw isn't used in your case.
The main thing is that the thermocouple stays up in place so that the pilot flame can burn on it's top.

---------- FOLLOW-UP ----------

QUESTION: The problem is the new thermocouple has about a quarter inch ridge at the base so I am unable to push it up through hole. The thermocouple is identical to the other one with the exception of this quarter inch ridge near the base of the thermal couple

I don't know what you have for a pilot/thermocouple set up?
I'm sitting here looking at a thermocouple in a package, it's a Honeywell universal,
The element end is a little less then 3" long, the element itself is a little less then 2" long and about 3/16" thick,
You push the 3/16" end up through the pilot bracket as far as it will go, push the little retainer clip that came with the thermocouple down over the thermocouple element from the top to the bracket to hold the thermocouple in place, the pilot flame when lit should burn onto the top part of the thermocouple element.
If this won't work for you get help.

Heating, Air Conditioning, Fridge, HVAC

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Jim Barnhart


Fifty + years conditioning the air.


Answer questions about , residential and commercial. Answer questions about sheet metal fabrication. Fifty years plus experience. No answers for oil equipment, No answers for kitchen appliances, No answers for laundry appliances, I don't specialize in one particular area of the HVAC area, I'm more of a General Practitioner, Limited in refrigeration/

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