Why would a thermocouple need to be replaced if the furnace pilot ignites?

Answer

The thermocouple confirms that the pilot is and stays lit. If the pilot lights but won't stay on, it may be because the thermocouple is bad and telling the unit it isn't lit, thus shutting down the valve.

Updated on March 26, 2018

Original Article:

Troubleshooting Common Furnace Problems With an HVAC Expert
By Dan Robbins
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