Furnace Thermal Coupler

Honeywell cq100a1013 u not available cq100a1013 24 inch replacement thermocouple for gas furnaces boilers and water heaters quot 4 5 out of 5 stars 191 8 62 8.

Furnace thermal coupler.

This device generates a small electric signal to keep the gas valve open when the pilot is on. You can test it with a multimeter. If the pilot lights but won t stay lit the thermocouple is probably bad. In fact the problems that affect gas furnaces typically involve the furnace s thermocouple the pilot light or some component of the electrical system.

The thermocouple is a safety device located by the pilot light on your furnace. Most gas furnaces use either a flame sensor or a thermocouple often referred to as a thermal coupler both are safety devices that sense the presence of a flame and control the flow of gas to the appliance accordingly. Every gas appliance with a standing pilot that cycles on and off needs a thermocouple. If no flame is present the sensor stops or prevents the flow of gas from the gas valve thus preventing the dangerous situation of gas flowing into the appliance when there.

If it accumulates soot it can give off a faulty reading and shut off the furnace.