Furnace Thermal Coupler

This device generates a small electric signal to keep the gas valve open when the pilot is on.

Furnace thermal coupler.

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. 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. Every gas appliance with a standing pilot that cycles on and off needs a thermocouple. Natural gas and propane burn cleaner than fuel oil and most gas furnaces present fewer operational difficulties than oil burners do.

Honeywell home cq100a1039 u cq100a1039 replacement thermocouple for gas furnaces boilers and water heaters 30 inch 4 7 out of 5 stars 80 9 31 9. If it accumulates soot it can give off a faulty reading and shut off the furnace. In fact the problems that affect gas furnaces typically involve the furnace s thermocouple the pilot light or some component of the electrical system. You can test it with a multimeter.

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.