Honeywell Q309A2788 Q309A 2788 Q309A

Ideal part number 175743

A thermocouple is a device that is made of two different metals that produce a small electrical charge when heated on one side.

This small charge activates an electromagnet which opens a valve and allows the gas or water to flow through

The thermocouple detects the heat from the pilot light, and should the pilot light go out accidentally, the thermocouple will automatically shut off the gas valve.

This prevents unburned gas from flooding into the combustion chamber, where a small spark might cause an explosion