***Gas Valve Solenoid***
Gas dryers have two or more gas valve solenoid coils. The gas valve solenoids open the gas valve ports to allow gas to flow into the burner assembly. If a gas valve solenoid fails, the dryer won’t heat. To determine if one or more of the gas valve solenoids has failed, check the igniter. If the igniter glows and goes out but does not ignite the gas, the gas valve solenoid is defective. If one or more of the gas valve coils are defective, I recommend that you replace them as a set.
***Igniter***
The igniter uses heat to ignite the gas in the burner assembly. If the igniter is not working, the gas will not ignite, preventing the dryer from heating. To determine if the igniter has burned out, use a multimeter to test the igniter for continuity. If the igniter does not have continuity, replace it.
***Flame Sensor***
On a gas dryer, the flame sensor detects the heat emitted by the flame. If the flame sensor isn’t working, the dryer won’t heat. Before checking the flame sensor, first make sure that the igniter and thermal fuse are not at fault. To determine if the flame sensor is defective, use a multimeter to test the sensor for continuity at room temperature. If the flame sensor does not have continuity at room temperature, replace it.