Some causes of a dryer not heating are a faulty heating element, high-limit thermostat, cycling thermostat, igniter, radiant flame censor, gas control valve, coil, temperature sensor, timer or thermal fuse. Many of these items can be easily inspected and repaired if someone has the correct tools.
To determine what part is responsible for the dryer not heating, the repairer needs to unplug the dryer and remove its panel so that the parts can be examined. A multimeter can be used to test the heating element, high-limit thermostat, cycling thermostat, coils, radiant flame sensor, temperature sensor and timer. The gas control valve, igniter and thermal fuse must be manually inspected to determine if they are faulty.