On a gas dryer, also turn off the gas valve. Don’t smoke or light a match near the dryer. If you smell gas, turn off the gas-supply valve; call a repairman.
The most common cause of poor drying is a clogged lint filter, exhaust hose, or air vent. Remove lint from the filter after each use. Once a year remove the exhaust hose and shake out lint; insert a straightened section of coat hangar into the outdoor vent to clean the damper and its hinge. Eliminate any sags in the hose that can trap lint or water. Replace a damaged hose with a new type of smooth-wall ducting that is less likely to trap lint.
If your dryer has a pilot light instead of a flameless igniter, read the service manual for instructions on relighting the pilot. With the power off, periodically remove the front-panel grille over the burner assembly, wipe the burner area clean, and vacuum with a crevice tool. If the dryer heats poorly, inspect the flame with the dryer running. A roaring noise or a yellow flame indicates an incorrect air-gas mixture. This, and all other burner problems, should be left to a repairman. If you move from a natural-gas area to a bottled gas area, have the gas company change the burner orifices. If the dryer won’t start Make sure the door is finely shut and the start switch pushed or turned on. Replace a blown fuse or reset a tripped circuit breaker. Electric dryers are usually connected to two fuses or circuit breakers. If one is out, the dryer may run but won’t heat. If the power supply is all right and the dryer still won’t start, call a repairman.
Replacing the drum belt
If the dryer starts but the drum doesn’t turn, the drum belt may be broken. Unplug the dryer and rotate the drum by hand. If it turns very easily, the belt is broken. To replace it, insert a putty knife under the top panel near a front corner. Push the knife against the spring clip holding the top to the cabinet, and raise the top. Unscrew any screws holding the front panel to the cabinet. Note how the wires from the door switch are connected and disconnect them. Lift off the panel. If the operating thermostat is in the front panel, you won’t be able to remove the panel. Set it aside, taking care not to damage the wires. If the drum is supported by the front panel, prop it with a block of wood.
Reach under the drum to locate the idler pulley that controls belt tension. On some dryers, you may first have to remove lower front- or rear-access panels; check your service manual. Push the idler arm away from the pulley and disengage the belt from the drive shaft and pulley. Handle the idler arm carefully; it may be under high tension and could snap back on your hand. Lift the drum slightly and slide off the belt. Slip on a duplicate belt so that its ribbed side is against the drum. Rethread the belt over the idler pulley and drive shaft. Rotate the drum in both directions to make sure that the belt is properly aligned.
Eliminating dryer noises
Remove any objects caught in the drum holes. Tighten the screws on the trim and on the exterior panels. If the noise persists, try to locate its source by opening the dryer door and rotating the drum by hand. If you hear a slow thump that varies with the speed you turn the drum, the drum belt may be worn; replace it. In dryers with sliding drum supports, a scraping sound means the supports are worn. Unscrew the screws holding the supports to the cabinet front; remove and replace the supports.
A worn idler pulley makes a rattle. Many thumps per revolution of the drum indicate a worn drum support roller. To replace these parts you must first remove the top and front panels of the dryer and the drum. Check your service manual or have a repairman to do the job.