Gas clothes dryers are relatively simple machines and will usually last for years. While they use gas as a heat source, they use electricity for all their operations so troubleshooting one that isn't working will likely involve working with electricity. All dryers have an electric motor powering a drive belt which in turn rotates the drum filled with damp clothes.
Air is forced past the gas flame by a blower, where it's heated then directed into the drum. In the drum, the hot air removes moisture along with some lint from the clothes, then vents out through a lint screen, and finally out an exhaust duct. Dryers also have a timer, sensors, and controls that monitor the temperature and moisture inside the dryer and regulate its operation. All these mechanical and electronic components need to be working properly for your dryer to operate. Here are some common symptoms and possible diagnoses when dealing with your gas dryer.
1. No Power
If your dryer won't go at all, first check if the dryer cord is plugged firmly into the outlet, is in good repair, and that no fuses or circuit breakers are burned out or open in the fuse box.
Another potential cause for not working is the door switch on the dryer door. A dryer won't operate if the door switch is faulty. Since the dryer won't run if the sensor is faulty or the door doesn't close properly, you will need to test parts and replace those that are not working.
2. Clothes Don’t Dry
If the dryer turns on and appears to heat but your clothes just don't get dry, your problem could be a blocked lint screen or exhaust duct. Clean the lint trap and clean out or even unkink the exhaust duct. Another potential cause for slow drying might be that you're drying too many clothes at once — drying smaller loads may fix your problem.
3. Drum Doesn’t Turn
If the dryer motor runs but the drum won't turn, your problem is quite likely a broken drive belt. Drive belts are relatively easy to replace but you do need to open the dryer up to remove and replace the old belt since the belt goes right around the dryer drum.
4. No Heat
If your dryer drum turns but there's no heat, it's most likely related to the gas heat source itself. Most gas dryers have fuses and circuit breakers in the electric system that turns the gas flow on and off. If any of them aren't working the dryer won't run, so the fix is to test and replace any fuses or breakers that test bad and aren't working.
There are also thermal fuses that measure the heat in the exhaust duct and will shut the dryer off if the exhaust temperature gets too hot. A burned out thermal fuse will prevent a dryer from working, so replacing a defective thermal fuse will get your dryer going again.
Finally, the gas heating element in your dryer may be burned out. You can test this electronic component (glow plug) for continuity using your multimeter, but replacing it is usually best left to a professionally qualified gas repairman.
Warning: Before testing any components of your dryer unplug your dryer or shut off the power at the fuse box. Never work on a dryer that is plugged in. Also never attempt to move a gas dryer with the gas line turned on. Always turn off the gas and disconnect the pipe before attempting to work on a gas dryer.
Your owner’s manual is a great place to start troubleshooting. Most will give you potential causes for your dryer's problem as well as providing dryer part and component numbers and outline how to order replacement parts.