Does your clothes dryer work just fine when you first throw a load of laundry in but stop heating after a period of time? Are you tired of listening to its tumbler rotate and blow only to open its door and find a cold, wet stack of garments? Before you rush out and buy a new dryer that doesn't quit halfway through its job, you should know that it, too, will likely succumb to this problem shortly after you get it up and running. Why? Because the dryer you have right now probably isn't broken at all; it's just equipped with a hi-limit thermostat to protect you from the risk of fire.
The Stats On Dryer Fires
The period between 2006 and 2010 was a rough time for washer and dryer manufacturers. During these years, washers and dryers were determined to be the cause of 16,800 fires. Dryers were the by far the biggest culprits, though, accounting for 92 percent of the devastation. In an effort to lower these numbers, dryer manufacturers began equipping their products with hi-limit thermostats.
Enter Hi-Limit Thermostats
The hi-limit thermostat on your clothes dryer can be found on the housing or cage assembly of the heating element. The thermostat has a little pole on it that naturally sits closed, thus allowing electricity to flow from the circuit to the heating element. When the temperatures inside the drum of your dryer get extremely hot, though, the heat forces that pole upwards, thus breaking the flow of electricity and shutting off power to the heating element. While the temperature that triggers the thermostat to shut off the power varies by manufacturer and model, it's generally around 250 degrees Fahrenheit.
It should be noted that thermostat controls the power to the heating element alone—not the whole dryer. If the hi-limit thermostat on your dryer is tripped, the machine will continue to rotate and blow, but it will produce any heat while doing so.
Why Your Dryer's Hi-Limit Thermostat Is Being Triggered
So why, exactly, is your dryer getting so hot that it's tripping the hi-limit thermostat? Because it's not getting cleaned well enough. Most people know to empty the lint trap out after each use, but not everybody knows that their dryers' exhaust duct and vent should be cleaned regularly, too.
All the little fiber particles that your dryer's lint catcher doesn't catch are filtered out through the duct and vent. Over time, the particles can stick and build up on the walls of the duct. As the buildup worsens, airflow is restricted and your dryer becomes prone to overheating.
Cleaning Your Dryer's Duct And Vent
Fortunately, there's an easy fix for a dryer that keeps going cold due to duct and vent residue. Simply pull your dryer away from the wall and locate the point at which the duct connects to the dryer. Detach the duct from the dryer, and use a vacuum cleaner wand attachment to suck out any visible debris.
Next, either run your vacuum cord through a window or attach an extension cord to it to give yourself more reach, and make your way outside to find your dryer vent. Remove the vent from its casing to expose the opposite end of your dryer duct, and vacuum that out with a wand attachment, too. Replace the vent cover and reattach the duct to the back of the dryer and you should be good to go.
For dryers with exceptionally long ducts or rigid metal ducts, a standard vacuum cleaner attachment won't work. In these instances, you'll need to recruit the help of an appliance repair service; companies like Affordable Appliance Repair will have special tools that allow for a longer vacuuming reach and more flexibility.
If your dryer works fine when you first start drying a load of laundry but stops heating up after some use, it's likely not broken—it just needs its duct and vent cleaned. Either do the job yourself or have a professional take care of it, and then continue to do it about twice a year. Doing so will not only fix your problem, but it will also prevent it from occurring again in the future.