Rank: Member
Groups: Registered
Joined: 7/30/2015(UTC)
Posts: 2
|
Whirlpool dryer will not regulate heat. It has 5 settings for temperature: no heat, and 4 levels of heat from low to high. It basically will either be OFF or ON--there is no difference in the 4 levels of heat.
I have already found and replaced several items that were bad. Thermal fuse, thermistor, cutoff, thermostat--all temperature sensors new. I also found a short on the heating element and repaired that. Verified air flow is unobstructed.
I hate to buy a new dryer for something that should be straightforward to fix, but at this point, how it controls temperature is a black box. What parts should I check / replace to fix the unregulated heating?
THANKS FOR THE HELP!
Chris
|
|
|
|
|
|
Rank: Advanced Member
Groups: Expert
Joined: 10/16/2012(UTC)
Posts: 3,806
Was thanked: 7 time(s) in 7 post(s)
|
Wow, all those components were bad? If the thermal fuse was bad, the dryer would not run at all. There is no thermistor in this dryer. How did you "fix" the grounded heat element? A grounded element would cause the problem you are having of lack of heat level control. You replaced the operating thermostat? That's the one on the blower housing that has 4 terminals on it. The way the different heat levels work is that different power levels are applied to the heater in the operating thermostat. The two violet wires on the operating thermostat connect to it's internal heater. The thermostats internal heater "tricks" the thermostat into sensing that the dryer is hotter than it actually is so that thermostat will open early causing the dryer temperature to be lower. If the dryers main heat element is grounded, it will produce heat regardless of the temperature switch setting.
Eric
|
|
|
|
|
|
Rank: Member
Groups: Registered
Joined: 7/30/2015(UTC)
Posts: 2
|
I think what started this cascade was the heating element grounding out causing it to overheat all the time. The thermal fuse and the sensor above the heating element were both bad. Thermal fuse kept motor from running. When I changed the thermal fuse, I also replaced the operating thermostat. So I believe that part is good. The other sensors I replaced were both on the heating element side and not sure if their names. One is directly in line with heater element and the other one is above the heater element. Does that help?
Is there some controller that regulates the heat / current delivered to the operating thermostat? Is that in the small board assembly? Or maybe in one of the switches?
Thanks again!
Chris
|
|
|
|
|
|
Rank: Advanced Member
Groups: Expert
Joined: 10/16/2012(UTC)
Posts: 3,806
Was thanked: 7 time(s) in 7 post(s)
|
The operating thermostat is what regulates the heat. In high heat setting, that thermostat opens when temp is 155 degrees and then closes again when it drops to 130 degrees. The heat element is simply turned on and off repeatedly to obtain the correct overall temperature. When other than high heat is selected, an internal heater inside the operating thermostat is used to force the thermostat to cycle and cause a lower overall dryer temperature. The control board is just used to advance the timer when timer is used in the auto dry cycles. You would need to check the actual air temperature at the dryer exhaust to determine if everything is working correctly.
Eric
|
|
|
|
|
|
Forum Jump
You can post new topics in this forum.
You can reply to topics in this forum.
You can delete your posts in this forum.
You can edit your posts in this forum.
You cannot create polls in this forum.
You can vote in polls in this forum.
Important Information:
The AppliancePartsPros.com uses cookies. By continuing to browse this site, you are agreeing to our use of cookies.
More Details
Close
