Should I replace t-stats and/or hi-limits and thermal cutouts?
I have a Kenmore model 110.96281100 front load electric dryer. I recently had to replace the heating element because it had burned out. It actually broke the element and was shorting to the cabinet on the L2 side, causing the element to be energized with 120V when the dryer was not running. I also had to replace the element about a year ago due to similiar circumstances. I checked the venting and discovered that I had a 22 foot horizontal run with 4 90 degree bends, equivalent to 42 feet total. I was also dismayed to find that the pipe was the aluminum foil flex that is supposed to only connect from the dryer to the wall. Someone taped together enough of them to get all the way out of the house. I replaced the entire run with 26 ga hard pipe, but could not reduce the number of 90s. This has made a great difference in the performance of the dryer. My question is this: should I think about replacing any of the t-stats or limit safety switches just to be on the safe side? When the element grounded out the last time, the path for the 120v that was energizing the element was not in the path of all the safeties, which would have cut the power. Could the prolonged heat have damaged any of these?
I have tried to explain this as well as I can. I am a HVAC guy and have good electrical skills, but I am not a dryer guy :) Any help would be appreciated.
An expert who has achieved level 2 by getting 100 points
An expert that got 10 achievements.
An expert that got 5 achievements.
An expert that has over 500 points.
Re: Should I replace t-stats and/or hi-limits and thermal...
I have fixed thousands of dryers over the years and the element shorting to ground is a rare ocurance.if you are loosing elements this fast it is due too your ducting as i think you know.and your replacement of the flex with hard ducting will surly aid in that cause.too answer your question,sure the thermo's will have been weakened but i have seen the same thermo's on 15,20 year old dryers ,so they can take some punishment.i owned an appliance repair buissness for ten years and after market wholesale thermo's were about 3$ each so if could find at that kind of price ,ok.other wise may be looking at 30 to 40$ and i dont see it making your dryer much safer then is with out new. God bless,hope that helps,tom
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
While most Samsung dryer component failures will generate a trouble message on the display, a failure of the hi-limit thermal protector won't. If the hi-limit thermal protector has opened, it directly interrupts power to the drum motor. As a result, you can start a cycle using the buttons, the 'brain' will turn on the relays controlling the motor ( the faint clicking sound ) and run the cycle timer, but the motor can't actually run. And without drum rotation being sensed, the burner won't turn on either. Solution is to replace the hi-limit thermal cutout, which is located on the 'nose' of the blower assembly next to the dryer temperature control thermistor ( which is slightly larger than the hi-limit thermal cutout ). Also note that the usual cause of a hi-limit thermal cutout failure ( or a thermistor failure ) is ducts restricted by lint ... both the burner exhaust duct as well as the blower intake duct. Both should be disassembled and thoroughly cleaned while you have the dryer apart.
The cycling thermostat must also be replaced when replacing the thermal fuse. The cycling thermostat's failure to cycle off the heating element results in overheating of the dryer which consequently blows the thermal fuse open.
Replacing only the thermal fuse should the dryer stops running and
fails to start will result in its premature blowing or even the thermal
cut-out (cut-off) located on the heater duct. Like the cycling thermostat, the high-limit thermostat must also be replaced once the thermal cut-out blows open. Refer to the parts diagram in the link below and look for item numbers 31(thermal cut-off), 34(hi-limit thermostat), 39(thermal fuse), and 41(cycling thermostat.
here is a partial list of componets that could cause the dryer to not heat Ignitor control t-stat high limit t-stat gas valve coils thermal cutoff thermal fuse flame sensor electronic control/or timer depending on your exact model cycling t-stat motor
in addation to checking the high limit t-stat have you checked the thermal cut off (the small t-stat) on the heater housing where the element fits into, the high limit t-stat and the thermal cut off BOTH shoud have 0 ohms (the thermal fuse is in the blower housing) the cut off is on the heater box, if you have checked those to be good, check that the heat relay on the control board is closing and sending power to the element, if not replace the control, if all above are good then the motor switch is bad and not sending power to the element(thats a built in safety feature so the dry would never heat when the motor isnt running)the element of course heats only when 240 volts ac is to the element ,120vac from the relay on control through the high limit t-stat then through the thermal cut off finally to the element and 120vac from the motor switch for a comined 240 vac
The first step of the fix has been done by cleaning the lint filter and the vent system.The next step is replacing the thermal cut-off and the high-limit thermostat both located on the blower housing. It is common that the dryer stops heating when the thermal cut-off blows open due to the failure of the high-limit thermostat to cycle off and regulate the heater temperature. The thermal cut-off cuts power to the heating element should the high-limit thermostat fails and the dryer temperature goes extremely high as a safety feature. Click on the links below for the troubleshooting and repair details.
If you bypass the hi limit thermostat you will blow your thermal fuse within minutes. The hi limit thermostat is a bi-metal thermostat which warps when heated to kill power to the element. If its bypassed then the element will not turn off.....which will in turn blow your thermal fuse which is rated at a higher temp than the hi limit. So unfortunately it will not work.
check the thermal fuse if it is blown also change the high limit thermal cut-off fuse www.repairclinic.com shows your parts. go there and enter model number. Also check the heat element. to get into it remove the lint filter and the two screws you'll see there then pry the top up at the front corners. And through the back you should find the heat element and blower housing and thermal fuse and high limit fuse and cycling thermostat.