Dryer heating element always on

Dryer Repair
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1

My Maytag MED5770TQ0 dryer started running hot, and when I checked the heating element, I found the metal arm from a pair of my brother’s reading glasses had made it’s way into the element, shorting it. I removed it, and made sure there were no other shorts. I started it up on no heat, and it worked, but when I switched to heat, it threw the breaker. Now it’s back to heat all the time. I replaced the Dryer Cycle Thermostat, with no effect. It heats when set to no heat and during the cool down phase. I’m thinking control board, but I’m concerned I may be missing something that might fry the new board.

3

The control board does not control the heat. You most likely have a grounded heat element. Suggest you replace the heat element.

http://www.appliancepartspros.com/whirlpool-whirlpool-dryer-heating-279838-ap3094254.html

Eric

4

I’ve checked the heating element. I get infinite resistance between the coils and housing, ~10 ohms across the terminals, and ~5-6 ohms from either terminal to the far end of the coil.

I based my conclusion regarding the control board on:
Whirlpool Dryer Always Heating

That said, replacing the heating element is a better, and safer, place to start.

Thanks

5

That’s a totally different dryer than yours. If it’s heating when temp is set to air only, unplug the temp switch. If it still heats, the element is grounding out.

Eric

6

Yeah, realized that after I posted. No heat with temp switch disconnected. Bad temp switch? Would that cause it to heat during cool down ?

7

If it heats during cool down, that’s a faulty timer. If it heats with temp set to air only but no heat with temp switch disconnected, the temp switch is bad. Odd to have two faulty devices like that but the short circuit with the arm from the glasses could have caused a high current through contacts in both devices leading to failure (contacts welded closed).

You can test the timer, should be open between timer BK to R in cool down part of cycle.
Temp switch set to air only should cause open circuit between AH and AH1 on the switch.

Eric

8

Both are closed
I pulled the temp switch to take a look

Anything else to check?

Thanks

9

Well, if it welded those contacts together, it may have done the same to the operating thermostat and high limit thermostat. You can test those on a hot plate. Operating thermostat should open at around 155 degrees and the hi limit at around 221 or 250 depending on which one you have. Should be marked on the thermostat.

Eric

10

Operating tested good, hi limit not. Now, I wait for parts.

Thanks for all your help.