Hi. My dryer has quit functioning. Couple days ago I dried a load. Then put in another load, and restarted dryer and walked away. An hour later I checked the dryer and it was off and the load inside was still wet, and the timer showed it had not moved much. So dryer must have quit just after I walked away.
Dryer will not start no matter the location of the timer. Checked the 220V wall breaker and reset just in case, but still no go. Unfortunately this dryer model does not have the drum lamp option, which could help troubleshoot.
Removed back panel and located the schematic. Made following tests (with at least one lead disconnected):
Thermal Fuse - OK (< 1 ohm)
Door Switch - OK (door open - open circuit / door closed - closed circuit)
Push to Start Switch - OK (depressed - closed circuit / not pressed - open circuit)
I temporarily placed a jumper across the thermal fuse and still no go.
No humming noise or any other sound emanates from the dryer when the push to start switch is pressed.
The 4-wire cord from the wall to dryer terminal block appears in good order. OK continuity on each of the four wires and plug is in good shape.
Checked voltage at plug terminal block on dryer:
L1 to Neutral = 105V
L1 to L2 = 210V
So I suspect the issue may be with either the Timer or the Drive Motor.
Thus I removed the Timer to check C-B continuity at different timer positions. Schematic shows C-B should be closed for all timer positions (cycles) except at end-of-cycle. Not sure if I’m testing the timer correctly but with ohmmeter leads each on C and B, I see infinite resistance (open-circuit) at all timer positions including off positions. Does this indicate timer is bad?
Hoping I can ascertain if the issue is or is not with the timer, or something else, before having to pull out the drum to test the drive motor.
Any idea how to best test the timer or what to do next? Thanks for any assist!
Does this indicate timer is bad?
Yes it does.
You can double check this by measuring from B on the timer to Neutral on the line cord.
With the door closed, push the start button. It should drop to a couple ohms (the motor windings).
If OK
Measure from L1 on the line cord to C on the timer, should be 0 ohms.
You can double check this by measuring from B on the timer to Neutral on the line cord. With the door closed, push the start button. It should drop to a couple ohms (the motor windings).
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Meter drops to 3.5 ohms.
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If OK, Measure from L1 on the line cord to C on the timer, should be 0 ohms.
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Meter reads 1.5 ohms (no matter if the ‘push to start button’ and/or ‘door switch’ are activated or not).
Are these two readings expected values?
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If OK then all that is left is the timer.
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Does the above data indicate the timer is the issue? Thanks for your assist.
3.5 ohms.
3.5 seems a little high
The wiring diagram shows the motor windings at 3.6 and 3.8 so it should drop to about 1.8
Did you short the meter leads together before starting reading?
This will tell you if there is a zero offset in the meter.
Was it infinite ohms with no start switch pressed?
1.5 ohms
Also lower than I would expect.
Try it with the timer set to off.
Did you short the meter leads together before starting reading? This will tell you if there is a zero offset in the meter.
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Apologies. Forgot to report zero offset of the digital meter is 0.7 ohms.
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Was it infinite ohms with no start switch pressed?
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Yes.
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1.5 ohms
Also lower than I would expect.
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I’m confused as you had posted should be zero ohms?
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Try it with the timer set to off.
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OK, I re-ran both tests: Timer B - Neutral = 2.4 ohm (1.7 ohms with a 0.7 ohm offset subtracted). Timer C - L1 = 0.7 ohm (Zero ohms with a 0.7 ohm offset subtracted). (same reading if timer was in mid-cycle or an off position). If we on the same page it appears my latest observed readings meet your initial analysis suggesting the timer is bad and needs replaced? Again, your assist is appreciated.
If we on the same page it appears my latest observed readings meet your initial analysis suggesting the timer is bad and needs replaced?
Yes I would replace it, everything else looks normal.