Roper still not starting changed therm fuse

Hello - Thank you for this wonderful forum, but I still need help.

My dryer stopped working and I replaced the following:

1 of AP3132867 (3392519) - Dryer Thermal Fuse
1 of AP3131939 (3387134) - Dryer cycling thermostat
1 of AP3094244 (279816) - Dryer thermal cut-off kit
1 of AP3131941 (3977767) - Dryer hight-limit thermostat

After this, the dryer still does not start. I will occasionally, start about 5-10 minutes later on its own.

Please help.

Thanks,
Anthony

Here are your parts
Replacement parts for WHIRLPOOL RED4440SQ0 29"ELECTRIC DRYER | AppliancePartsPros.com

See the attachment for the wiring diagram

Of the parts you list only the Dryer Thermal Fuse would effect the starting of the unit. All the others only effect the heating.

Since the unit will actually run it sounds like a timer contact problem.

Unplug the unit and et the timer to mid-scale timed dry.
Now at the line cord measure Neutral to L1.
It should read infinite ohms (open). Now push the start button and it should read a couple ohms (this is the motor windings).
If it still reads open then check the Timer Switch 4 contacts, should be 0 ohms.
I think this is the bad set as the timer seems to advance so the Timer Switch 1 (BU/BK) contacts are probably OK.

If you do not own a meter, I would suggest you purchase a one. You can get a decent digital multimeter for under $20.00. You do not need fancy though it is nice if the leads are a couple feet long.
If it saves ordering one unnecessary part it has paid for itself and you end up owning a useful tool.
Most places will not let you return electrical parts so if you order it, you own it.
A couple things to watch when measuring ohms and continuity

  1. Always remove power from the machine otherwise you could blow your meter.
  2. Always disconnect at least one side of any device you are checking. This eliminates the possibility of measuring an alternate/parallel circuit path.
  3. When checking for closed contacts and continuity use the lowest scale (Usually 200 ohms). Then try higher scales. This scale is 0 to 200 ohms so if the device you are measuring is 300 ohms this scale would show an open circuit which it is not, you are just measuring outside the scale’s dynamic range.

There is a good STICKY at the start of this forum about it’s use.
WED5540.pdf (189.6 KB)

Thank you for the reply - Here is what I found based on your amazingly detailed response.

  1. at L1 - Neutral (breaker off & lines disconnected) 13 kOhms with Timer set to off, mid timer, etc.
    2)L1 - Neutral with START pressed. 1526 Ohms
  2. Timer set to off - BK/BK - open
  3. Timer set to mid timed - BK/BU - 0.1 kOhms - Press start - fluctuates
  4. above with BK/R (timer 4) about the same Ohm readings

I think the timer is bad???

[COLOR=“DarkRed”]I think the timer is bad???[/COLOR]
I am not sure.

[COLOR=“DarkRed”]1) at L1 - Neutral (breaker off & lines disconnected) 13 kOhms with Timer set to off, mid timer, etc.
2)L1 - Neutral with START pressed. 1526 Ohms[/COLOR]
This definitely shows a problem as it should be a couple ohms

[COLOR=“DarkRed”]3) Timer set to off - BK/BK - open[/COLOR] Am assuming BK/BK is a typo.
[COLOR=“DarkRed”]3) Timer set to mid timed - BK/BU - 0.1 kOhms - Press start - fluctuates[/COLOR]
Use a lower meter scale re: 200 ohms so you can see exactly what it is.
Also I do not know why it is fluctuating.

[COLOR=“DarkRed”]4) above with BK/R (timer 4) about the same Ohm readings[/COLOR]
I am not 100% sure what the wire colors are for Timer Switch 4 are but it looks like Tan and White.
I think you may be reading Timer Switch 2 which is in the heater circuit.

Ok - I rechecked the lines:

L1-Neutral - open (when timer set to off)
L1-Neutral - open (when timer set to Mid-dry)

bk/bu - open (when timer set to off)
bk/bu - closed (when timer set mid-dry)

Timer 4 - open (off & mid-dry)

Thanks.

[COLOR=“DarkRed”]Timer 4 - open (off & mid-dry)[/COLOR]
Yes, it looks like the timer is toast.

Timer replaced and all is working well! Thanks

You are welcome

And thanks for getting back to us. Now when others search for a similar problem they will see what actually worked instead of just suggestions about what could be the cause

I seem to be having the same problem but as I am electrically challenged :confused: I am not sure how to do the checks you have listed.
Can you somehow list in laymans terms, I do have a tester.

I am not sure I can explain it simpler.

What have you done if anything so far?

The most common cause of not starting is a blown thermal fuse (Item 7 in Section 3). Unplug the machine and one wire to the fuse and then measure across the fuse with your meter. It should read 0 ohms.
If it is blown (infinite ohms) then be sure to check/clean your vent system as that is the most common cause of it blowing.

If the fuse is OK, I would print out the wiring diagram, I am assuming you have the same unit.
Then with a colored pencil mark in the start circuit.
You can then check the parts involved with the starting of the motor.