How Do I Know if I Have a Continuous Run or Cumulative Run Defrost Timer

• #2

rotate clockwise over time on its own

Whirlpool defrost timers are either Continuous run or Accumulative run. Continuous run means the timer motor is is energized whenever the machine is plugged in. The cam in the timer rotates 360° every 10 hours. Accumulative Run means the timer motor is energized whenever the compressor is running. The cam rotates 360° every 10 hours of compressor run time. Your defrost timer is accumulative run. If your refrigerator is maintaining a good temperature and cycling properly ten hours of compressor run time might take 20 hours.

The defrost timer contacts rest on the cam The cam rotates, opening and closing the defrost contacts and the compressor contacts. To check if the defrost timer motor is getting the correct voltage, measure between the defrost terminal and timer motor terminal.

The replacement timer comes with a flying lead, one side of the timer motor. Push the flying lead over the defrost terminal for your machine.

how hot does that heating element get?

Very! You'll be able to tell if it's on without touching it. There's only three components that make up the defrost system, element, thermostat and timer. When there's a defrost problem, check the element and t-stat for continuity. If they check good replace the timer.

how to gain access to this defrost timer

Remove the top grill and the cover the timer is connected to. I think you only need to remove the screws on one side.

• #4

I never ass ume when it comes to appliance repair. The timer motor should be energized whenever the compressor is on and since it worked once we know it is. It could be a weak timer motor or worn spot on the cam. It sounds like whatever it is, is intermittent.

• #6

No, it should work just fine

• #8

OK, first let's check if that's the right timer. Yours should be accumulative run. Unplug the timer and measure the timer motor resistance across timer motor terminal and the defrost terminal on the timer. You should read a few ohms. Your meter should show 1/open across the common terminal and the timer terminal.

• #10

I was not able to get any resistance readings on either the newly installed timer or old timer.......My meter did show 1/open across the common terminal and the timer terminal (1&3).

Set your meter on a higher ohms scale like 1K or 10K. There's a timer motor in there and it's connected to the timer motor terminal and either the common terminal for continuous run or the defrost terminal for cumulative run. If you can't find the timer motor the timer might be bad.

I'm not sure about the accumulative run and there was no flying lead found on the old timer

The original timer and the replacement timer won't have the flying lead. They are set up at the factory as cumulative run. Whirlpool developed the replacement timer with the flying lead to take the place of both the continuous run timer and the cumulative run timer by connecting the flying lead to common or defrost. Whichever one you need.

This is the exact same diagram on your schematic. I took out some of the wires that weren't necessary to make it easier to explain. Your schematic shows the defrost timer, the four numbered terminals and contacts inside the timer and the timer motor. One side of the timer motor is connected to terminal #3, timer motor terminal. The other side of the timer motor is connected to the #2, defrost terminal.

The timer motor is 120 VAC so it doesn't matter which side of the timer motor is + or which side is -, it's always going to run the same direction. Remember, cumulative run timers only energize the timer motor when the compressor is running. L1, power cord black wire, connects to the #1 common terminal. When the compressor is running the contacts between #1 and #4 are closed so the current path is into the timer at the common terminal (#1) and out the compressor terminal, (#4) to the cold control. When the cold control is calling for cooling the contacts in the cold control are closed and L1 comes out of the cold control (red wire) and goes to the condensor fan motor, the compressor, and the timer motor terminal (#3) on the defrost timer. Now the #3 terminal is the L1 (+) side of the timer motor. If you understand that current takes the path of least resistance, the contacts between 1 and 2 are open and the defrost heater is not energized so the defrost heater is used like a wire and becomes the path for the neutral side to the #2 terminal. Now the timer motor has 120 VAC and rotates. When the cold control cycles off the timer motor loses L1 and the motor stops.

When the timer goes into defrost the contacts close between 1 and 2. Now the #2 terminal becomes the L1 (+) side of the timer motor and the #3 terminal becomes the neutral (-) side of the motor thru the condensor fan motor. When the fan is not energized it becomes a current path. Out of the timer #3 red wire into the fan motor thru the fan motor and out the white wire to the neutral side of the power cord. According to your wiring diagram you should read the timer motor across #2 and #3

How confused are you? I can keep going. LOL

• #12

it does not offer a 1K or 10 K setting.

K=1000 Some meters mark the scale 1000 or 1K others use 2000 or 2K. It's the same ohm range.

evaporator fan motor. Is that motor also 120 VAC,

Yes, AC stands for Alternating Current, 60 cycle means the current alternates between +120V to -120V 60 times a second. On any AC device you have +- on one side and +- on the other side If you switched the wires you would have the same thing.

And with that information, my friend, School Is Out!. I don't have the time to teach refrigeration repair 101. Especially for free...LOL I'll help you fix your defrost problem. You should have all the information you need to fix the defrost problem now. If you run into a problem and have a question, just ask.

blackdaris1964.blogspot.com

Source: https://www.applianceblog.com/mainforums/threads/kitchenaid-built-in-refrigerator-ksss42qdw05-defrost-timer-rotation-question.88148/

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