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Replacement parts for ADMIRAL ASD2120DRW REF - SXS/I&W | AppliancePartsPros.com

Defrost timer is Item 13 in Section 2.

There is often a hole in the cover/mount to let you rotate the timer cam without disassembling everything.

OK, let it run for a while so there is frost on the coils again.

First remove the evaporator cover in the freezer so you can see the coils.
Do not let them de-ice.
If they are heavily iced/frosted over you have a defrost problem.

If yes.
Manually force a defrost cycle by turning the defrost timer cam (Item 13 in Section 2) till the fans and compressor turn off.
Now check the defrost heater to see if it is on.
Be careful you do not want to burn your fingers.
If the heater is on then the timer needs replacing, re: it is probably stalling during it's rotation so is never getting into a defrost cycle.

If not on.
Unplug the unit. Unplug the heater/defrost thermostat combo (Item 12 in Section 4) from the wiring and measure it for continuity, usually around 20 ohms or so.

Note that the defrost thermostat opens just above freezing so must be frozen to check it. Also inspect it, if it is bulged at all replace it even if it measures OK.

If both the above are OK then odds are the defrost timer contacts are toast or the timer motor is not advancing it into defrost..
Best way to test this is a live test to see if you have 120 volts across the heater/defrost thermostat combo.
For the timer motor you can mark the timer cam and a lined up mark on the cover. Let it run for a couple hours if the marks still line up the timer is not advancing.

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.

Here is my update, Denman. The coils are heavily iced/frosted again. I did manually force a defrost cycle by turning the defrost timer cam 'till the fans and compressor turns off and waited about 15 minutes but the defrost heater did not come on. I unplugged the unit and unplugged the heater/defrost thermostat combo from the wiring and measure it for continuity, but I did not get any resistances on my multi meter. So, I would assume that the defrost heater is not functioning. Kindly suggest.

Thank you. I will order the mentioned part and update you once I have it installed. I found this forum very expedient.

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.