Yesterday morning, my late 1980's vintage Amana refrigerator started making loud buzzing sounds - 3 seconds long, exactly 90 seconds apart. It seemed to come from the defrost timer, behind the toe panel.
It sounded nasty, so I turned off the fridge, went to work, and took a closer look at it in the afternoon. Turned it back on - the condenser fan blew, the buzzing buzzed, but the compressor didn't come on.
Turned the defrost timer knob to defrost, and the fan and the buzzing both stopped. Turned it back to cool - fan, buzz, no compressor sound.
The buzzing seemed just like when the (ceramic disk) start relay failed a couple of years ago, so I pulled it out, shook it, it didn't rattle, measured 4 ohms across the terminals, and put it back in.
Since the buzzing seemed to come from the defrost timer, I pulled it out, and here are the resistance values ...
TERMINALS....COOL / DEFROST
........3 & 4.....8.4K / Open
........3 & 1.....8.4K / 8.4K
........3 & 2....Open / 8.4K
........2 & 4....Open / Open
........1 & 2....Open / Closed
........1 & 4..Closed / Open
Here are my questions …
#1. The timer is bad. Correct?
#2. Would the timer motor resistance have caused the periodic buzzing, or is there something else going on?
#3. Would the timer motor resistance have prevented the compressor from starting?
#3. My current plan is to jumper the #1 & #3 terminals, to bypass the motor. (See the photo, there’s room for a wire inside the case.) Then I could do a daily defrost manually, until I can get a replacement. (There’s an appliance parts store in the area, but I have an important job to finish that will take another 2 or 3 days, at least.) I’d like to save the food, it’s been 34 hours so far, there’s still a small chance. Also, if a motorless timer will allow the compressor to start, it will prove it’s just the timer, otherwise I’d be spending time and (some) money getting a nonrefundable part, just to find out I’m actually facing a big repair bill, or the cost of a new fridge.
I’m going to hack the timer in the next couple of hours, so if you’re knowledgeable enough to know for a fact that this is a bad idea, please post here soon. Or, if you think it’s a good idea, I’d like to hear about that, too.
Thanks in advance,
George
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