toxcrusadr
Omelette au Fromage
I have a nice 2010 Kenmore that powers up, fan runs but the compressor does not come on. Maybe you guys could follow my train of thought.
It has two boards, one under the control panel and one inside. The control panel board has the buttons to adjust fan, humidity etc. and the humidity sensor is connected to it. The main board has the relays for turning on the compressor and fan. Also has a transformer for power, and a typical 4 diode rectifier, caps and 5V and 12V voltage regulators. I don't have a schematic but likely the 5V is fed to the control panel board which is working fine, and the 12V feeds the relays on the main board.
Now, the fan comes on as though the machine wants to run, so I figure the humidity sensor is working and the control board is sending signals to the main board to turn on the fan and compressor, but the compressor isn't coming on. Either it's broken, not getting the message, or has a bad start or run cap.
There is a 40 uf cap next to the board that measures 39.8 uf so I think that's OK. This is probably a run cap due to the 40 uf rating (start caps are higher).
I checked for voltage at the compressor, nothing.
There was 120VAC on one side of the compressor relay but not on the other side. This confirms it is not switching.
I briefly jumpered across the relay and the compressor motor began to start up.
Here is where I start to bog down on troubleshooting. This board has, in addition to the two 3-pin voltage regulators and rectifier diodes: 3 small can caps, 3 small transistors each with a diode, two rectangular stacked film caps, one big relay for the compressor and two smaller ones (probably for two fan speeds), a Zener diode and a couple resistors. I'm not sure how the actual control circuit works.
Should I...
1) Try to figure out whether the compressor relay is getting a turn-on signal and if not, why not
2) Replace the compressor relay ($5)
3) Replace the entire board ($35 from Sears)
Any ideas? I feel like I'm tantalizingly close to fixing a $200+ appliance here.
It has two boards, one under the control panel and one inside. The control panel board has the buttons to adjust fan, humidity etc. and the humidity sensor is connected to it. The main board has the relays for turning on the compressor and fan. Also has a transformer for power, and a typical 4 diode rectifier, caps and 5V and 12V voltage regulators. I don't have a schematic but likely the 5V is fed to the control panel board which is working fine, and the 12V feeds the relays on the main board.
Now, the fan comes on as though the machine wants to run, so I figure the humidity sensor is working and the control board is sending signals to the main board to turn on the fan and compressor, but the compressor isn't coming on. Either it's broken, not getting the message, or has a bad start or run cap.
There is a 40 uf cap next to the board that measures 39.8 uf so I think that's OK. This is probably a run cap due to the 40 uf rating (start caps are higher).
I checked for voltage at the compressor, nothing.
There was 120VAC on one side of the compressor relay but not on the other side. This confirms it is not switching.
I briefly jumpered across the relay and the compressor motor began to start up.
Here is where I start to bog down on troubleshooting. This board has, in addition to the two 3-pin voltage regulators and rectifier diodes: 3 small can caps, 3 small transistors each with a diode, two rectangular stacked film caps, one big relay for the compressor and two smaller ones (probably for two fan speeds), a Zener diode and a couple resistors. I'm not sure how the actual control circuit works.
Should I...
1) Try to figure out whether the compressor relay is getting a turn-on signal and if not, why not
2) Replace the compressor relay ($5)
3) Replace the entire board ($35 from Sears)
Any ideas? I feel like I'm tantalizingly close to fixing a $200+ appliance here.