Looking for advice on what to look at, how to repair an appliance.
A friend picked up a small wine cooler at a garage sale, for free because it was not running. She figured I might fix it. So I went after it.
Here's what I know so far. This is a ~70W peltier refrigerator. It uses 2, 12V computer-type fans on the hot side of the heat sink and I think just one on the cold side. One of the hot fans has seized - very stiff to turn by hand - and its power lead had lost insulation where it may have rubbed against the edge of the heat sink. I disconnected the bad fan and replaced a 2.5A soldered-on fuse on the controller PCB with a 2.0A fuse I had on hand. When power was reapplied, the internal fan came on briefly but soon the fuse blew again and a puff of smoke rose off the PCB !!!
Unfortunately I was looking inside the unit and was unable to see where the smoke had come from. There is nothing obviously wrong on the board except the blown fuse.
I unsoldered the TEC leads and checked the resistance - I get about 0.8Ω (not a dead short) but my cheap meter is not reliable at such low ohms. When Peltier units fail, do they fail to a short?
Also connected by jumpers to the PCB are the hot and cold fans, an NTC temperature probe, AC power, and an LCD control panel for adjusting the temperature set point.
A friend picked up a small wine cooler at a garage sale, for free because it was not running. She figured I might fix it. So I went after it.
Here's what I know so far. This is a ~70W peltier refrigerator. It uses 2, 12V computer-type fans on the hot side of the heat sink and I think just one on the cold side. One of the hot fans has seized - very stiff to turn by hand - and its power lead had lost insulation where it may have rubbed against the edge of the heat sink. I disconnected the bad fan and replaced a 2.5A soldered-on fuse on the controller PCB with a 2.0A fuse I had on hand. When power was reapplied, the internal fan came on briefly but soon the fuse blew again and a puff of smoke rose off the PCB !!!
Unfortunately I was looking inside the unit and was unable to see where the smoke had come from. There is nothing obviously wrong on the board except the blown fuse.
I unsoldered the TEC leads and checked the resistance - I get about 0.8Ω (not a dead short) but my cheap meter is not reliable at such low ohms. When Peltier units fail, do they fail to a short?
Also connected by jumpers to the PCB are the hot and cold fans, an NTC temperature probe, AC power, and an LCD control panel for adjusting the temperature set point.
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