Kenmore AC model 73089 (Plasmaire) keeps blowing control board

[starrigger]

I've replaced the control board in this AC unit twice in the last two summers, and it just blew again.  Runs great otherwise--we keep the unit because it's so quiet and well designed aside from this little problem. 

The first time, in 2009, a tech replaced the board for me. When it blew again this July, I replaced it myself.  Last night, it died again.  (Meaning, no apparent power to the machine at all, though the cord and outlet are fine.)  Each time, it was after a period of prolonged use, though last night it quit during the night when things were cooler. 

The board has a fuse on it, but I checked continuity on the fuse from the last one I took out, and it seems okay.  Something else is going.  Can I reasonably ask Sears for a warranty exchange on this board? 

[appl.tech.29501]

Does this board look the same as yours?

You can try taking it back, most places don't like to give refunds on electric parts.

Can you see any signs on the other boards of a problem area...burn marks, etc.?

[starrigger]

[user=27301]appl.tech.29501[/user] wrote:

Does this board look the same as yours?

You can try taking it back, most places don't like to give refunds on electric parts.

Can you see any signs on the other boards of a problem area...burn marks, etc.?

That looks like the board.  I called Sears parts to ask about a replacement, and they wanted me to schedule a repair visit. 

No sign of any damage on the board.  It looks like new, and the fuse is good.

There's a big capacitor that sits next to the board.  Nothing visible on it, either--but could it be surging and blowing something? 

[RegUS_PatOff]

may be similar to

LG   LW1500 Service Maunal

Troubleshooting starting on PDF page 30

and could do some voltage tests on the Controller (power supply) output

bottom half of PDF page 23

[starrigger]

[user=3641]RegUS_PatOff[/user] wrote:

may be similar to

LG   LW1500 Service Maunal

Troubleshooting starting on PDF page 30

and could do some voltage tests on the Controller (power supply) output

bottom half of PDF page 23

I downloaded the manual, but page 23 is blank.

I did find a page on troubleshooting electrical parts.  It involves testing the voltage on a lot of components that I guess are on the control board, and seemingly would have to be done with it in place and power on.  That's pushing my limits as an amateur, esp. since these instructions are for another unit that might be the same, or might not be. 

Also, wouldn't that show me what's gone bad, but not what caused it to go bad? 

[RegUS_PatOff]

[user=33006]starrigger[/user] wrote:

I downloaded the manual, but page 23 is blank. 

these instructions are for another unit that might be the same, or might not be. 

Also, wouldn't that show me what's gone bad, but not what caused it to go bad? 

are you using Adobe Reader ?

this model uses the same Control Board

once you find out what part went bad, it may be determined what caused it.

[starrigger]

    [user=3641]RegUS_PatOff[/user] wrote:

[user=33006]starrigger[/user] wrote:

I downloaded the manual, but page 23 is blank. 

these instructions are for another unit that might be the same, or might not be. 

Also, wouldn't that show me what's gone bad, but not what caused it to go bad? 

are you using Adobe Reader ?

this model uses the same Control Board

once you find out what part went bad, it may be determined what caused it. 

Yes, using Adobe Reader. 

I printed p. 31, which describes voltage tests on--I think--the control board.  (It doesn't really say.)  I don't think I have enough knowledge of how to use a voltmeter to do those tests.  Continuity I can do.  Voltage across two points I can clearly see and identify, I can do.  But I don't even know what parts they're talking about in those instructions, much less how to measure it. 

I was sort of hoping someone might be able to say, "Oh yeah, the frazzinator on those things goes bad, and that's why the control boards blow."  Or maybe, "If you unplug the board, turn around three times, and plug it back in, you'll be all set." 

Hope springs eternal. 

[RegUS_PatOff]

[starrigger]

I appreciate your posting that. But I haven't a clue what to do with it.

Let me ask this way: Have you (or has anyone here) dealt with this particular problem on this board? If so, have you seen any pattern of likely causes?

[RegUS_PatOff]

not me ..

could be a power company line problem