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Old 07-14-2010, 09:24 AM   #16
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i'm gonna provide my non-professional two cents. you smelled burning electronics, right? i had the same problem on my furnace a couple years back. the control board is screwed down and you can't see the underside of it. take plenty of pictures first so you know where all the wires go, then unscrew it and flip it over. look for any burnt out solder joints. it may be as simple as re-soldering one or a couple. if it's a resistor or some electronic component on the board itself, that may be a little more complicated. i fixed mine for free that way, otherwise a new board is probably $150 or so, ballpark area.

with regards to homeowner's insurance, it all depends on how much stuff got fried. most of the time the deductible is higher than the cost of fixing everything, so it's only useful for major stuff like a tree through your roof.


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Old 07-14-2010, 06:13 PM   #17
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fixed it

It was the transformer. That was all. I did it myself.

No "pros" or fear needed. Just good old DIY.
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Old 07-15-2010, 08:24 AM   #18
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Originally Posted by jtwestn View Post
It was the transformer. That was all. I did it myself.
If a destructive current passed through the transformer, then where did it continue on through? It did not destroy a transformer and stop. Surges are currents that flow simultaneously everywhere in a path from cloud to earth. If that current was through the transformer, then where did it continue to obtain a connection to earth?

Overstress is a failure that occur months after the initial damage. Other parts in that path may have been overstressed.

Meanwhile, you had failure because you permitted energy to find earth destructively inside the building. You got lucky. This event may have been a warning that you did not have sufficient earthing and a 'whole house' protector. A protector that sells for about $1 per protected appliance.

Protection is always about where energy dissipates. Either a direct lightning strike is absorbed harmlessly outside the building. Or that energy is inside hunting for earth destructively via appliances. You suffered the latter. A complete solution means the next surge causes no damage. But only if you learn from this event to earth a well proven, inexpensive, and effective solution.
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Old 07-15-2010, 11:28 AM   #19
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If you have a condensation pump that's on a GFI, be sure the GFI didn't trip and just cause your condensate tank to fill up. Been there myself.
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Old 07-15-2010, 05:43 PM   #20
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Whenever a furnace gets water damaged or a power surge ALL the safety controls should be properly checked, unless you don't like "safety".
"Cut it twice and it is still too short".
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Old 07-15-2010, 07:58 PM   #21
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I haven't read the replies but here is my take; First off, I'm sorry buy Godman is not my brand of choice and I don't mean that in a bad way (it WAS running fine.

1) Go to thermostat, turn to fan on - If fan turns on stay out of the attic/basement - airhandler , all is well with your 24V low voltage circuit. If the fan does not come on, you could have fried the board, fuse or lost 230V to unit. Easy to check with a voltmeter or at breaker box. If power goes in the airhandler, the fuse is good but the indoor fan won't come on, it's one of those problems. I've even seen a bad thermostat but thats easy. Green and Yellow go to the airhandler with 24V ac from the stat.....

2) If the fan runs, drop the temperature to 50 degrees or way down, now you are calling for cooling. Go outside, whats it doing? nothing? If you have a disconnect that you remove, flip over to turn it off and push back in, there are 2 fuses behind that cover.
Check those fuses........

If you have a knife disconnect, it may or may not have 2 fuses or just rely on 230V at the condensor; Use the voltmeter.

If you have 230V now open the cover on the condensor; You usually kloosen 2 top bolts and remove 2 lower and a half cover slides out but they are all diff. Just take the cover off where the wires enter. The small wires should have 24V AC and pull in one line (L1) on your contactor, the other side (L2) is directly wired and always live. This is where you usually find that the contactor got fried or the run cap exploded and the contacts arced off.

It's all easy, you had a surge. I did one a week ago and he needed a contactor and capacitor (which runs the compressor and condensor in parallel) and the wires were fried.

Always take notes, draw diagrams, shut power off and just THINK. Personally if everything is intact and I have 230V, I just push the contactor in with a screwdriver and see if the unit starts. Then I know whether I have a bad contactor and or low voltage 24V av issue; Or if it does nothing, I have a 230V high voltage issue........

GOOD LUCK - Piece of Cake!!


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