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Old 07-17-2020, 10:19 AM   #1
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HVAC not working


Hoping to get some advice. I'm a long time poster/member of this forum so I'm not totally inexperienced with HVAC. Hope somebody had a suggestion for something I haven't thought of.

So a friend of mine is on vacation and we're checking on his house daily and today my wife noticed it was very warm... it's been cool all week. Wife checked the t-stat and it showed 80 degrees indoor temp. Many hours later when I went to check on it, indeed the house was at 80 degrees with a 70 set point on the TStat.

It's an *old* system. Trane air handler with a lennox outdoor, R-22 condenser. Appears to be a heat pump.

When I showed up, there was a lot of condensate on the floor. The condensate line was draining a bit into the drain but clearly condensate either overflowing the drain pan or it's cracked etc... internally. I found some puddled water inside the upper compartment of the air handler and the suction line was cool to the touch and had condensate on it. So clearly it was running at some point earlier in the day.

The system was totally dead. The fan was in the "on" position at the Tstat but wasn't running. I measured voltage at the Y1/Y2 terminal- so it was calling for cool. The condenser unit wasn't running. The fan/G terminal also showed ~24 VAC.

The board, which seems to have been replaced at some point, shows a green and steady red light illuminated. The red light was steady but I did notice it would go out and turn back on after a few minutes. Wasn't "blinking" out any codes or anything.

It's an old system and doesn't seem to have anything "fancy" about it. No
"communicating" tstat or condensate pump etc...

Here is a pic of the control board. With the steady red light (with an occasional "cycle" every few *minutes* of going off then on). Green light always stays on.

I tried resetting everything pulling power from the indoor and outdoor unit....nothing.

My current theory is the coil froze up and the condensate dripped down into the control board and fried it (not entirely convinced of it).

I found it strange the suction line could still be cool to the touch and wet with condensate when I arrived many hours later after my wife initially reported the warm indoor temp.

Given that state of the control board... any suggestions to check before they call out a tech (from vacation :-) )?
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Old 07-17-2020, 11:10 AM   #2
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Re: HVAC not working

May have a overflow switch somewhere. Is the condenser calling to run?
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Old 07-17-2020, 02:10 PM   #3
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Re: HVAC not working

Post the pic of the board again as I don't see it. Or a video of it. Also the model # of the outdoor unit and serial # helps.
"Cut it twice and it is still too short".
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