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Hey All, new to the forum and HVAC in general, so I wanted to see if anyone could help.
Recently got cold in my neck of the woods, and when I turned on the heat it was just blowing cold air. I have a heat pump system in my house with 2 zones. Last year the same thing happened and was told the capacitor on the outdoor unit was the culprit, this year it was diagnosed as the zone control board (Honeywell HZ221). After chatting with the technician, mentioned upgrading to an HZ432, among other things. Really nice guy, gave me the quote and said they can do it, but not really difficult to do myself. He left with me with a bypass from my downstairs thermostat directly to the equipment, which has been working as it should.
Fast forward to today, HZ432 gets in, I start by mounting the new board and start moving wires over from the old one, including the ones he tied together to bypass the board. Seems pretty straightforward until I get to the equipment terminal block. The old unit had a "C" terminal, which I assumed was for the common wire, but the new one does not. This blue wire goes directly to the outdoor unit, which looks like it goes to the common terminal on the defrost board. In any case, I'm back at square one, where the outdoor unit does not come on as it's supposed to when I call for heat only, so what ends up happening is the blower in the air handler (attic unit) will turn on, but it will blow air between 50 and 60 degrees only.
So, the question is where does that "C" wire fit into this and should it be causing this issue? I would think that it wouldn't but maybe leaving it floating is causing the 24V signal to not make other components run as they should. I appreciate any suggestions, otherwise I'll just return the board and have the HVAC company do it as a last resort. I'm attaching pics of the zone board w/ extra wire, the wiring coming into the outdoor unit, connection at the control board and then a generic pic of the board showing the "C" terminal.
Recently got cold in my neck of the woods, and when I turned on the heat it was just blowing cold air. I have a heat pump system in my house with 2 zones. Last year the same thing happened and was told the capacitor on the outdoor unit was the culprit, this year it was diagnosed as the zone control board (Honeywell HZ221). After chatting with the technician, mentioned upgrading to an HZ432, among other things. Really nice guy, gave me the quote and said they can do it, but not really difficult to do myself. He left with me with a bypass from my downstairs thermostat directly to the equipment, which has been working as it should.
Fast forward to today, HZ432 gets in, I start by mounting the new board and start moving wires over from the old one, including the ones he tied together to bypass the board. Seems pretty straightforward until I get to the equipment terminal block. The old unit had a "C" terminal, which I assumed was for the common wire, but the new one does not. This blue wire goes directly to the outdoor unit, which looks like it goes to the common terminal on the defrost board. In any case, I'm back at square one, where the outdoor unit does not come on as it's supposed to when I call for heat only, so what ends up happening is the blower in the air handler (attic unit) will turn on, but it will blow air between 50 and 60 degrees only.
So, the question is where does that "C" wire fit into this and should it be causing this issue? I would think that it wouldn't but maybe leaving it floating is causing the 24V signal to not make other components run as they should. I appreciate any suggestions, otherwise I'll just return the board and have the HVAC company do it as a last resort. I'm attaching pics of the zone board w/ extra wire, the wiring coming into the outdoor unit, connection at the control board and then a generic pic of the board showing the "C" terminal.