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Hello,
So I recently had IAQ stat(9421) + EIM installed. I have an all electric heat pump + air handler (1 cool 2 heat):
Air handler:
Product # FC4BNF036000AEAA
Model # FC4BNF036
HEAT PACKAGE (10KW):
KFAEH2201H10
Heat pump:
Product # 697CNX030000ABAA
Model # 697CN030-B
My heat pump system looks to be similar to the HVAC system described in the post titled "Heat pump not defrosting".
Heating and the stat work ok, but I have noticed that, during defrost, cool air is blown from the registers.
Both "emergency heat" and "aux." heat work ok.
Manually setting stat to "em heat", in which case outdoor unit is off or raising stat's setpoint a few degrees, in which case both het pump and heat strips are on.
Could someone help figure out what could be wrong (may be 1 wire was missed to be wired)?
My condensing unit is not equipped with outdoor thermostat.
What I don't understand is this:
How does the air handler board "know" to activate backup heat during defrost?
On the air handler board, there is W2D terminal (defrost input from outdoor unit).
There is also w2T terminal on the control board - it's used to activate emergency heat or auxiliary heat.
What I don't understand is how does the signal for defrost is processed by the air handler's control board and how should the wiring be set up for it to activate emergency heat during defrost.
From outdoor unit, W1 wire goes up to W2D terminal on the board.
From the EIM, Aux wire goes to w2T on the board.
Should there be another wire from EIM "Aux" terminal to the board w2D?
Thank you!
So I recently had IAQ stat(9421) + EIM installed. I have an all electric heat pump + air handler (1 cool 2 heat):
Air handler:
Product # FC4BNF036000AEAA
Model # FC4BNF036
HEAT PACKAGE (10KW):
KFAEH2201H10
Heat pump:
Product # 697CNX030000ABAA
Model # 697CN030-B
My heat pump system looks to be similar to the HVAC system described in the post titled "Heat pump not defrosting".
Heating and the stat work ok, but I have noticed that, during defrost, cool air is blown from the registers.
Both "emergency heat" and "aux." heat work ok.
Manually setting stat to "em heat", in which case outdoor unit is off or raising stat's setpoint a few degrees, in which case both het pump and heat strips are on.
Could someone help figure out what could be wrong (may be 1 wire was missed to be wired)?
My condensing unit is not equipped with outdoor thermostat.
What I don't understand is this:
How does the air handler board "know" to activate backup heat during defrost?
On the air handler board, there is W2D terminal (defrost input from outdoor unit).
There is also w2T terminal on the control board - it's used to activate emergency heat or auxiliary heat.
What I don't understand is how does the signal for defrost is processed by the air handler's control board and how should the wiring be set up for it to activate emergency heat during defrost.
From outdoor unit, W1 wire goes up to W2D terminal on the board.
From the EIM, Aux wire goes to w2T on the board.
Should there be another wire from EIM "Aux" terminal to the board w2D?
Thank you!
), but if I recall correctly, there's no defrost signal between the indoor and outdoor units, so my indoor unit does not know that the outdoor unit is in defrost mode. The indoor unit knows it's in HEAT mode, but it doesn't know that the outdoor unit has switched to defrost.
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