Robbversion1
New Member
At our home we've been having an on and off issue in regards to our Carrier fan coil and Bryant Multistage Heat pump. It seems like at random times throughout the year, the system would work fine until we start getting the dreaded 178 indoor/179 outdoor communication fault errors.
The wiring is setup with an ABCD setup with 2 data wires and 2 power wires.
Back in Nov 2018 we had a technician come out and replace the Fan Coil board, which I think fixed the issue at the time until it popped back up in Nov 2019. Since we have a hydronic/heat pump setup the heat would not turn on at all from either source. We found if we disconnected the yellow data wire going from the fan coil to the heat pump, the hydronic boiler system would finally take over and start heating. We left it like this for the entire winter not turning on the heat pump once. The spring rolled around and we decided we needed the heat pump to start cooling so we plugged the yellow wire back in. It worked fine for about a month until yesterday where we started getting the fault codes again.
We checked everything from the wiring to the thermostat, fan coil and even the Heat pump. The LEDs on the fan coil and Heat pump all show solid amber lights meaning they're in standby and even the comm light is solid meaning that there is some sort of communication.
Restarted everything a billion times this morning and couldnt get the cooling to kick in.
Now here's the kicker. I can get the system working again, but only if I have the system perform a checkout of the Heat pump - cooling. The heat pump and fan coil turn on and it does its little diagnostic test run. When I stop the test the system cools as it normally would. This is fine until the error pops up again (randomly from what I can tell). So this leads me to believe thats its not fully a communication error like the error code says since I can still control the heat pump with the thermostat.
At this point i'm at wits end trying to figure out what the issue is, so i'm posting here to see if anything has any idea of what is going on.
I know its alot of info that I put into this post, but honestly we spent upwards of $600 getting the system 'repaired' back in 2018 and would like some valuable input before we called in a professional again.
Thanks.
The wiring is setup with an ABCD setup with 2 data wires and 2 power wires.
Back in Nov 2018 we had a technician come out and replace the Fan Coil board, which I think fixed the issue at the time until it popped back up in Nov 2019. Since we have a hydronic/heat pump setup the heat would not turn on at all from either source. We found if we disconnected the yellow data wire going from the fan coil to the heat pump, the hydronic boiler system would finally take over and start heating. We left it like this for the entire winter not turning on the heat pump once. The spring rolled around and we decided we needed the heat pump to start cooling so we plugged the yellow wire back in. It worked fine for about a month until yesterday where we started getting the fault codes again.
We checked everything from the wiring to the thermostat, fan coil and even the Heat pump. The LEDs on the fan coil and Heat pump all show solid amber lights meaning they're in standby and even the comm light is solid meaning that there is some sort of communication.
Restarted everything a billion times this morning and couldnt get the cooling to kick in.
Now here's the kicker. I can get the system working again, but only if I have the system perform a checkout of the Heat pump - cooling. The heat pump and fan coil turn on and it does its little diagnostic test run. When I stop the test the system cools as it normally would. This is fine until the error pops up again (randomly from what I can tell). So this leads me to believe thats its not fully a communication error like the error code says since I can still control the heat pump with the thermostat.
At this point i'm at wits end trying to figure out what the issue is, so i'm posting here to see if anything has any idea of what is going on.
I know its alot of info that I put into this post, but honestly we spent upwards of $600 getting the system 'repaired' back in 2018 and would like some valuable input before we called in a professional again.
Thanks.