User Interface Troubleshooting Form

This form will aid in determining issues causing communication errors. Please complete every detail of this form. At the end if you still have questions click submit. The completed form will be sent to our Technical Support representatives and you will receive a call during normal business hours. Please stay at the job and give us the opportunity to assist you.

Most communication issues are created by the connecting control wiring, not system parts.

If the UI will let you always check the “Last 10 System Events” to see what is listed there. You may see multiple events on the communicating outdoor unit of low pressure, or outdoor sensor errors. That may indicate a communication problem. Do not rush to change parts that will not correct your problem. Do a reinstall. If you have a communicating outdoor unit that is communicating correctly it will not ask you any questions about that unit during the reinstall.

Do not change any parts until you have connected ABCD from the UI to ABCD on the indoor unit with nothing else connected. If the UI and indoor unit communicate properly then you should be able to go to the outdoor unit or any other connected equipment, disconnect the wires to the ABCD bus, and connect those wires to ABCD on the UI. Then do a reinstall and try to communicate back to the indoor unit without problems. This is testing the wire from the other equipment back to the indoor unit. If you now have problems that wiring should be considered the issue. Try running a temporary wire (down the hall and out a window if necessary), do a reinstall, and test your system. Follow flow chart below.