Configure TH8320U for Add-On Heat Pump

Honeywell Thermostat: TH8320U

Re: ADD-ON HEAT PUMP

The TH8320U VisionPro thermostat is capable of direct-control of an add-on heat pump system. (Does not apply to York units with Yorkguard Module)

Requirements:

• TH8320U Thermostat
• C7089U Outdoor Sensor
• Minimum #8 (preferably #10) stat wire between Heat Pump & Furnace
• Minimum #8 (preferably #10) stat wire between Furnace & Thermostat

CONFIGURE THERMOSTAT:

• Enter "Installer Setup".
• Modify the items in the chart below.
• Press "Done" to exit "Installer Setup" and save changes.

WIRING:

SEQUENCE OF OPERATION:

Cooling Mode 

• Thermostat energizes "O" whenever the mode is "Cool'
• Thermostat energizes "Y' and "G" when there is a demand for cooling.

Heating Mode

• When the outdoor temperature is above 40 deg (adjustable Setup# 350) the thermostat will energize "Y" and "G" when there is a demand for heating.
• When the outdoor temperature is below 40 deg (adjustable Setup# 350) the thermostat will energize "W" when there is a demand for heating.

Em Heat Mode

• The thermostat will energize "W" when there is a demand for heating.