setup for Honeywell Th8320U thermostat

Old 04-21-14, 02:03 PM
Thread Starter
Join Date: Sep 2013
Location: United States
Posts: 1
Received 0 Votes on 0 Posts
setup for Honeywell Th8320U thermostat

I purchased a house with three zones and six thermostats. The house has one AC and heat pump unit with variable speed fans and three sets of dampers for the three zone. It also has hot water radiator heat that is on fuel oil. Three thermostats are Honeywell TH8320U and controls the AC/HP. Three other thermostats are Upnor and basic thermostats, 2 wire type, and control the zone pumps of the radiators that is connected to the oil boiler.

I wanted to update the controls to the hot water radiator system so that it is also controlled by the Honeywell. I have installed the outdoor temperature sensors and they are working. I have connected relays (coils) to the aux. terminals so that the hot water system is controlled by the Th8320U also. What I wanted is to have the radiator heat to come on and the heat pump off when the outside temperature is below 35F. I set the system type code (0170) to 7 and that seems to not work. It is calling for heat on the TH8320 but the lights on the Lennox harmony is showing that is call for cooling!

Is it possible that the system test must be set to all off (0) before exiting that menu? Or it it some other problem? I tried changing the change over valve (0190) to 1 instead of 0 and got error message from the Lennox unit that it is both trying to heat and cool.

Any suggestion as to what is wrong and how to fix?

Thank you,
Old 04-22-14, 06:53 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,425
Received 17 Votes on 14 Posts
Post the model number of your outdoor unit.

Post the model number of your Harmony so that we can see if it requires you to configure the stat for heat pump operation.

I recommend the Honeywell Prestige IAQ for your application.

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: