Does this thermostat work (fully communicating) with both an ACIQ-48-HPD / ACIQ-60-ACL-B and a modulating furnace like the ACIQ G97MN1202422. Or do you have to go to the ION thermostats in order to communicate with the variable speed/modulating furnace?

The TL04-1 utilizes HA/HB communication protocol, which communicates directly with inverter heat pumps/condensers (such as the ACIQ-48-HPD) or operates via standard 24V conventional thermostat wiring. However, 24V control cannot drive true, continuous variable modulating firing rates on the G97MN furnace; it will force the furnace to operate as a staged unit governed by internal timer logic.

To get full communicating control (variable modulating gas valve control, variable airflow modulation, and system feedback) with the G97MN modulating furnace, you must use the ACiQ Ion™ System Control (Model SYST0101CW). The Ion controller is specifically designed to handle the proprietary communicating protocols required for modulating furnaces (G97CMN/G97MN series).

If you have any further questions, please call us and we will be happy to assist you.