I have a Venstar T1800 thermostat with an ISY99.
I just started using heat for the first time since installation. Cool has worked correctly according to my program for the last 8 months.
I cannot seem to set the thermostats to heat through the ISY99. The webpage display changes when I toggle to heat and/or adjust the setpoint. But when I query the thermostat, the setpoint goes right back to where it began.
I just tried to set the thermostat mode to auto and the mode and setpoint seem to "stick".
Could there be a wiring or installation error ?
Thanks