Heating or cooling room thermostat diagnosis: how to troubleshoot a heating or cooling room thermostat that is not working at all or is not working properly. Here we suggest step by step procedures in diagnosing HVAC thermostat problems such as a thermostat that is not working at all or one that shows a blank thermostat display or a thermostat that does not turn heat on or off at the right ... I called Honeywell and asked them what I needed to do to attach a 24vac transformer to my thermostat and they gave me instructions on how to wire it. You might want to contact the manufacturer of your thermostat to get answers to your questions and find the appropriate wiring technique for your thermostat and hvac system.
Slide the switch on the thermostat to the desired fan setting. To exit at any time, press key until End is displayed. System Switch The System switch settings control thermostat operation as follows: Cool: The thermostat controls the cooling system. Off: Both heating and cooling are off. Heat: The thermostat controls the heating system. 1.