Let's walk through this step-by-step. First, make sure the thermostat is actually calling for heat correctly.
- On the thermostat, press the Menu area.
- Go to System, then Mode.
- Set the system mode to Heat. Press Done.
- Now, set your desired temperature using the up arrow. Make sure it's set higher than the current indoor temperature shown on the screen.
If it's set correctly and still nothing:
- Check your circuit breaker for the HVAC system and reset it if needed.
- Make sure the power switch at the furnace itself is on.
- Go to the furnace and ensure the door is closed securely. It won't run if the safety switch is disengaged.
- After making a change, wait a full 5 minutes for the system to respond. It has built-in delays to protect the equipment.
IF THAT DIDN'T WORK: This could point to a wiring issue. Double-check that the wire labeled 'W' (for heat) is firmly inserted into the W-terminal on the thermostat's wall plate. Give it a gentle tug to confirm.