i set my honeywell t9 to cool but the house is still heating up, it's not responding, help?

First, confirm the system is in Cool mode and the set point is correct.

• Press Menu > System Mode > Cool > Done.
• Make sure your desired cooling temperature is lower than the current indoor temperature shown on the screen.

If that's set right, check the basics:

• Circuit breaker for the HVAC system.
• Power switch at the furnace/air handler.
• Furnace door is shut securely.

Wait 5 minutes after making a temperature change for the system to respond.

IF THAT DIDN'T WORK: For heat pump systems, a common miswire causes this. Verify there is NOT a wire attached to the W terminal on the thermostat's UWP (wall plate). If there is, you'll need to reconfigure the wiring.

HEADS UP: Cooling mode only works within a range of 50°F to 99°F (10°C to 37°C). Setting it outside that range won't trigger the system.