Thermostat displays E9 and may not respond to touch or button presses reliably.

Safety first: Turn off power to the HVAC system before removing the thermostat from the wall.

• Clean the screen: Wipe the touchscreen gently with a soft, dry cloth. Do not use liquid cleaners that can seep into the edges.
• Power reset: Remove the thermostat from its sub‑base for 30–60 seconds, then reattach. This forces a reboot and can clear temporary UI errors.
• Inspect connectors (advanced): If the housing can be opened, carefully check the flat ribbon cable between the display/touch panel and the main PCB. Reseat the connector if it appears loose.
• Check for moisture damage: Look for condensation, corrosion, or water marks inside the thermostat. If present, the unit is compromised and should be replaced.
• Firmware update: If accessible via app or USB, update the thermostat firmware to the latest Payne release.
• Replace thermostat: If E9 persists and touch remains unreliable, the display assembly is defective. Replace the Payne smart thermostat.