Thermostat buttons or touch interface are unresponsive or respond intermittently.

Steps to restore responsiveness:

• Reboot device: Power cycle the thermostat to clear any software lag.
• Clean surface: Gently clean the front panel with a soft, dry cloth. Do not use liquids that may seep inside.
• Avoid pressing too hard: Use normal pressure; excessive force can damage contacts.
• Use app as workaround: Control the system via the Vaillant app if the physical interface remains unreliable.

Persistent unresponsiveness usually indicates a hardware fault; the thermostat front panel or entire unit may need replacement.