my wyze thermostat makes a quiet but annoying clicking sound every few minutes, is that normal?

Diagnosis

The clicking sound you hear is the mechanical engagement of the internal relays. These are physical switches that open and close to send 24V AC power to your HVAC system's control board. In a healthy installation, you should only hear a click when the thermostat triggers the heat or cool cycle to start or stop. If you hear this sound every few minutes while the system is supposedly idle, you are experiencing "short-cycling." Short-cycling occurs when the thermostat rapidly toggles the relay on and off. This is typically caused by the thermostat being positioned too close to a draft (like a window or air vent) or being installed in a "hot spot" where the internal temperature sensor reads a rapid fluctuation. When the temperature fluctuates by even half a degree and your settings are too tight, the relay clicks to compensate, even if the actual room temperature hasn't meaningfully changed. This puts unnecessary wear on the relay and can lead to premature failure of your HVAC blower motor or compressor.

How to Fix It

To stop the frequent clicking, you need to adjust the temperature differential (the "swing") to prevent the system from reacting to minor temperature fluctuations.

1. Open the Wyze App and select your Thermostat from the device list.
2. Tap the Settings (gear icon) in the upper right-hand corner of the thermostat control screen.
3. Navigate to Advanced Settings.
4. Locate the Temperature Swing or Differential setting. If this is set to 0.5°F, the system will trigger almost instantly. Increase this value to 1.5°F or 2.0°F. This creates a larger "buffer" zone, meaning the temperature must drop or rise further before the relay clicks back on.
5. Save the settings and monitor the unit for 30 minutes.
6. If the clicking persists, check your Cycle Rate settings (if available for your specific HVAC configuration) and ensure it is set to a standard interval to prevent rapid-fire switching.

If That Didn't Work

• Inspect for Air Drafts: Check if there is a hole in the drywall behind the thermostat where the wires come through. Air from inside the wall can blow directly onto the sensor, causing the thermostat to think the room temperature has changed instantly. Use a small piece of plumbers putty or foam insulation to seal the hole around the wire bundle.
• Check the C-Wire Voltage: If you are using a Wyze Power Extender instead of a dedicated C-wire, the thermostat may be experiencing "power pulsing." If the voltage drops below the threshold, the relay can trip or reset. Verify that your 24V transformer is providing a steady current; a fluctuating power supply can cause the relays to chatter.
• Relocate the Thermostat: If the unit is installed directly opposite a supply vent, the "cold air dump" will trigger the relay to shut off immediately after starting, then click back on once the air clears. Move the thermostat at least 3 feet away from any direct airflow sources.
• Perform a Hard Factory Reset: In rare cases, a firmware glitch can cause the relay to loop. Remove the faceplate from the wall, wait 30 seconds, and snap it back in to power cycle the logic board. If the clicking continues, use the app to perform a full factory reset and re-pair the device.

Heads Up

• Compressor Protection: Frequent clicking/short-cycling can kill an AC compressor. If you hear the relay clicking but the outdoor unit isn't starting, stop using the system immediately to avoid burning out the start capacitor.
• Battery Health: While the Wyze Thermostat is primarily powered by the HVAC system, erratic relay behavior can sometimes be a symptom of a failing internal capacitor on the device's circuit board.
• Avoid Tight Tolerances: Never set your temperature swing to the absolute minimum (0.5°F) unless you have an extremely stable environment, as this will significantly shorten the lifespan of the mechanical relays.