What to Do When the Thermostat Clicks But Nothing Happens

Regardless of the season or outdoor temperature, you rely on your thermostat to signal your HVAC system to turn on. It’s an unforgiving experience when the thermostat clicks but nothing happens. You’ve come to expect a prompt response. Instead, you’re left uncomfortable and wondering what to do.

Here are a few tips to help you troubleshoot and possibly fix the cause of the problem:

The Air Filter Is Dirty

If the thermostat clicks but the AC or furnace doesn’t turn on, most often it’s because the filter is clogged. A blocked filter will restrict airflow. The particles it’s designed to trap eventually clog the filter media, and the system will be unable to generate heat or cool air. To avoid this scenario, change the filter every 60 to 90 days and consider investing in a higher-quality one that screens out even smaller particulates.

Adjust the Thermostat

If the thermostat clicks but nothing happens, the setting it's on may be the reason. For example, it must be set above the current room temperature for your furnace to turn on. This can be resolved by turning the thermostat up to the highest setting. If the furnace kicks in, turn down the temperature so your home doesn’t get too hot. Also, make sure the thermostat is in “Heat” or “Auto” mode and that the fan is set to “On” or “Auto”.

If adjusting the thermostat doesn’t help, check whether it has malfunctioned. Look for loose wires or relay connections that you can tighten. Or, turn off the breaker to the unit, wait a couple of minutes, and turn it on again (or reset the breaker if it has tripped). The thermostat should start working; if not, it may need to be replaced.

Check the Furnace’s Power Supply

Find the circuit breaker for the furnace if nothing happens when the thermostat clicks. All furnaces need electricity to run. If a breaker has tripped, flip it on and see if your furnace starts running. If the breaker trips again, contact a professional to look at the system.

Check/Clean the Ignitor

A pilot ignitor coated in debris won’t ignite the furnace, even if the thermostat clicks on and sends the right signal. To access the ignitor, remove the furnace’s front panel. Identify whether the ignitor is dirty or clogged. But unless you have experience working with furnaces, call an HVAC professional who can safely deal with the problem.

Restore the Gas Supply

For a gas furnace to work, the gas valve must be open. The thermostat will click as usual. But if you don’t get heat, one place to look is the gas valve. If it’s closed, turn it carefully to a parallel position with the pipe, and the gas should start flowing.

Inspect the Capacitor

A faulty capacitor can be the reason the thermostat clicks but nothing happens. The capacitor stores an electrical charge, which starts the compressor when a signal from the thermostat is received. If the capacitor has gone bad, you may hear a buzzing sound as the thermostat clicks. This means it's trying to start the system but doesn’t have the charge to do it. Since a capacitor is a high-voltage component, it’s best to call a service professional to fix the problem.

Call NEXGEN If the Thermostat Clicks But Nothing Happens

We provide heating and air conditioning installation and repair throughout Southern California. Our friendly technicians are prompt and committed to ensuring the success of every job, no matter how big or small it is. NEXGEN is renowned for its high-quality service and competitive pricing for all types of HVAC, plumbing, and air quality equipment. If necessary, we’ll even provide you with a new or updated programmable or smart thermostat. Feel free to book service online today!