This is an easy problem to solve yourself by simply removing the plastic outer casing and, with a very soft brush, delicately brushing off its coil and contact surfaces. It is most effective to clean the thermostat first at its lowest setting, then again at its highest setting.
A thermostat may periodically stick due to wear or damage, debris or sludge buildup, incorrect or low coolant, or faulty temperature sensors or wiring. These issues can cause inconsistent engine temperature regulation.
Redo the Thermostat Wiring
Other times, corrosion and lint can build up on the wiring and prevent the current from passing through. If either of these is the case, call an HVAC technician to inspect and redo your thermostat's wiring. They have the knowledge to get the issue fixed!
Thermostat is stuck on one temperature
If your thermostat is stuck, the first thing you should do is make sure your system isn't locked. Bumping into your thermostat or accidentally pressing the wrong button can result in it becoming locked, but unlocking it is a quick process.
Most modern thermostats will have a clearly marked reset button inside the panel. It's usually small and recessed, so you might need a pointed object like a paperclip to press it. For those wondering specifically how to reset air conditioner thermostat models, the process is generally the same.
Most homeowners spend between $112 and $311 to repair a thermostat. Exact costs range from about $50 to $500, with a national average of $212. The price may will depend on factors like the model you own and whether it has a warranty.
Some of the most common thermostat issues include:
The thermostat is broken, not properly level, or dusty. The thermostat needs to be recalibrated. There is loose wiring causing a thermostat issue.
You're either low on coolant or you thermostat is stuck open.
In most cases, installing a new thermostat is a relatively simple do-it-yourself project that can result in improved comfort and convenience and one that can help you save energy.
On average, most thermostats last about 10 years, depending on the model, usage, and proper maintenance. However, many people decide to replace their unit sooner to take advantage of new energy-saving technologies.
Standard thermostats: Enlist a friend or family member to assist, Position one person by the thermostat and one person by the furnace. Slowly turn the thermostat from off to heat and increase the temperature. Both the thermostat and furnace should make a sound.
So, can a bad thermostat cause your AC not to cool? Absolutely.
Replacing a Thermostat. You'll pay between $15 and $300 for the unit in addition to labor ($65 to $100 per hour) to replace an old thermostat with a new one. However, installing a brand-new thermostat is more involved and, therefore, more expensive.
Locking your Google Nest thermostat prevents people from changing settings or changing the temperature outside of a restricted range with the thermostat.
Your Vents Are Blocked
Your thermostat will not be able to reach your desired temperature if you have something blocking the vents. Check the vents around your home and make sure you do not have any items such as furniture in the way of your vent's airflow. While you're at it, make sure all of your vents are open.
Locate the sensor, which is a small, round component usually positioned near the bottom of the thermostat. It may be labeled as “sensor” or “thermistor.” Using a soft brush or a can of compressed air, carefully clean the sensor to remove any dust or debris that may have accumulated on its surface.
You can try to clean or knock on a thermostat to get it unstuck. However, that's only a short-term fix you should not rely on. Remember: a stuck thermostat is terrible news for your engine, regardless of whether it's stuck open or closed. So, the best thing you can do is replace your stuck thermostat with a new one.
Turn your thermostat to the 'off' position... Then venture off to your home's breaker box. Find the breaker to your HVAC system, flipping it 'off'. Make sure the breaker is flipped all the way 'off,' then wait for 30-seconds. Turn the breaker back 'on.
A bad thermostat can be detected when your AC or furnace is not turning on, your HVAC systems are not turning off, the thermostat not responding, your HVAC system is short-cycling, the room temperature not matching the temperature displayed on the thermostat, and the programmed setting resetting themselves.
First, check your filters and coils for dirt and debris that may be impeding airflow. Once you've cleaned the filters and coils, run the air conditioner with just the fan so that the ice accumulation can melt off. If the AC still doesn't blow cold air, it could be that refrigerant levels are too low.
If your thermostat is set to a temperature regulation mode or has an energy-saving program enabled, it might reset to conserve energy.