A bad thermostat can cause your AC to not cool or heat the room to the desired temperature.
A bad thermostat could certainly cause the ac not to work. You can check the t'stat by removing it from the wall and jump the red wire to the yellow (R to Y) at the wall plate. That should cause the outdoor ac to run. If it does run then the t'stat is bad.
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.
It is not recommended to bypass a thermostat for an air conditioning system, as it can lead to safety hazards and damage to the system. Additionally, bypassing the thermostat can result in decreased energy efficiency and higher energy costs.
Checking basic thermostat settings, power supply components, and air filter conditions are essential to troubleshoot why an AC unit isn't turning on. More advanced issues requiring professional attention include faulty wiring, a malfunctioning outdoor unit, a bad capacitor, or incorrect thermostat calibration.
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.
The main reasons your AC unit outside is not turning on could be something that has tripped the circuit breaker, something is blocking the fan's airflow, or the condensing unit is damaged. Other potential issues could be the thermostat isn't set correctly or the compressor could be malfunctioning.
Don't fret. Your thermostat is a small but important device. Without it, you wouldn't be able to turn your air conditioning system on and off, or program your cooling and heating settings to your liking.
A central AC system consists of indoor and outdoor units. An indoor air handler can continue running when the outside unit has shut down. While air will blow from the vents, it won't be cooled; it may be as warm as the summer air outside.
Any time you are having an issue with heating and cooling units, such as after a sudden power failure or after your children have had 'control' of the system while you've been away, resetting the thermostat should be the first thing you try when attempting to rectify HVAC system issues.
A malfunctioning thermostat has a harder time maintaining a setting, and may quickly shift temperature settings with no warning. If your central air has a difficult time maintaining the set temperature, even after lowering a setting for a test trial, it could be the thermostat.
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.
Common Reasons Why Your Air Conditioner is Not Turning On
Resetting your thermostat is often all that's necessary to get it working again. A tripped circuit breaker is another common reason why your AC won't turn on. Using too many appliances at once can trip the circuit breaker.
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.
A malfunctioning thermostat will have trouble keeping your home's temperature at the right setting. If there's something wrong with the motherboard, it may change its own settings at random. You can test the thermostat by lowering the settings to see if the problem persists.
Absolutely. While it may seem like a small part of your HVAC system, the thermostat plays a crucial role in ensuring your home stays cool and comfortable. If you're experiencing issues with your AC not cooling properly, checking the thermostat should be one of your first steps.
Your thermostat reads the temperature of the room, then sends an on or off signal to the air conditioner. The AC itself isn't detecting the temperature in your home, so it has to rely on the thermostat.
The thermostat is blank but the fan works, what does that mean? If the display is not working but the fan is on and your thermostat is in the “auto” position, this is because the display controls the heating and the AC but in the “auto” position, the fan can automatically come on and off.
Check Your Circuit Breaker
Locate your main circuit breaker and switch it back to the "On" position. Wait 30 seconds and turn on your air conditioner again. If it still doesn't work, you'll need to call a professional for help.
Clogged air filters are one of the most common reasons a thermostat clicks but AC does not turn on. A filter cleans the air before it circulates throughout your home, trapping dirt particles, dust, and pollen. Over time, these contaminants will clog the filter, limiting airflow to the HVAC system or furnace.
When the outside unit breaks down but the inside unit is running, the culprit may well be a broken compressor in the outside unit. That's typically a major repair, something that might even warrant a system replacement.