Faulty Wiring
If the wiring between the thermostat and the air conditioning system is faulty, the system may not turn on. This can happen if the wiring is old or if it has become damaged over time. To fix this issue, you may need to call a professional HVAC technician to inspect and repair the wiring.
Press the reset button. Most models require you to hold the button down for 3-5 seconds before releasing. Restore power to your AC. Restore power to the unit at the circuit breaker, and make sure the unit is set to “on” and your thermostat is set to “cool.”
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!
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.
If your AC is running but not cooling, it could be due to a dirty air filter, incorrect thermostat settings, a malfunctioning thermostat, a refrigerant leak, dirty condenser coils, blocked vents or ducts, a faulty compressor, frozen evaporator coils, or electrical issues.
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.
When your thermostat is working correctly, you can keep it as cool or warm as you need. A bad thermostat can cause your AC to not cool or heat the room to the desired temperature. Air conditioning concerns are more apparent: Your thermostat is one of the best indicators of your air conditioning system's health.
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.
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.
There are a number of reasons why your air conditioner might be running but not cooling. It could be an issue with the thermostat, the compressor, or the evaporator coils. Or, it could simply be clogged with dust and debris, which is preventing it from working properly.
Switch the thermostat to the off position. Locate the breaker that powers your HVAC system and turn it off. Wait 30 seconds and turn the breaker back on. Turn your thermostat back on and confirm it has reset properly.
When you notice that your air conditioner isn't cooling, your first action should be to turn it off. This might seem counterintuitive—after all, you want your home to be cool. However, continuing to run an AC that isn't effectively cooling can cause further damage to the system.
The cost to install a thermostat is $182 on average, but you could pay between $113 and $264. Thermostats play an important role in our daily lives, cooling us down during the sweltering summer heat and keeping us warm and cozy during winter. While the average cost to install a thermostat is $182, pricing can vary.
If your thermostat has fresh batteries but suddenly lacks power, flashes, or isn't responsive to adjustments, it may need replacement. If resetting the thermostat doesn't resolve the problem, you may have wiring problems or faulty components causing your thermostat to not turn on.
Yes, many smart thermostats are designed for DIY installation, and manufacturers typically provide step-by-step guides and videos. However, if your HVAC system is older or lacks proper wiring (like a C-wire), the installation might become more complex, and you may need professional help.
Your AC might not cool properly due to thermostat issues, an undersized unit, or extremely high outdoor temps—so check those first. Keep an eye on airflow—replace clogged filters every 3 months, and make sure vents and ducts aren't blocked for efficient cooling.
For many of us, 70 degrees is the ideal indoor temperature, but when it is close to 100 degrees outside, your AC unit will be working quite hard to meet these expectations. Consider setting your thermostat at 75 degrees to 80 degrees in your home if the outside temperature is approaching triple digits.
Power down your AC: Turn off your AC unit and unplug it from the power source. This will ensure that you stay safe while working on the unit. Locate the reset button: Most air conditioning units have a reset button located near the outside unit. It is usually a small button located inside a small hole.