Heating & Cooling Combined Unit: Why isn’t my air conditioner cooling?
When your central air conditioner runs but doesn’t cool, the problem could be caused by something as simple as bad thermostat settings. If the thermostat is set to run the fan constantly but the temperature setting isn’t low enough to initiate cooling, then you can fix the cooling problem by adjusting the thermostat settings. If the thermostat is faulty and won’t signal the air conditioner to start cooling, then you’ll need to replace the thermostat.
If thermostat settings are okay, then the outside compressor and condenser unit may not be working. Check to see if the condenser fan and compressor are running. If not, check the house circuit breakers for the outside unit. Resetting the house circuit breaker may restore cooling. A bad capacitor can prevent the compressor and condenser fan from running. Many AC systems use 1 dual capacitor to help start the compressor and condenser fan. If the capacitor is bad, you’ll need to have it replaced.
If the compressor and condenser fan both run, then lack of refrigerant or a bad compressor may be preventing the air conditioner from cooling.
Several other problems such as a wiring failure or a bad compressor fan motor can prevent the AC from cooling. If you’re not able to diagnose and fix a cooling failure yourself, have a service technician repair your air conditioner.
THESE REPAIRS MAY HELP SOLVE YOUR HEATING & COOLING COMBINED UNIT PROBLEM
Replace the HVAC system thermostat
The thermostat controls the heating and cooling system in your home. The thermostat senses the temperature inside your home and cycles the system on and off to maintain the set temperature. When your HVAC system control thermostat quits working, replace the thermostat.
Hvac system thermostat
How to replace a heating and air conditioning system thermostat
If the buttons on your HVAC system control thermostat don't work or if the display panel doesn't light up, the thermostat may need to be replaced. This DIY repair guide explains how to replace a thermostat in less than 30 minutes.
Replace the compressor/condenser fan capacitor
When the central AC circulation fan inside your home runs but the system won’t cool, the dual capacitor that helps the compressor and the condenser fan start may have failed. You may hear a buzz coming from the outside unit when the dual capacitor is bad. This typically indicates the compressor and condenser fan are getting power but the failed capacitor isn’t helping the motors start.
You’ll need to have a service technician replace the capacitor when it goes bad. The capacitor can retain an electrical charge even after you disconnect electrical power from the outside unit. The technician will short an insulated screwdriver across the capacitor leads to dissipate any stored electrical charge before replacing the capacitor. The technician will also check for additional problems that could be preventing the air conditioner from cooling.
Compressor/condenser fan capacitor
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