Heating and air conditioning symptoms
When your heater or air conditioner is running but not heating or cooling, not running at all or leaking water inside the house, you'll need to take action fast. Our symptoms and troubleshooting solutions guide you through the steps to fix common heater and air conditioner failures. Get the repair parts you need by entering the part number or your HVAC system model number in the search bar. Follow the steps in the heating and air conditioning repair guides to install replacement parts and get the HVAC system working again.
Symptoms common to all heating & cooling combined units
Choose a symptom to see related heating and air conditioning system repairs.
Thermostat problem, clogged air filter, burner failure…
Dirty air filter, clogged condenser coils, low refrigerant charge, faulty compressor…
Thermostat problems, bad compressor/condenser fan capacitor, lack of refrigerant, failed compressor…
Dirty flame sensor, failed flame sensor, damaged burner, bad high limit switch…
Main causes: errant thermostat settings, lack of electrical power, clogged drain line, wiring failure, control failure.…
Main causes: Errant thermostat settings, lack of power, bad interlock switches, lack of exhaust ventilation, wiring fail…
Most common repair guides to help fix your heating & cooling combined units
These step-by-step repair guides will help you safely fix what’s broken on your HVAC system.
How to unclog the air conditioner drain line
The condensate drain line for your central air conditioner can clog with mold and mildew. Water will back up and start d...
How to replace the furnace flame sensor
The flame sensor detects when furnace burner flames are lit. You may need to replace the flame sensor if flames only sta...
How to replace a heating and air conditioning system thermostat
The control thermostat for your HVAC system can stop working. This repair guide shows how to replace it....
Effective articles & videos to help repair your heating & cooling combined units
Use the advice and tips in these articles and videos to get the most out of your HVAC system.
Learn how to maintain your central air conditioner to keep it running smoothly all summer long....
Learn about all the convenient features on our Sears PartsDirect website that make your parts purchases easier....
Get answers to frequently asked questions about Sears and Sears PartsDirect....