DIY heating & air conditioning repair
If your furnace isn’t heating in the bitter cold of winter, or your central air conditioner quits in the sizzling heat of summer, you want it fixed–fast. You may be able to quickly get the heater or A/C working again yourself.
No matter the brand of furnace or air conditioner, our troubleshooting articles and symptoms pages can help you diagnose the cause of common problems such as why a furnace won’t ignite or why an air conditioner isn’t cooling well.
Once you’ve determined what’s broken, use the model search bar above to find the owner’s manual and illustrated parts list for your heater or A/C. Our step-by-step repair guides let you see how to replace the part and get the unit heating or cooling again.
Most common symptoms to help you fix your 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.…