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DIY: How to Fix an Air Conditioner that Blows Hot Air


In the dead of summer, the last thing you need is a broken air conditioner blowing hot air into your home. If your air conditioner is blowing warm air, follow these steps to troubleshoot so you can get right back to comfortable temperatures.


What you'll need:


Step 1: Rule Out Errors With the Settings

Sometimes, the dials and switches on your unit can be accidentally set on the wrong options. Before you start to take everything apart, check all the settings to ensure that your air conditioner is set to cool and not just to vent. If it is, simply flip the switch back to the proper position and see if the unit cools again.


Check the settings of your air conditioner
Make sure to replace your air filter

Step 2: Replace Your Air Filter

Dirt that obstructs the airflow in your air conditioner can cause it to malfunction or burn out over time. Cleaning off the unit may help it blow cool air again. If it's been more than 30 to 90 days since you've replaced your filter, you should replace it. If it hasn't been that long but you notice dirt buildup, clean the filter with a soapy rag.


Step 3: Clean Condenser Coils

Condenser coils can be cleaned using a soft brush and a vacuum. Turn off and unplug the air conditioner, and then use a soft brush to loosen residue before cleaning it up with a vacuum cleaner attachment.


Keep the condenser coils clean
Make sure to monitor refrigerant levels

Step 4: Check Refrigerant Levels

If your air conditioner has the proper settings and is fully cleaned, low refrigerant is the most likely cause of your hot air problems. Over time, your air conditioner will use up its stores of refrigerant. In many states, it is illegal to purchase and handle refrigerants for a DIY repair. Since these substances can be very dangerous to work with, it is typically best to leave this job to a service technician. In addition, your service technician can check the unit for potential leaks.


DIY: How to Fix an Air Conditioner that Blows Hot Air - Sears