AC Condenser Unit Blowing Cold Air Outside [Causes+Fixes]

Sometimes you might notice that your ac condenser unit is blowing cold air outside instead of hot . It can be normal for an air conditioner or heat pump condenser unit to blow cold air depending on some factors that we are going to be looking at shortly.

When your ac condenser unit is blowing cold air outside, this could be due to any of the following;

  • Stuck reversing valve
  • Incorrect heat pump orientation
  • Low freon in your system
  • Failed compressor
  • Wiring which has become loose or disconnected
  • Bad capacitor
  • Dirty air filters

While these listed factors above are the common causes for the problem, there could still be other things that can cause this problem. Let’s look at the factors and the possible fixes for each of them.

Also read: AC Blowing 70 Degree Air 

7 Factors That Cause AC Condenser To Blow Cold Air Outside


Problem 1. Stuck reverse valve

It is not uncommon for a heat pump reversing valve to get stuck in one position,whether cool or heat.

When this happens, your heat pump will keep blowing hot air into your home even when you have  set it to cool (when hot air is blown in your home, condenser unit blows cold air outside).

A common cause for a stuck reverse valve is  a bad solenoid. 

A solenoid is responsible for switching between the cooling and heating processes. Broken solenoid can cause the valve to get stuck in one position, heat position.

And when you have warm air blowing out of the vent,  you should expect cold air to be blowing out of the condenser unit.


The fix for a stuck reverse valve is inexpensive. A broken solenoid can be replaced easily and inexpensively. We recommend that you hire someone to do this specific job for you.

Problem 2. Heat Pump Orientation Settings

If your condenser unit is blowing cold air, be sure to check that you have correct change over configurations.

If you are using a nest thermostat you’ll need to change heat pump orientation on a nest thermostat.

Check your thermostat and check the setting that is there on the change over valve.


The easiest solution to this problem is to correctly set the changeover valve settings. If you are using a nest thermostat and the current setting is on B, Change it to O and turn on your ac.

Problem 3. Low Or Leaking Freon

Low freon in the AC system is the commonest cause for an ac outdoor unit blowing cool air.

The refrigerant or freon  is a chemical that is used in the refrigeration cycle to bring about cooling. Over time and due to wear of the system, this refrigerant can leak out and become very low.

When that happens, the compressor will have nothing to compress and eventually no heat will be produced in the compressor unit. If no heat is produced, the condenser fan will blow nothing but cold air.

Signs of low refrigerant include, your AC system not blowing cold air inside your home but blowing cool air outdoors.

See also: AC condenser unit running but no air blowing inside


The solution to a low or leaking refrigerant is to identify leaks, seal them off and recharge your system with more refrigerant.

There is a home diagnosis method for identifying  leaks by pressurizing your system and then flash soap water along the lines, taking note off the areas that will bubble.

This is not a recommended thing to do. The best thing to do is call a licensed professional for help

Problem 4. Bad Capacitor

An ac capacitor in the  condenser unit supplies the necessary power needed for the fan motor and compressor to start working. In other words it kicks starts the ac’ motors

The fix

A defective capacitor will be visible by the bulging of its top. But a more accurate way of testing is by using a multimeter and testing it for  continuity.

Just be sure to turn off the power at the circuit breaker and discharging the capacitor before touching anything. If the capacitor is dead, get another one for replacement.

Problem 6. Loose Or Disconnected Wires

Thermostat wiring can also be the culprit for your condenser unit to be blowing cold air outside. A thermostat must be properly wired for your system to correctly function.

When there are loose wires or disconnecting your wiring, this could cause problems.


Remove the thermostat from the wall and refer to your thermostat manual about wiring. Ensure wires are securely connected on terminals and that there are no loose wire

Problem 7. Dirty Filters

It is a well known fact that dirty filters in an AC system cause all sorts of problems and this problem is not an exception.

Filters play a big role  in AC systems in that they filter out dirt and ensure that only clean air gets to the evaporator coils.

However, when the filters are dirty, air to the coil will be restricted and might cause a condition known as low superheat in the evaporator.  

When there is slow superheat in the AC system the compressor won’t be able to compress the liquid refrigerant and  consequently will not produce heat.

That could be the reason why you ac outdoor unit is blowing coil

Also read: No Condensation from AC And No Cooling[Solved]


The best solution to this issue is to buy and replace the filters. Modern HVAC systems come with filter indicator lights, just ensure that you don’t skip replacing the filters when they are due for changing

Problem 8. Failed Compressor

If nothing works, a possible problem could be a failed compressor. Compressors are designed with a long life span, up to decades, But that doesn’t mean they can’t malfunction before their time comes.

Read also: Can You Run AC Without The Condenser Fan Running?


If you think your compress is defective, you may want to buy another one to replace it. But compressors are nearly as expensive as the whole system.

You may want to consider contacting  HVAC professionals  with advice regarding whether or not  to replace the compressor or the whole system.

Final Thoughts

By the end of this article, we hope that you have fixed your problem. If the condenser unit is still blowing cold air , we recommend that you call an HVAC technician for help.

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