Why Is My AC Blowing Cold Air Outside?

Air conditioners have become essential for most households, keeping the rooms chill and cool, especially during the hot summer days. In addition, they are also excellent appliances to dehumidify the house and improve air quality. However, finding the AC condenser blowing cold air outside can be a bit worrying.

If your aircon unit is blowing cold air outside, it might be a sign that something has gone wrong and is not working efficiently. You will need to have the device inspected.

There are several reasons why your HVAC might be having the issue. We will look at some common culprits and how to fix the issue.

Regular maintenance is essential if you want your air conditioner to last longer. It improves efficiency and reduces costly repairs needed on your unit.

Should an AC Blow Cold Air Outside?

You might be wondering if the AC unit should be blowing cold air. The short answer is no.

Central and split air conditioners have two units; an indoor and an outdoor unit. The indoor unit houses the evaporator coils, fan, and motor. This part of the AC is responsible for blowing cold air into the house.

On the other hand, the outdoor unit has a compressor, condenser, condenser fan, and motor. The condenser is one of the heat transfer surfaces in the AC.

During a cooling cycle, heat in the refrigerant is absorbed in the condenser and released to the outside air. The condenser fan promotes heat transfer by blowing cool air toward the condenser fins and blows hot air away from the unit.

5 Reasons Why Your Air Conditioner Is Blowing Cold Air Outside

A condenser fan blowing cool air outside is not a good sign. If you notice the issue, you should call an HVAC technician to identify the cause as soon as possible.

Let us examine why your AC might have this issue and how to fix it.

1. Dirty Air Filters

One of the most common culprits is dirty air filters. Air filters play a significant role in an AC. They help prevent dust, dirt, and small air particles from entering the indoor unit.

However, if the AC has dirty air filters, it interferes with air circulation, which affects heat transfer. Clogged air filters reduce airflow toward the evaporator coils, causing the air around the coils to be extra cold. Because the air does not have too much heat to lose, the refrigerant does not have enough heat to release when it gets to the condenser.

Cleaning Dirty Air Filters

If your condenser fan blowing cool air is caused by dirty air filters, cleaning them should ensure the device works efficiently again. Cleaning is a pretty straightforward job as a DIY project.

The first thing you need to do is shut down your air conditioner using the circuit breaker. Take out the front panel of your indoor unit and gently remove the air filters. Some ACs have multiple filters; you must remove them all.

You can use a vacuum cleaner to suck up all that dirt and debris on the filters. Likewise, dipping the filters in water with mild detergent and cleaning them can also get the job done. However, you must wait for the air filters to dry before inserting them back into the indoor unit.

2. Refrigerant Leak

Secondly, low refrigerant levels might also cause your air conditioner to blow cold air outside. The refrigerant is used to cool air along the evaporator coils. Afterward, the compressor pumps the coolant into the condenser, where the heat absorbed from the air is removed.

However, low coolant levels caused by a leak can be a huge problem for your air conditioner. Low levels mean the unit does not adequately remove heat from the air. In the process, the refrigerant remains cold, and very little heat transfer happens in the condenser.

Refrigerant leaks can also cause damage to the compressor. The compressor needs to overwork to get to the desired temperature on the thermostat. This strains the unit, leading to more wear and tear.

Fixing a Refrigerant Leak

If you have a refrigerant leak, it is always better to let a qualified AC professional fix it. They have several tools that can help identify where the leak is coming from and refill the coolant. Additionally, if the coolant pipe has undergone too much damage, they are in a good position to replace it.

Another reason you should let an HVAC technician look at the device is if your AC uses Freon refrigerants. Due to environmental concerns, old air conditioners that used Freon or R-22 refrigerants were phased out. Purchasing the refrigerant is also controlled, and only a qualified professional is allowed to buy it.

3. Defective Compressor Capacitor

Thirdly, a defective compressor capacitor can cause the condenser fan to blow cold air. The compressor can be considered as the heart of your climate control appliance. It is responsible for pumping and circulating the refrigerant during a cooling cycle.

A compressor requires a lot of power when it starts. That is where capacitors come in. They are devices that store the electrical charge needed to start the compressor.

If the compressor’s capacitors are damaged or faulty, the compressor will have an issue during start-up. Because the compressor will not run, the refrigerant will not circulate to the condenser coils for cooling.

However, when your air conditioner is turned on, the condenser fan will continue running, blowing cold air.

Replacing a Faulty Compressor Capacitor

Fortunately, if you have a capacitor issue, you can always get it replaced. Compressors have unique capacitors depending on how much voltage they need to run. You should call an AC technician to handle the replacement to be safe and prevent expensive repairs after installing the faulty capacitor.

4. Frozen Evaporator Coils

Furthermore, frozen evaporator coils can also cause the issue. As we previously stated, aircon units also couple up as dehumidifiers. As the air gets heat removed, any moisture present condenses and forms water droplets on the evaporator coils.

The water later trickles into a condensate pan, where it collects for draining. The water is removed from the pan using a drain pipe and safely disposed of outside the house.

However, water droplets can start freezing due to insufficient heat transfer along the evaporator coils. During the cooling cycle, the refrigerant cannot absorb heat from the air. The condenser does not remove heat from the coolant, causing the fans to blow cold air.

Fixing Frozen Evaporator Coils

There are several reasons why your AC evaporator coils might freeze. The best option is to call an HVAC professional to look at the device and determine the issue.

5. Faulty Reverse Valve (for Heat Pump Owners)

Lastly, a defective reverse valve can cause the condenser fan to blow cold air. The reverse valve is a device heat pump units use when you want to switch from cooling to heating a room. This allows the pump to work both as a heater and air conditioner.

It is common for reverse valves to malfunction and gets stuck in either heating or cooling mode. When the valve is stuck in heating mode, you might notice that the outdoor unit only blows cold air.

Repairing a Defective Reverse Valve

If you have a defective reverse valve, call an HVAC expert to look at it. The valve is easily replaceable and should only take a few minutes to fix.

Summary

Are you concerned about your air conditioner blowing cold air outside? When the AC is running, the condenser removes heat from the refrigerant, causing the air around your outdoor unit to get heated up.

If your condenser fan is blowing cold air, it might be caused by dirty air filters, low refrigerant levels, or a defective compressor capacitor. In addition, you might also have trouble with frozen evaporator coils, or if you own a heating pump, your reverse valve might malfunction.