Troubleshooting Tips | AC Blowing Warm Air

Troubleshooting Tips | AC Blowing Warm Air

Troubleshooting Tips | AC Blowing Warm Air

Although fall is bringing cooler temperatures, there remain days when the home’s air conditioner is needed. You expect the AC to cool your home when you need it. Unfortunately, for a number of potential reasons, sometimes when you turn the unit on, the AC is blowing warm air. The following troubleshooting tips can potentially assist you in determining the cause, and may provide a quick fix without the need to call for a technician. However, if this guide fails to restore your air conditioning’s cooling, contact Cypress Heating and Air Conditioning for repair when the AC is blowing warm air.

Improper Thermostat Setting

We have all set the thermostat to manual fan at some time. It can provide air circulation when the house is stuffy, though not hot. Sometimes, we forget to reset the thermostat, resulting in a continuous running fan and no cooling. Check the thermostat settings to ensure the fan is on automatic, and the setting is on cool. Otherwise, it will appear the AC is blowing warm air.

Check the Breaker

Inside the home’s electrical panel, is a breaker for the HVAC system. Ensure the breaker is “ON”. If you are not certain, turn the breaker off and back on again. Check the system for operation by lowering the thermostat. After all, if the inside temperature is 75, the thermostat setting will have to rise to 76 before the air conditioning will cut on. 

If the breaker was “off”, and restoring it triggers it to trip again, there is likely a problem with either the air conditioner or the breaker. Contact a Cypress HVAC technician for repair. 

However, if the breaker does not trip again, and lowering the thermostat does not restore AC function, check for an outdoor breaker near the outdoor condensing unit in a service box. If one is present, check its breaker and if tripped, turn it back on and check for AC operation. Breakers are a common cause for the AC blowing warm air. Electrical surges due to issues with the power grid can trigger a thrown breaker.

Dirty Filter

Check the filter and replace if dirty. An extremely dirty filter can cause a lack of adequate airflow and can result in the compressor freezing up. A dirty filter will also result in a dirty system and ducts, and can cause damage to components.

Condenser Coil Needs Cleaning

Ensure the area around the exterior unit is clear to provide adequate airflow. This includes plants, shrubs, debris, or other objects. If the condenser coil is in need of cleaning, contact a Cypress technician for service.

Evaporator Coil Needs Cleaning

In a split system, the interior coil is called an evaporator coil. The air filter is located in this area, and helps to protect the evaporator coil from soiling. The coils will require cleaning at some point, though the routine changing of the air filter will reduce the required frequency. A dirty coil in either location can cause reduced performance, including the AC blowing warm air.

Refrigerant Leak

A refrigerant leak is a common cause of the AC blowing warm air. The repair of a leak requires the services of an HVAC technician. Leaks are not always as simple as adding refrigerant. First, the leak will need to be located and repaired. Without repair, the refrigerant will leak away once again. It is also possible that the technician will need to evacuate the system, which utilizes a vacuum pump to extract moisture and air before refrigerant can be added. There are potential signs of low refrigerant depending on the amount that has leaked out, and the amount of time that has passed:

  • The refrigerant line is frosted over 
  • The sound of bubbling or a hissing noise 

Furthermore, low refrigerant is due to a leak that requires repair. The AC is a closed system and as long as there is not a leak, additional refrigerant is not required. A refrigerant leak can lead to costly damage to the HVAC system. It is to the homeowner’s advantage to schedule a repair promptly.

Cypress Heating and Air Conditioning’s technicians are certified and experienced HVAC experts with the expertise to provide for all of your needs with your heating and air-conditioning in Katy, TX. Our highly trained professionals provide repair, installation, and service. If these troubleshooting tips were unable to resolve the issue of the AC blowing warm air, give us a call. We serve Katy, Plano and the surrounding areas, and are a member of the BBB with an A+ rating.