Why Is My Air Conditioner Blowing Warm Air?

Woman pushing buttons on air conditioning thermostat

Our homes are supposed to provide us a place to escape the summer heat, and discovering that your air conditioner is blowing warm air can really ruin a hot day. Sometimes, you may be able to resolve the issue yourself – or at least narrow down the cause. We’re always here to help no matter how small or large your home HVAC issue, but it helps to understand what’s going on with your system.

Common Reasons for Warm Air

Here are some common reasons your air conditioner is blowing warm air:

Thermostat issues

Accidentally setting the thermostat to heat can cause warm air to blow from your HVAC, but the problem with your thermostat isn’t necessarily that simple. The battery in your thermostat might need to be replaced. Also, remember that if you turn the thermostat to ON rather than AUTO, the system may blow warm air when the compressor isn’t running. Set the thermostat to AUTO and 78 degrees for the best results during the summer.

Circuit breaker problems

In some circumstances, the fan could have power even if the condenser doesn’t, so check the circuit breaker to make sure it isn’t tripped – or if the home is older, that you don’t have a blown fuse. To reset a circuit breaker, first turn it to the off position before trying to turn it back on. If the breaker trips a second time, there may be a problem that requires repair by a professional HVAC service technician.

Dirty evaporator coils

If the air filter is dirty, this could have caused the evaporator coils to get dirty, and this can cause your HVAC unit to blow warm air in the summer. Coils can even freeze up, impeding air flow. Turning the unit off for several hours, changing the filter and then restarting it may solve this problem. But dirty coils need professional cleaning as soon as possible. Note that the problem could be with coils inside your home or at the outdoor unit.

Low refrigerant

Your system could also be low on refrigerant, which could be caused by a leak that requires a fix from an HVAC service technician since even modern refrigerants can be dangerous.

Clogged or Blocked Condenser Unit

The condenser unit is responsible for releasing the heat from the refrigerant, so if it becomes clogged or blocked, it can cause the air conditioner to blow warm air. Dirt, debris, leaves, or other obstructions can prevent the condenser from working properly. Regular cleaning and maintenance of the outdoor unit can help prevent this issue.

Faulty Compressor

The compressor is the heart of the air conditioning system, responsible for compressing the refrigerant and moving it through the system. If the compressor fails, it can cause the air conditioner to blow warm air. Signs of a faulty compressor include unusual noises, vibration, or the unit not turning on at all. Hire an expert A/C repair technician that can diagnose and fix this issue.

Damaged Ductwork

The ductwork in your home carries the cooled air from the air conditioner to each room. If there is damage to the ductwork, such as holes, leaks, or disconnected sections, it can cause the air conditioner to blow warm air. In addition to affecting the cooling efficiency, damaged ductwork can also allow contaminants like dust and mold to circulate through your home. A professional HVAC technician can inspect and repair the ductwork to ensure proper cooling and indoor air quality.

Getting Help

If you need help getting your a/c system working again, don’t hesitate to contact us. Fixing malfunctioning HVAC systems is what we do every day – and there’s a solution for every kind of problem. Why not contact us today and schedule a service appointment?

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