Why Is Your AC Producing Hot Air?

Posted on: 1 November 2021

Those sweltering days when the outside world seems to be an oven (and the inside of your home is threatening to do the same) can create a wonderful sense of anticipation​​—if your home has air conditioning. You confidently walk to the unit (or pick up the remote control, or shout at Alexa), turn your AC on high, and wait for the chilled air to waft over you. The trouble is that the air blasting out of the unit's ducts is warm, or even hot. Why is your air conditioner betraying you at a time when you need it most?

The Thermostat's Settings

An air conditioner that blasts hot air is a mystery and an inconvenient one at that. Unless you're a qualified HVAC contractor, there's not much you can do aside from some basic troubleshooting. Obviously, you should start by checking the thermostat. Has someone in your household inadvertently turned the temperature up, meaning the unit is doing precisely what it's supposed to do? If so, change the settings and enjoy the cold air.

Intake Ducts and Air Filters

If those settings have not been changed, you need to think outside the box. The box in question is the outside condenser. Could its intake ducts be obstructed? If so, clear the obstruction and see if the unit then produces cold air. You will also need to check the unit's air filters—located just behind the ducts on the wall (in the interior of your home). These should be regularly cleaned, and accumulated dust can result in near-total blockage, preventing chilled air from passing through them. They can be removed, washed in soapy water, and replaced. If this basic troubleshooting is unsuccessful, it's time to call in the professionals.

A Qualified Inspection

It might still be a matter of debris causing an obstruction, but when this obstruction is not immediately obvious, it can be that it's occurring inside the unit. Your AC unit must be inspected by a qualified HVAC contractor, who will clean the ducts and remove any blockage. It could be as simple as giving the unit's components a vigorous cleaning, but this must be performed by a professional. When an AC unit is producing hot air, it may also be that its refrigerant levels are too low.

Your Refrigerant

The refrigerant is a chemical mixture with heat-absorbing properties, and while it will cycle through the unit for an extended period of time, it doesn't have indefinite effectiveness. The refrigerant levels will be topped up if needed, however, the contractor will also check for leaks throughout the system, as a refrigerant leak is another potential cause for an air conditioner to produce warm air. 

In terms of the potential issues that an AC unit may face, failing to provide chilled air is at the lower end of the scale, and the solution is usually quite straightforward. Contact an HVAC contractor in your area to learn more.