The Three Most Likely Reasons Why Your Air Conditioner Won't Work

When you turn on the air conditioner and warm air (or no air) comes out, it's obvious that something is wrong. Having your air conditioning fail is never fun, but thankfully, most common causes of AC failure are rather easy for your HVAC technician to address. Here's a look at the most likely reasons why your AC is not working -- and what you can expect your HVAC company to do about them.

Bad Thermostat Wiring

Especially if your thermostat and the wiring have been around for many years, there's a good chance your air conditioner has failed due to a wiring problem. If you cannot get the heat to turn on or even the central air to run either, a bad thermostat connection is likely to blame.

Luckily, this should be quite easy for your HVAC technician to address. They'll just remove the thermostat from the wall, reconnect the appropriate wires, and perhaps run a new wire or two to replace any that are showing wear. The whole process should take an hour or less. In the worst case scenario, you may need a new thermostat, which will run you about $20 - $80 for a basic model.

Refrigerant Leak

Refrigerant is the liquid that runs through your air conditioner's coils. When heat blows past it, the refrigerant expands into a gas and absorbs the heat, removing it from your home's air. If the refrigerant starts leaking, your air conditioner will slowly grow less and less effective until the air it blows out eventually becomes warm. 

You can detect a refrigerant leak by placing a piece of white paper beneath your AC coil. Come back a few hours later. If you see pink or green liquid on the paper, that's refrigerant. Your HVAC contractor can repair the leak and add new refrigerant to your system, which should get your air conditioner working again.

If you have an older air conditioner made in the early 2000s, you may run into a small glitch in the case of a refrigerant leak. The refrigerant used in these units, known as R-22, is being phased out and is hard to come by. You may need to wait for your HVAC contractor to order it, and the costs can be higher than for a more common refrigerant, like R-401A.

Frayed or Split Blower Motor Belt

The blower motor is an essential part of your air conditioner. It's responsible for powering the fan that drives the cooled air through your home's ducts. Like any motor, this motor features a belt that converts power generated in the pistons to physical motion. As the air conditioner ages, this belt may begin to fray or split. If your AC unit has been making squeaking noises, a frayed belt is likely to blame. Eventually, if you keep running the air conditioner, it will stop blowing out air completely because the belt will split completely, causing the motor to fail.

Replacing a motor belt is not a terribly tough job for an HVAC technician. However, it may take a few days as they'll have to order a new belt and perhaps some new screws and wires to use in conjunction with it. If you've been running the air conditioner with a damaged belt for a while, some of the ball bearings may also be damaged; your HVAC contractor can replace them, too.

While these are not the only problems that an air conditioner can develop, they are three of the most common ones. If your AC unit has not been working properly, contact a business such as A-1 American Services.