It seems the only times your HVAC system doesn’t work is when record heat sets-in, right in the middle of the day, or, when you’re exhausted, ready to get a good night’s sleep. Suddenly, you find it getting warmer and warmer in your home, even though you can hear the air conditioner whirling outside and feel air blowing through the vents. As the temperature rises and the thermometer begins to steady rise, so does your level of discomfort.
Most Common HVAC System Problems
You know little to nothing about how your system works, but, you want to at least attempt a quick fix. The first thing to do is inspect the unit itself. If there’s ice accumulating on it, that’s certainly a telltale sign there’s something wrong and needs to be addressed immediately. Should the air conditioner not even turn on, you ought to check your home’s breaker box to see if a breaker has tripped.
Air conditioner manufacturers generally make rugged, high quality products. If your air conditioner fails, begin by checking any fuses or circuit breakers. Let the unit cool down for about five minutes before resetting any breakers. If a central air conditioner’s compressor stops on a hot day, the high-pressure limit switch may have tripped; reset it by pushing the button, located in the compressor’s access panel. —U.S. Department of Energy
Another thing to check is the thermostat itself. Depending on the type, it might need batteries, or, no longer works. Though these scenarios do happen, there are more common reasons an HVAC system might not function properly or work at all:
- Low refrigerant. Most people know this as “freon,” the cooling refrigerant that makes all the cold air magic happen. When the refrigerant level drops, it could indicate a leak, or, a problem with the refrigerant system. In about 9 out of 10 cases, a leak is to blame for low refrigerant levels. While this is generally an easy and relatively inexpensive fix, just recharging it won’t be enough for the long term.
- Worn contactor. Within your air conditioning unit, there are three contactors: one for the blower motor, one for the compressor, and another for the condenser fan motor. These start the motors and the compressor. When contactors are damaged, electrical current cannot easily pass or pass at all.
- Frozen coil. When a coil freezes, it could be for different reasons. One reason is due to low refrigerant levels, while another is due to poor or obstructed air flow. Of course, low refrigerant can mean a leak, or, a problem with the refrigerant system. Poor or obstructed air flow can mean a blocked return air duct or filthy filters. This is why you need to regularly change the filters.
- Compressor. The compressor is located with the condenser coil, and, is the heart of your system. Improper refrigerant levels can do quite a lot of damage to your system: too little, and the compressor will heat and eventually seize, while, too much, and cause liquid slugging.
- Condenser coil. This is located outside with the unit and is susceptible to dirt and debris. When dirty, it becomes clogged, which can actually be clean with a garden hose. However, if the grime is significant, a special chemical will be needed.
Another common problem is with the evaporator coil. If it cracks, it will either needed to be repaired or replaced, depending on the extent of the damage and the age of the component.