It’s been another brutal summer in New Jersey, with humidity levels described as oppressive and sometimes even “miserable.” Temperatures have been sweltering, so the last thing any homeowner needs is a complete AC failure.

What Causes AC Failure?

The causes of AC failure range from the simple to the more complex. While some repair is beyond your skillset, there are other causes you can remedy quickly.

Restricted Airflow

Your HVAC system requires a clear flow of air to work properly. Warm, stale air is introduced into the equipment from the intake vent. Your AC removes the heat using a chemical refrigerant to absorb and remove it from the building. The process also removes humidity.

The resulting cold, dry air is then distributed through your home by the way of ductwork.

If the air movement is restricted during any of these steps, it can cause your AC to fail. Here are the most common causes of restricted airflow you’re likely to find in your system.

Closed vents

You may be tempted to shut off the duct vents in rooms you’re not using, but it’s not always the best choice for your AC system.

When it was installed, your system was balanced with the vents open and the intake unobstructed to provide adequate airflow through the equipment.

When your system doesn’t receive adequate airflow to operate, it interferes with the heat exchange process.

Blocked intake

Like closed vents, blocked intakes also obstruct airflow through the HVAC system. The intake is usually located near the floor behind furniture.

Dirty air filter

A dirty air filter is often the most common cause of AC failure. The filter should be changed at least every 90 days.

The air filter does more than filter to improve air quality. It mainly protects the equipment from debris in the air that interferes with operation.

That’s why it is located after the intake and before the evaporator coil — to prevent the equipment from becoming embedded with dust.

Leaking ductwork

Leaking ductwork interferes with the free flow of air throughout your home. Even worse, it often means all your cool, conditioned air is being leaked into your attic instead of your living space.

When the cold air leaks out of ducts instead of being circulated into your home, it makes your system work harder and cycle more frequently. This leads to burned out blower motors.

Damaged blower fan

The blower fan circulates the conditioned air into the ductwork and throughout your home. It can suffer a number of problems. It can become embedded with debris that causes friction, and fan belts can wear out.

Frozen Evaporator

The evaporator coils is the element of your HVAC system that produces cold air. One common cause of AC failure is when these coils freeze up.

They freeze over for several reasons. One reason is because of restricted airflow, as described above. The warm air entering the intake must flow freely into the system to maintain the coil temperature. If the airflow is blocked, the temperature in the coils drops low enough to freeze up the condensed water on their surface.

Another cause of frozen coils is a clogged condensate drain. The condensed water that forms on the coils during the refrigeration process collects in a pan beneath the unit. It employs a drain that removes the water from your home.

If the drain is clogged, then water collects, raising the humidity around the coils. Sometimes, this moisture causes a layer of ice to build up on the coils.

Electrical Problems

A very common cause of AC failure is electrical problems. It may be simply a blown circuit breaker at the electrical panel. AC failure can also be caused by a corroded electrical connection.

Frequently, a faulty blower motor that’s out of alignment vibrates and disconnects the wiring from movement.

Checking your electrical panel for a blown fuse or thrown circuit breaker could be all it takes.

Problematic Thermostat

Thermostats do more these days than ever before. Unfortunately, it also means that more can go wrong with them.

Smart thermostats are generally pretty user friendly, but make sure that you have done any redecorating that blocks the unit’s Wi-Fi signal.

Programmable thermostats come with their own host of issues, the main one being that they often run on batteries. Sometimes, it’s just a dead battery.

Low Refrigerant

The most critical cause of AC failure is low refrigerant levels. Refrigerant absorbs and removes heat from your home. If the system leaks, it needs to be repaired by a trained technician before it’s recharged.

Make an appointment today with the experts at One Hour Heating & Air Conditioning in Pleasantville if your AC fails and none of the DIY remedies work. Don’t spend another day sweltering trying to figure it out on your own.