The compressor is an integral component of a home’s air conditioner or heat pump. A compressor is a pump, and its role is to pressurize or compress the refrigerant returning from inside the home. The compressor forces this compressed refrigerant into the condenser coil. The large fan outside your home draws air through the system.

It passes over the coil where heat energy exchanges between the coil and the ambient air. A compressor undergoes significant wear and tear each cooling season. It’s a primary reason a seasonal cooling tune-up is so important. When a compressor malfunctions, it can manifest in a wide range of symptoms. Let’s explore a dozen of the most common.

1. Increased Electricity Consumption

Increased electricity consumption is often the first sign there’s something wrong with your compressor. This is a reason it’s a good idea to track your energy costs month to month and year to year. You may also want to consider a smart thermostat with energy monitoring. Such units can detect quickly that the AC is drawing more power than usual and that you need to schedule service.

There are several reasons that a compressor may draw more power. The pumping cycle may be longer than usual because of inefficiencies in the system, such as a dirty condenser coil. The motor may also wear out due to inefficient lubrication, a bad ball bearing or a faulty capacitor. These factors can lead to increased draw, which can go on for a while before the system short-circuits.

2. AC Won’t Start

It’s important to note that there are many reasons that your AC may not start. It can be as simple as a clogged air filter or a thermostat with dirty contacts. Sometimes, it may be a more serious issue related to the compressor. Perhaps the compressor fuse has blown. That is a relatively simple fix, but it could suggest a more serious issue with the pump. It may also be that the compressor pump has died. If that’s the case, the system will be unresponsive, and newer thermostats may have a blacked-out display.

3. Lack of Hot Air Released Outside

The outdoor unit of an AC or heat pump houses the compressor, fan, condenser coil, refrigerant lines and various electrical components. The fan draws air through the system and exhausts it upward toward the sky. That air should feel noticeably hot. If the exhausted air doesn’t feel much different from the ambient air, it could indicate a problem. It may mean that the transfer of heat energy between the condenser coil and ambient air is not occurring efficiently.

4. Short and Long Cycling

AC cycles vary depending on the home and model. That said, the typical AC cycle is between 10 and 20 minutes. If the system is starting and turning off quickly, it can be because the compressor is not creating enough pressure. It can also be because of reduced pressure within the refrigerant line itself.

If the compressor is operating inefficiently, it can also lead to cycles longer than 20 minutes. The system isn’t achieving the necessary cooling, and so the thermostat keeps it running. Note that there are many other causes of improper cycling. These include a clogged air filter, electrical issues, a dirty condenser or evaporator coils and faulty thermostats.

5. Excessive Vibration and Loud or Unusual Noises

A compressor in need of maintenance can lead to a range of unusual and even loud noises. Clicking, ticking and chattering noises often suggest an electrical problem. Rattling or rumbling may indicate that the motor mounts are loose and allowing the compressor to vibrate.

An AC compressor may also vibrate excessively. This is usually because of inadequate lubrication. However, it can also be because of bad ball bearings and other parts. A hard-starting compressor may eventually graduate to a loud banging or popping noise on startup.

6. Tripped Circuit Breakers

The compressor is the main draw of electrical power in an AC system. If it short-circuits, it can trip its circuit breaker. A compressor can also trip a breaker during a hard start because of irregular power draw. If you experience a tripped circuit breaker, it may be an isolated event. It’s all right to reset it and start the system. If it trips again, don’t keep resetting it. Call your technician. Your AC tripping a circuit breaker should be an uncommon event. Even several times a month suggests that something is wrong.

7. Weak Airflow

The most common causes of weak airflow from your vents are a clogged air filter and obstruction in the ducts. You may also have a problem with your blower operating at a lower speed. If those aren’t the problems, it could be the compressor. You may need to replace your system’s expansion valve. It can also be that the compressor has weakened to the point of not providing enough airflow and pressure.

8. Warm Air Flowing From Vents

A common AC problem is the system running but blowing room-temperature air out of the vents. There are many causes for this, including a clogged filter or a clogged condensate line. The condenser pump is a potential cause as well. First, check that there isn’t an abundance of leaves and other debris in your outdoor condenser unit. That can restrict airflow and create this problem. It can also be that the compressor isn’t pressurizing the refrigerant enough or that there’s a leak or bad valve.

9. Warm Spots in Rooms

You may have weak airflow and/or warmer than usual air but never notice them. It may only be noticeable if you hold your hand to the vents. Eventually, those issues can cause warm spots in rooms. You may also have one room that simply feels warmer than the rest. In a multilevel home, a temperature difference between floors of 2 degrees or more may also suggest a compressor problem.

10. Excess Moisture

Some condensation around your compressor is normal. If the moisture is dripping outside the outdoor unit and even puddling around it, that is excessive. It may indicate a problem with the compressor itself. It can also reflect other issues, including problems with drainage and refrigeration.

11. Outdoor Unit Icing Up

Excess moisture can ice up on the components within the condenser unit. You can also experience icing over of the compressor and condenser coil because of restricted airflow and refrigerant issues. If you notice ice, turn off your AC and call your HVAC technician.

12. Leaking Refrigerant

Most refrigerant leaks are micro-leaks that go unnoticed without professional maintenance. If you have puddling around the outdoor unit, it could be refrigerant and not water. This could be because of a pump malfunction, a rupture in the refrigerant line or a bad connection between them.

Expert AC Repair in San Marcos

Oak Island Heating and Air Conditioning has repaired AC and heat pump compressors throughout San Marcos and the surrounding areas for more than 20 years. Our HVAC technicians also install and maintain ACs and heat pumps, and we specialize in furnaces and ductless mini-split systems. We offer maintenance plans that can keep your equipment serviced on schedule while saving you money. Our team also specializes in HVAC zoning, whole-house fans, dehumidifiers, humidifiers, air purifiers, air scrubbers and UV lights. If you’d like to learn more about these products and services, call us today or contact us online.

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