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What Are the Major Parts of an Air Conditioner?

Your air conditioner is a critical component of a comfortable home in Los Angeles. When it stops operating effectively, it can cause panic and a bit of anxiety. These emotions are often caused by a lack of knowledge about your air conditioning system.

Take the mystery out of the process and arm yourself with the basic knowledge of how your system works and the parts it contains. This will help you feel more comfortable talking with a repair technician and give you some peace of mind in trusting the recommended repairs.

Making Sense of the Refrigeration Mystery

For some, the operation of an air conditioner seems fairly magical. The system turns on, and within minutes, you have cold air flowing from your vents.

The reality is it is an elegantly simple system that does two things: circulates air and refrigerant and regulates refrigerant pressure. What the system is actually doing is transferring heat from inside your house to the air outside.

The refrigerant undergoes two press significant pressure changes, which allow it to absorb heat and transfer it outside. When the refrigerant reaches the indoor unit, the pressure drops, making it very cold. The cold refrigerant then absorbs the heat from the air and transports it to the outdoor unit.

As it enters this unit, the pressure is increased substantially, intensifying the heat and allowing it to transfer to the air. All of this heat transfer is made possible by air circulating through the system.

All the Things You May Notice With a Problem

When your unit begins to have an issue, the symptoms may be nearly imperceptible. However, left uncorrected, you will inevitably begin to take notice. Nearly all of the problems will be accompanied by some common symptoms, with a few that are very specific to the faulty part.

Most people start by noticing either a lack of airflow through their vents or warmer air coming out when the system is running. Both of these circumstances can be caused by a faulty component, the system needing to be cleaned, or a lack of refrigerant in the unit.

If the problem persists over several months without detection, you will likely notice your energy bills creeping up. This is caused by the equipment having to run longer and work harder due to reduced efficiency.

You may also notice an increase in your indoor humidity level. This is caused by the system not drawing as much from the air, indicating either a lack of air circulating or the refrigerant not getting as cold.

The Compressor

The compressor is the part of the system that drives up the refrigerant pressure. This component sits in the condensing unit outside before the condensing coil. It is more prone to breaking or burning out because of the pressure it creates.

If the system has a refrigerant leak, it can cause the compressor to burn out. If this happens, it will need to be replaced, which means looking at the age and condition of your entire unit.

In addition to the symptoms already discussed, a failing compressor may bring a few others you may notice. The most obvious may be it tripping the circuit breaker tied to your air conditioning unit.

You may notice some rather loud and unusual sounds as well. These can include a growling, ratting, clattering, or even a screeching sound. If you suspect a problem like this, turn off your system and call for service.

The Condensing Coil

The condensing coil transfers the heat absorbed by the refrigerant to the outside air. Considering it has air constantly flowing through it, it is prone to getting clogged with dirt and debris. To keep it working well, it should be carefully cleaned during your regular spring maintenance.

The condensing coil is also a bit delicate and may develop a refrigerant leak over time. If this happens, you may notice a hissing or screaming sound coming from outside. If you hear this, shut off your system and contact a repair technician.

The Condensing Fan

Along with the condensing coil is a condensing fan. When this runs, it draws air in through the condensing coil, and then vents it out through the top of the system.

These fans are prone to some minor issues that are very easily rectified if caught early. Over time, the fan blades may loosen a little bit and can easily be tightened down again. If this is the case, you may notice a rattling or whirring sound.

The motor itself may burn out as well and can be replaced if the rest of the unit is still in good working order. A bad fan may give you a rattling or screeching sound. You may also notice the fan turning slower than usual or failing to turn on at all.

The Evaporator Coil

Inside of your house is the evaporator coil, which is the low-pressure side of the system. Just before the evaporator coil, the refrigerant passes through an expansion valve. This restricts how much refrigerant can go into the coil, quickly dropping the pressure and making it very cold.

Just like the condensing coil, this can develop a refrigerant leak or get clogged from contaminants from the air flowing through it. This should also be cleaned during your routine maintenance visit.

The Blower Fan

Both your heating and cooling system are dependent on circulating air through your home, and the blower fan makes it happen. Also known as the circulating fan, it draws air in through the intake, through the filter, and forces it through the coil and back out into the house.

Because it runs whenever any part of the HVAC system is on, it can get clogged with dust and dirt. It also has a tendency to become off-balance. The balance should be checked and the fan cleaned during routine maintenance.

If the balance is off, it will add strain to the motor and can cause it to burn out. If it is on its way out, you may notice a rattling or screeching sound as well.

Do Not Forget the Controls

Aside from the primary parts, your air conditioner has several smaller components that may go bad. The two most likely to have a problem are the capacitor and contactor. Both of these help control the compressor.

The capacitor stores a high-voltage charge to start the compressor when the system cycles on. The contactor acts as the switch to initiate the cycle. If the capacitor has a problem, you will likely hear a loud buzzing or humming sound. If the contactor goes bad, you will likely hear repetitive clicking or a chattering sound.

If one part of your system has a problem, it puts additional strain on the entire unit. This increases repair costs and shortens the service life of your equipment. JW Plumbing, Heating and Air has offered expert air conditioning repair and maintenance services to those living in and around La Puente for over a decade. Our team also provides expert heating and cooling installation, heating maintenance and repair, and a full range of plumbing services. Call today to schedule a visit from one of our expert air conditioning technicians.