June 16, 2021
Central Air Conditioner in Sacramento, CA

The summers in northern California are an amazing experience but still need the relief of an air conditioner. However, keeping that air conditioner running can seem stressful when you don’t understand how it works. Learn how your central air keeps your home cool, and what you need to know to get the most from it.

Circulating Air

The first thing to know about any HVAC system is that it depends on its ability to circulate air. But the circulation doesn’t only include what flows through your system.

Your circulating fan draws air in through the return vents, conditions it through the evaporator coil, and pushes it back out. This process creates high pressure at the output vents and low pressure at the return vents. The pressure difference causes the air to move throughout your home.

Closed or blocked vents prevent your system from creating the correct pressure difference. Without this airflow, your air not only stagnates, but it becomes ineffective in cooling your home. Keep your vents open with at least a couple of inches of clearance to allow air circulation.

Likewise, your HVAC system must be able to get the air in as well. The filter collects airborne contaminants as air flows through it, eventually causing a clog. The smaller particles settle on the evaporator coil and circulating fan, further restricting the air.

It’s important to keep up on your system maintenance to prevent these airflow restrictions. Not only do they inhibit cooling, but also add tremendous strain, leading to repairs and shorter service life.

Regulating Refrigerant

Most people recognize the refrigerant in an air conditioner as what cools the air. It does this by absorbing the heat from the air circulating through the system. It then vents it to the air outside through the condensing coil.

In order to absorb the heat, the refrigerant must be cooler than the air circulating through the system. Refrigerant gets cold when the pressure decreases and gets hot when the pressure increases.

As the refrigerant enters the evaporator coil, the expansion valve restricts the flow, causing the pressure and temperature to drop. Before it enters the condensing coil, the compressor condenses the refrigerant, driving up the pressure. As long as the system continues to regulate the pressure properly, the system continues to run perfectly.

The refrigerant will not pressurize correctly if the compressor doesn’t work properly or if the refrigerant level is low. Low refrigerant will also cause freezing in the system, leading to additional damage.

Getting The Size Right

Air conditioners have different sizes, and it’s important to get the right one for your home. Air conditioning size refers to the cooling capacity, which is measured in BTUs. This stands for British thermal units and is the amount of heat needed to raise one pound of water by one degree Fahrenheit.

If your air conditioner is too small for your space, it will run continuously while struggling to achieve the set temperature. This leads to increased utility costs and a shortened service life for your system.

While it may seem like a higher capacity may be advantageous because it’ll cool more, it actually inhibits proper operation. Larger systems use more energy to run and cost more to install, so you will have higher installation and operational costs.

On top of that, a larger system runs shorter cycles, but those short cycles run more frequently because of less actual air circulation. This leads to more starting, which is the most strenuous part of the run cycle and uses the most energy. In the end, larger units will leave your home less comfortable, while you pay substantially more for them.

What Happens As It Gets Older

The average air conditioner lasts between 10 and 15 years when it is properly maintained. That means you can anticipate when it will need replacing and plan accordingly. You will experience a couple of normal problems as your system ages.

First, your system will have components wear out. The most common to wear out are the condensing capacitor, contractor, and circulating fan motor.

In addition to some parts wearing out, your system will naturally start losing some efficiency. Degradation in the circulating fan’s performance, airflow restrictions, and leaks in your ductwork cause the system to lose efficiency.

What Kind of Maintenance Is Required?

As already mentioned, your system requires some routine maintenance if you want it to last the expected service life. Some maintenance you can do, while most of it you will want to have a professional technician perform.

The easiest bit of maintenance is changing your air filters periodically to keep the air flowing freely. Most air filters should be changed about once every 90 days. However, the specific air quality and filter type and size may make it different for your furnace.

Plan to check your filter as part of your monthly home maintenance to keep an eye on how quickly it clogs. While you have it out, plan to gently vacuum the intake side to help extend its usefulness.

Next, your system needs professional routine maintenance, which is usually performed in the spring for air conditioners. The goal of maintenance is to keep your system operating at peak efficiency and catching small problems early.

To do this, your technician will clean the circulating fan and condensing and evaporator coils. While working on the coils, the technician will also check for any obvious signs of a refrigerant leak.

They will also test your fan motors, tighten the mounting bolts, and lubricate the fan bearings. This helps reduce the wear from the vibration that fan motors experience during normal operation.

Finally, your technician will test the various components to ensure each is working within optimal parameters. If they find something suboptimal, you can repair it before causing more damage to your system.

Dealing With Problems

Air conditioners may experience some problems before the end of their service life that need repairing. Most commonly, you may have problems with the capacitor, contactor, or circulating fan motor.

If your compressor fails to start, and you hear a loud buzzing sound from outside, it may be the capacitor. If you notice the compressor starts and stops quickly, and you hear a chattering sound, it is likely the contractor going bad.

The circulating fan works year-round with both your air conditioner and heating system. When this burns out, you may notice it fails to start, or that you have very little airflow from your vents. You may also smell a mild burning odor or hear a squealing sound coming from your indoor unit.

Air conditioning repairs are best left to trained professionals with the right equipment. Due to the electrical current needed to run your unit, any work risks serious electrical shock if not performed correctly.

Furthermore, it is easy to cause a refrigerant leak if you attempt a repair with the wrong equipment or improper training. Once you have a leak, you are most likely looking at either extensive repairs or a new system.

Contact Your AC Professionals

People around Sacramento have turned to Gallagher's Plumbing, Heating and Air Conditioning since 1989 for heating and air conditioner installation, maintenance, and repair along with water heater services. Call to schedule your visit with one of our expert technicians today.

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