woman hot from broken A/C

The Most Common AC Problems Homeowners Face

The Most Common AC Problems Homeowners Face

Is your AC unit not cooling the room as it should be? Are you having air conditioning problems with your HVAC unit? Are you looking for more information about these AC problems? Well, you came to the right place. Three-quarters of all US homes have air conditioners. This means every day, AC units are breaking down due to an array of air conditioning problems. Read further and gain some knowledge on the causes and/or solutions to these problems.

1. Frozen Coil

This is one of the most common air conditioner problems. There are many reasons that could cause a frozen coil. The reasons could range from low refrigerant levels to mechanical failures.

We’ll start with the low refrigerant issue. Inside the system, itself is low pressure. Even if there is less refrigerant in the system, the unit is still expanding the same amount of low pressure. More expansions cause a cooler temperature.

As the evaporator coil of your AC unit drops below freezing, the moisture in the air will freeze upon contact with your coil.

Another reason for AC units to get frozen coils is the outside temperature. Air conditioners need to function in a specific temperature range. When the air outside goes below 62º F, the pressure inside will drop and cause a frozen coil.

Mechanical failures include kinks in refrigerant lines, blower fans or clogged filter dryers. You can fix these problems yourself to save money on air conditioning repairs.

2. When the Outside Fan Isn’t Functioning

The outside fan is the one responsible for conveying heat from your unit to the outside air. If you don’t hear the outdoor unit’s compressor working, check if the fan is spinning. And even if you hear the outdoor unit’s compressor working, check your outside fan.

There are two possible scenarios for your AC problems. If the compressor works but the fan isn’t spinning, you could have a bad fan motor or bad start capacitor. There is also the possibility that both are not doing well.

If you can, try to get the fan to spin. Get a stick and start the spin yourself for a temporary solution. For a more permanent solution, call your AC electrician to fix it.

If both the compressor and the fan are not working, your outdoor unit isn’t getting enough power. There is also the possibility that the compressor contactor is defective. There is a process of fixing this.

Check your circuit breaker box if the outdoor unit’s breaker tripped. Turn off your AC at the thermostat and reset the breaker if that’s the case. If the breaker is not tripped, your compressor contactor may need replacing.

replacing A/C filter

3. Dirty Conditioning Coils and Filters

A clogged filter will restrict airflow and reduce your AC unit’s efficiency. This is why you should check and clean the filter on the regular. If you have a central AC system, change the filters.

If you’re unsure, refer to a manual or your manufacturer’s suggestions. Some AC units need filter replacements every three months. Others are reusable and need cleaning when they get dirty.

If you have pets in the house, you should perform regular maintenance on the filters of your AC unit. This applies even when you don’t have pets but you run your AC all day. In these cases, you may need to change or clean the filters at least once a month.

4. Drainage Problems

One of the most common air conditioner problems is drainage. If your AC unit leaks, there is an issue with its draining system. The condensate for home AC units should go outside through a pipe, not onto your walls or floors.

The common diagnosis is a clogged condensation drain. This is a simple problem to fix. All you need to do is inspect your drain line and clear it out of obstacles so it can drain well.

Hook a wet/dry vacuum to the outside end of the pipe to drain it. If you’re unsure about how you can go about this, get a professional. They can get the problem fixed right away and without the mess, using the right equipment for the job.

Always check for proper draining whenever the weather outside is humid. There is also the possibility that your air conditioner got mounted the wrong way. If it isn’t level, it won’t drain well.

5. Thermostat Sensor Problems

Air conditioning units have the ability to measure the temperature of air coming into its evaporative coil. The tool AC units use to gauge the air temperature is a thermostat sensor. You can find this sensor in room ACs behind the control panel.

An average July day’s temperature in St. Louis MO could reach up to 89.8º F. If your air conditioner cannot get the right temperature, it could malfunction. This could mean constant cycling or erratic behavior.

One common and fixable for this is when the sensor gets knocked out of position. With care, adjust its position by bending the wire that holds it in place. The thermostat sensor should be near the coil without touching it.

A/C serviceman

6. AC Won’t Turn Off

Even on a hot day, your AC should turn off on occasion. If it doesn’t do that, there may be a problem with the fan. To resolve this issue, turn the thermostat fan to the off position.

If it doesn’t stop, check for other factors. Check on the refrigerant levels and relay switches for any malfunctions. If you need to, call a professional to help you fix this issue.

7. Failing Capacitors

According to their design, most AC capacitors could last up to about 20 years. Still, many factors like heat exposure and voltage rating could cause them to wear out faster. Using undersized capacitors could also shorten their life span.

Capacitors are responsible for starting up your AC unit. Air conditioners need a lot of power to start up. Capacitors take up this tough task and eventual failure is no surprise.

The good thing about capacitors is they are inexpensive to get and replace. There are different types of capacitors which include the outside fan motor run capacitor, the start capacitor, and more. Among others, the most common capacitor to fail is the compressor motor run capacitor.

8. Compressor Won’t Turn On

You can find your AC unit’s compressor in the outdoor unit. If it isn’t turning on, it might not be getting enough power. It’s possible that a fuse blew or a breaker tripped.

It’s also possible that broken valves are the cause of the problem. Faulty or broken capacitors are common cases in many AC issues. Get a professional to check so you could get repairs instead of replacement, if possible.

Make sure that your compressor gets fixed right away. Constant stops and starts can damage the compressor. In time, it could put your entire AC unit out of commission.

9. Freon or Refrigerant Leaks

If you’re seeing reduced levels of refrigerant, there could be a leak in the system. This problem may arise when you need to recharge your conditioning system more often. Though it could also mean there is a problem with the refrigerant system, most of the time it’s a leak.

Another sign of a leak is when the vents aren’t blowing cool air. Put your hand by the vents and feel for the air that comes out. Is it as cool as it should be?

If you get close and hear hissing sounds coming from your unit, that’s another signal of a leak or other problems. If your electric bills increase due to inconsistent usage, that is another sign.

When it comes to leaks, a refill is a cheap solution but it isn’t the logical answer. Get to the heart of the problem first and fix the leak. Before you get a sealant and perhaps cause further damage, ask an HVAC professional first.

programming A/C thermostat

10. The Movie Star of AC Problems: Thermostat Issues

Movie writers for the horror genre love to use the thermostat as a popular problem. What can we say? Bringing the room temperature down makes the horror scenes more chilling.

Thermostat issues include short cycling, mismatching room temperatures, and more. One of the simplest problems is when the AC unit stops working and the thermostat doesn’t light up. This could be due to dead batteries, a tripped breaker, or blown fuse in your main electrical panel.

If a thermostat isn’t level or if it's dirty inside, it can trigger frequent short cycling. Another cause is an anticipator that did not get the right calibrations. You can lengthen the cooling cycle by moving the anticipator arm toward the marking for longer.

Move the arm in single-notch increments. Between adjustments, wait for the AC to complete a full cycle. If the problems are the latter, level the thermostat or clean it.

Fix These Common AC Problems Now

That’s it for our list of the most common AC problems that homeowners experience. While it is cheaper to DIY many of these, it’s also a risk if you have no knowledge of repairing AC systems. It’s still smarter to hire a professional to solve your problems.

Are you having heating and cooling problems with your HVAC unit? Are you in or near St. Louis, MO area? Feel free to visit our offices anytime.

You can also give us a call for emergency repairs and services.

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