You want to do the best job you can with your air conditioning system. Doing your best to avoid the most common problems with air conditioners is essential. No matter how cautious you are, AC problems in the home can still happen. It is important to diagnose and fix home AC issues as quickly as possible. This will prevent a cascade of other more expensive problems.
This summary outlines the most common AC problems in the home and provides tips on how to resolve them before you call an air conditioning contractor.
Diagnose and fix common home air conditioning problems:
Even new systems can have problems if they’re not installed or maintained correctly. If you are diagnosing AC problems in your home, keep an eye on these warning signs.
Home Air Conditioning Problem #1: Air conditioners that run constantly
Problem: Your AC runs constantly and cannot reach the temperature that you set. This can lead to an uncomfortable home temperature throughout the day, especially during summer. It also increases your energy bill.
There are many reasons why your AC unit may run continuously. You may have dirty air filters that make your system work harder in order to reach the desired temperature. Or you may have a leaky coolant which reduces the unit’s cooling ability.
How to check: Set your thermostat 1 to 2 degrees below the current temperature and time how long your AC unit takes to shut off. It should usually shut down in a few hours. Your AC unit will run continuously if it does not shut off correctly.
Fixing the AC problem at home can be as easy as changing your air filter, cleaning out the exterior air box and setting the right temperature during the day. If none of these solutions seems to help, you might want to call an HVAC professional who can run a diagnostic to check for leaks and replace any parts that need to be replaced.
Home Air Conditioning Problem #2 – AC Unit Doesn’t Turn On
The AC unit will not turn on even after changing thermostat settings or turning on the thermostat.
Possible causes: A circuit breaker could be tripping. A thermostat that is not communicating with the AC could also be the problem.
How to check: Reset the circuit breakers. The thermostat may be to blame if the AC won’t start.
Fixing this AC Problem at Home: If the problem was with the circuit breaker, the problem could be resolved. You may need a licensed electrical contractor to check the wiring and circuit breaker to ensure it is not overloaded. You can install a new thermostat or ask an HVAC technician to look at the unit if the thermostat appears to be the issue.
Home Air Conditioning Problem #3: Air is flowing but it doesn’t seem “conditioned”
The Problem: If the AC unit just cycles air through the vents but it’s not hot or cold, then the unit doesn’t appear to be “conditioned.”
This could happen for a number of reasons. This can be caused by a dirty coil or a smaller HVAC system.
How to check: Check when the problem occurs. If it happens in summer, during the daytime, the AC may not be able to compensate for the high temperatures outside. If the problem persists throughout the day, the issue could be mechanical or maintenance related.
How to Fix this Home AC Problem. The system may not be able to handle the heat if it occurs at the hottest time of the day. This issue may require that you replace your existing system with one that has variable speeds. If you do not want to completely replace your HVAC system, weatherize the house to reduce the work that it has to perform. The HVAC system should be checked if the problem persists throughout the day. This will help determine the best solution.
Home Air Conditioning Problem #4: AC Blowing Hot Air
Problem: AC blows out air, but it is hot air.
The first thing that comes to your mind is a refrigerant leak. There are a number of possible reasons why this could be happening. Dirty air filters can lead to a dirty evaporator and condenser coils on the outdoor unit.
Check the thermostat first to see if it has been accidentally set on heat. Inspect the air filter if that’s not the issue. If the air filter is dirty, you should also check the evaporator. Check the outdoor unit to see if the air filter appears clean to determine if there is adequate airflow.
How to Fix this Home AC Problem: You may only need to give it a good cleaning. The problem could be resolved by replacing the air filter, cleaning the dirty evaporator, and clearing the debris in the unit and the vegetation surrounding it. If none of these things works, you may need to hire a technician to top up the refrigerant.
Home Air Conditioning Problem #5: AC Unit Stops and Starts Constantly
Problem: The system has a short cycle, which means it turns on and off continuously for less than 15-minute periods at a given time.
Short cycling can be caused by a number of things. A dirty air filter or even a small leak of refrigerant can cause this. The problem could also be complex, such as the AC being too powerful to work with the electrical wiring. The AC system is either stuck in its startup cycle or the blower motor is being overloaded.
First, you need to check your air filter. Check the thermostat next to ensure it is working correctly. If neither of these seems to be the problem, then it is most likely a leak in the refrigerant.
Replace the thermostat or air filter if they are the cause of the problem. A refrigerant problem will require an HVAC expert to fix it. You can also determine whether your HVAC system is sized appropriately for your home.
Home Air Conditioning Problem #6: AC Unit Trips Circuit Breaker
Problem: When the AC is turned on, a circuit breaker trips.
Circuit breaker tripping can be a good sign, as it helps prevent electrical fires. It’s an indication that either a short-circuit is occurring, the circuit breaker is bad or the refrigerant is not being pumped out.
Check your air filter again. The system can work harder if the air filter is heavily clogged. Condenser coils that are dirty can also contribute to the problem. It’s likely that the issue is not dirty equipment but a mechanical or electric problem. A professional should inspect it.
How to Fix this Home AC Problem. Homeowners are able to replace the air filter and clean their condenser coils. Fixes to the wiring and circuit breaker system are best left to a licensed electrician. HVAC contractors are needed to fix refrigerant problems.
Home Air Conditioning Problem #7: Central Air Smells Bad or Off
Problem: The air coming out of the air conditioner is stale or smells off in some way.
There are several causes of foul-smelling air. Common causes include drainage issues leading to standing water, fluid leaks that cause fumes, a short-circuiting fan motor, dead animals trapped in air ducts and mildew in the AC system.
The smell is often the best indicator of the problem. The smell of rotten eggs suggests that there is a dead animal. A gas or exhaust smell indicates a fluid spill. The all-too-familiar mildew odour will also give you away.
How to Fix this Home AC Problem When smells are a problem, professional cleaning is often the solution. It may be necessary to find a leak in the system and patch it.
Home Air Conditioning Problem #8: AC Unit Is Causing Water Leaks from Air Vents
Water is leaking from the air vents. Water leaks can damage the air conditioning system and cause serious problems to ceilings, walls and floors.
You may see moisture near your vents due to a variety of reasons. This could be due to inadequate insulation around the ducts, a frozen evaporator, dirty air filters, or refrigerant leaks.
How to Check: It is important to determine where the moisture comes from. Check your air filter first to see if is dirty or wet. Check the insulation of your ducts. When the airflow or air cooling is poor, the humidity in the air will be caused by refrigerant leaking. Check the condensate drainage line and evaporator. If the problem is primarily when the AC is off, the evaporator is most likely to be the culprit. The problem could be in the drain system if the outside condenser drain pan is full.
How to Fix this Home AC Problem: It’s not necessary to replace the air filter or improve the insulation surrounding the ducts to fix the problem. If the problem appears to be in the condensate drainage line, refrigerant or evaporator, then you will need to contact an AC technician.
Home Air Conditioning Problem #9: Water Leaks From AC Condenser Outlet On Exterior of House
It’s important to identify the problem if you notice water coming from the AC condenser pipe outside the home. It’s an issue that should be dealt with immediately as it could indicate serious air conditioner issues and cause damage to your house.
Small amounts of condensation are normal, particularly during hot summer days. If there is a lot of leakage, the most likely cause is a condenser pipe that’s clogged. Another simple issue could be a cracked pan for condensate or a dirty air filter. The AC system may have been installed incorrectly or is not draining correctly.
How to check: First, determine how much water has leaked out. It’s not a good sign if there’s more water than a small pool. The next step is to check the pipes that are leaking water. Leakages of water during operation are normal, but a continuous leak is not.
How to Fix this Home AC Problem. Replace your dirty air filter first. Then, if that fixes the problem, then great! If the problem persists, you will need to call an AC professional who can clear out the clog in the condensate drain line, replace the broken pan or reinstall your equipment.
Home Air Conditioning Problem #10 – Air Box Fan Isn’t Turning On
Problem: The AC airbox fan will not turn on, even though the thermostat indicates that it is running. The first thing you’ll notice is that the AC system may appear to be running, but it doesn’t cool down inside as normal.
Possible causes: The problem usually is a major one when the outside unit stops working. The motor of the outdoor unit could have burned out, or there may be bad capacitors. Or the power supply might not be adequate. There could be an easy reason for the outdoor unit not working. For example, a tripped breaker.
Check the box fan outside and make sure the emergency shutoff switch is not engaged. You may hear the electrical unit running but not feel or see the fan. This will let you know if the AC air box doesn’t work. You’ll hopefully find a blown fuse or circuit breaker on the electrical panel. Try resetting your AC unit if it doesn’t work. If your outdoor unit doesn’t work, something is wrong inside. A technician should check it out.
While you are examining the problem, you can try some of the DIY fixes listed above. When these do not work, a technician will be needed to test the system in order to find the issue. It will be necessary to replace all bad capacitors, contactor problems, and blown-out motors. A licensed electrician may be required to address inadequate power supplies.
Home Air Conditioning Problem #11: Dust Builds Up Quickly on Surface
The issue: You have just swept your house and now you notice a thick layer of dust covering everything.
The most common cause of this problem in a home AC is a dirty filter. It could be that there are leaks in ductwork, allowing dust to circulate throughout the AC system.
Check the Air Filter: As with so many other AC problems that are common in homes, the first step is to check the air filters. You can tell if it’s dirty. If the air filter has been cleaned and yet dust is still settling within a few days, you should check for leaks in the ductwork. If dust is accumulating around the vents, there may be a leak in your ductwork that allows dirt and other debris to enter the HVAC system.
It is easy to fix this problem. The problem should be resolved once you change your air filter. Air contaminants are now captured. Leaky ducts, however, may require the expertise of a professional equipped to inspect the ductwork. You can repair small leaks with HVAC aluminum foil seal tape. For larger leaks, you will need to call a professional.
Home Air Conditioning Problem #12 – Air Blows Coldest in One Room
Problem: Have you noticed that one room is colder than the others? A common AC issue is blowing super cold air into just one room or a portion of your house.
Possible Causes: The problem can be caused by three factors: the way the vents are positioned and set up, leaky or unbalanced air ducts and inadequate insulation.
How to Check: First, check that the registers and vents are open in all rooms. Check the dampers and make sure they are not closed. Inspect the air filter, if necessary. If possible, check the insulation and ductwork to make sure they are in good condition and adequate.
How to Fix this Home AC Problem. The key to solving this problem is to balance out the airflow so that it circulates evenly throughout your home. HVAC balancing, also called zoning, is the process that involves a thorough assessment of how vents are positioned and how air moves in the home. HVAC zoning is the division of an air conditioning system into zones. This is an excellent idea for homes that have multiple levels and large square footage. You can balance the airflow by adjusting the dampers on the ductwork. You can also open and close the registers to alter how air enters each room. You may need to add insulation and fix the ductwork in some areas of your home if the inspection is successful.
Home Air Conditioning Problem #13 – Air Blown Smells As If It’s Burning
Problem: If the air coming from the vents has a burnt smell, then something is wrong. You may notice that the air is warmer than normal.
The most likely cause is that dust and debris have built up inside the AC unit and this is causing it to turn on the heater instead of the AC. The dust could be burning off. A dirty air filter is also a possible cause. Another possible cause is an overheated motor. Burning electrical components, though rare, could also be the culprit.
How to Check: You’ll need to check your air filter again to determine if you should replace it. If the air filters look good, it is likely that the motor or electrical component has failed. These issues need to be inspected by an HVAC contractor in Knoxville TN.
How to Fix this Home Air Conditioning. A homeowner can change the air filter easily, but other issues require a professional to address. It may be necessary to replace one component, such as a capacitor, or even the entire motor.
Air Conditioning Problem #14 – Increased monthly energy bill
Checking your bank account, you notice that the utility bill has increased significantly. This is not a problem with the HVAC system but it does indicate that it’s time for you to diagnose home AC issues. If your energy bill increases but you haven’t seen any change in usage, this could be a sign that something is wrong.
If your energy bill suddenly spikes, there are many possible causes. There are many possible causes, from a dirty filter to improperly-installed ductwork or low refrigerant. The bottom line is that something could be causing the system to work harder than usual.
How to Check: To check the air filter, you can perform a general HVAC examination yourself. The ENERGY STAR HVAC Maintenance Checklist is a great resource to cover the major components.
Fixing this AC problem at home depends on the cause. The fix could be as easy as changing the air filter or as complicated as installing a brand-new system.
Call J.C.’s Heating and Air now if you need help installing, repairing, or maintaining your air conditioning unit.
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