10 Most Common HVAC Problems and How to Troubleshoot Them


Regular inspections and maintenance can dramatically increase the lifespan of your HVAC unit. That being said, here are the 10 most common HVAC problems, and some tips on how to troubleshoot them.

Lack of Maintenance

If you neglect your HVAC unit, many problems can easily arise. Regular maintenance and inspections can help prevent problems before they get too bad.

More often than not, the lack of maintenance is the root cause of many HVAC problems, simply because the problem was not caught early on. You can easily call your HVAC company and set up an inspection to prevent problems from occurring later on down the road.

Dirty Filters

Dirty air filters can result in low airflow. This makes the HVAC unit have to work even harder to cool the room down. When the unit has to work harder, it is more susceptible to overheating. A unit that overheats will shut off.

You should regularly check and change your air filter to extend the life of your HVAC unit. Depending on the quality of your air, you should change the filter every one to three months. Discover more solutions at Victorville HVAC here.


Ignition or Pilot Problems

Your HVAC unit might have ignition or pilot problems, in which case, you should call in a trained service technician to evaluate the unit. It could be a dangerous problem because of the risks that come with high voltage and natural gas.

Problems might include a damaged flame sensor, a dirty pilot, or burners, and can result in short-cycling, furnace lockout, delayed ignition of burners, and pilot outage. A gas supply problem, or excess wear and tear on the ignition component, might also be the culprit.

Malfunctioning Thermostat

Luckily, you can solve this yourself. You might just need to replace the thermostat's batteries or adjust how it is set. You can reference the owner's manual and review the operating instructions. Do this before you hire a technician to check it out. If you still cannot figure it out, you should call to have it inspected.

Mechanical Wear and Tear

Your HVAC unit has mechanical components like bearings and belts. Over time, the wear and tear can cause damage that results in a malfunctioning air conditioner unit.

If these mechanical components are not inspected, the HVAC unit might overheat, have low airflow, or not heat up properly. A trained technician can come in to inspect the parts and oil them if need be.

Strange Furnace Noises

If your HVAC unit is making funny noises, you should call somebody in to inspect the unit. Sometimes these noises can be signs of a more serious problem. If the bearings in the blower motor or inducer motor are failing, you might hear a whining or squealing noise. In order to avoid furnace failure, you would have to replace the motor.

You may also hear other noises, which could be because the airflow is somehow stricter, or the burners are dirty. It is best to catch the problem before it is too late by calling a service technician to check out the potential cause of the noise.

Tripped Breakers or Blown Fuses

Most times, a tripped breaker or blown fuse is caused by something that is blocking airflow to your system. Low airflow results in the blower having to work harder than normal. This overworking causes breaker to the tripped.

As mentioned previously, low airflow might be caused by a dirty air filter, dirty coils, or blocked ducts.

Before you reset your breaker, replace the filter. If the problem happens again, call a service technician who can help figure out why the breaker keeps tripping. It could be due to a malfunctioning furnace, or your breaker might be having its own problems.

Dirty Evaporator Coils or Condenser

If you have been neglecting your HVAC unit, you might have dirty evaporator coils and a dirty condenser (learn more here). This would mean your unit is not going to cool near as well. Your coils can get dirty if dirt and debris enter the system. This will cause the system to wear out a lot more quickly. You should turn off the unit, then hose off the outdoor coil. If the furnace filters are not regularly cleaned, the indoor coil can get dirty, reducing the furnace and air conditioner's efficiency level. This will make the unit work harder.

If the coils are very dirty, you need to call a service technician.

Blower Runs Continuously

If your fan is running continuously, you should check that the thermostat is not set to the fan position. This will make your fan run. If the thermostat is normal, then you can check one other thing. The furnace has a fan relay used to turn on the blower when the heat is needed.

The blower will not shut off if the relay sticks. It could be that the furnace's safety was activated, resulting in the fan coming on to cool the unit down. You should call a technician to evaluate the problem. They can try to reset the limit or safety. Chances are, there is a root problem with your unit that the technician will be able to find.

Water Leaks

Your unit has drain pipes to help the condensation properly drain. Sometimes, these pipes can get cracked or clogged. You should try to keep these pipes clean by routinely pouring hydrogen peroxide down the pipes.

The unit might also be having issues with the collector box, evaporator drain pan, or heat exchanger. If you cannot seem to figure it out, go ahead and call the service technician.


The best way you can troubleshoot the most common air conditioner problems is by having the air conditioner regularly inspected. It will end up saving you a lot of time, money, energy, and discomfort later on down the road.

(Visited 511 times, 1 visits today)