Signs Your HVAC System is Faulty

Last updated on October 10, 2023

Heating, ventilation, and air conditioning (HVAC) systems provide homes and business establishments with extra comfort during the right climate. Homes can activate the air-conditioning during the hot summer months. Business establishments like restaurants can turn on the heating and ventilation during fall and winter. However, these systems aren’t perfect. There might come a time when malfunctions arise. Here are five warning signs to look into if you think your HVAC system is faulty.

No Cool Air Blowing

Many HVAC system owners despise it when the cooling system decides to malfunction or breakdown during hot days. At this time, drinking a cold beverage or activating the electric fan may not suffice to keep you and other people in the area feel refreshed.

If the temperature setting on your HVAC system says it should give you blasts of cold air, but it’s not, then it’s a sign that something’s wrong with the unit.

A lack of fresh air may mean that the HVAC system’s compressor is failing. You may need to call professional help. Experts can open the system to check if there’s anything wrong with the compressor. However, hot air blowing from the cooling unit may mean that you need to replace the AC compressor.

Weird Noises

hvac system

Many HVAC systems should have silent operations. So, if you start hearing funny or weird noises from the unit, parts may have fallen loose. The worst-case scenario in this regard is that there are specific parts that fell apart. A few sounds that indicate signs of machine damage include clunking, grinding, hissing, and rattling from the unit.

You can hypothesize the extent of the issue with the sound your HVAC makes. Here are a few examples:

  • Grinding – Something may be wrong with the air handler of the system and its bearings.
  • Hissing – The fan belt may be faulty. This part may need cleaning or replacement.
  • Rattling – Small parts within the unit may be loose.
  • Clunking – There may be something stuck in the cooling fan.

Remember, don’t attempt to open and troubleshoot the HVAC system if you don’t know what you’re doing. Leave the maintenance and repairs to the experts to avoid extra complications.

An Increase in Energy Bills

When your monthly energy bill arrives, does it show a spike in charges? If so, it may be because of problems regarding your HVAC system. Many machines work their best when they’re operating at maximum efficiency. If there are problems in the HVAC unit, the system may need to work harder to maintain normal operations. So, if the machine works harder, the more energy it consumes.

Decrease your energy bill by making sure your HVAC system is running smoothly. The increase in charges may not happen abruptly. Instead, the issues in the HVAC unit may start arriving at a specified period. Check your past utility bills to see when the increase in fees began. Then, contact an expert HVAC technician to help you isolate and repair the issue.  

A Foul Smell Around the Area

Is there a foul or rotten smell in your home or office even though you’ve already put out the trash? If so, then the smell may come from the faulty filter in your HVAC system.

Filters in HVAC units need cleaning or replacement over time. Dust, dirt, and other debris may attempt to get into the premises through the HVAC system. However, the filter should do an excellent job in keeping these things at bay. Still, the filter will become damaged or dirty with constant use.

At that point, you may consider learning how to change the filter. If you’re not confident in doing this task, it’s best to ask professionals to deal with the issue for you. Professional HVAC technicians also know where to get the right filtering unit compatible with the system in your establishment.

A Broken Thermostat


The central command for the HVAC system is the thermostat. Use it to control the cooling and heating features coming from the system. However, if the thermostat won’t turn on or it’s giving you a difficult time in operating the HVAC system, it may need more than a battery replacement.

Have a trained HVAC technician look into your unit’s thermostat to see the underlying cause. This component has intricate electrical components. One wrong move from a DIY operation without proper know-how may mean disaster for the entire system.

Once again, don’t attempt to handle the maintenance and repairs of your HVAC system if you don’t have proper knowledge and training in solving its issues. Don’t hesitate to call experts in this sector to take a look when there are signs of problems coming from the HVAC unit.  


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