To keep our homes comfortable throughout the entire year, we rely on our heating, ventilation, and air conditioning (HVAC) systems. When these systems are working efficiently, everyone is happy no matter what the weather is doing outdoors. Under normal operating conditions, you may hear some minor noises or air whooshing from a vent. But, there are seven HVAC sounds that cannot be ignored because they are a warning that something is wrong.

1.  Constant or Intermittent Clicking Noises

If the heating and cooling system is clicking constantly or when the equipment is starting up and shutting down, there are a couple of possible causes. These are both related to the electrical control systems. First, there may be a thermostat problem and it may be possible to fix the unit with some cleaning or a battery change. Next, the source of the clicking may be a faulty electrical relay that may need a repair or replacement. Dealing with electrical problems with no relevant HVAC engineering experience is not recommended. It’s easy for a DIY enthusiast to cause damage that’s expensive to repair and the risk of electrocution is high.

2.  A Constant Hissing Sound

When the HVAC system hisses it may indicate that there is a leak somewhere in the refrigerant line. Another possible cause is a compressor pressure that’s set too high or an internal valve leak. The hissing noise may continue even when the equipment is not running because the refrigerant is kept under pressure. When the AC system is run without sufficient refrigerant, it will be less energy efficient and the performance degrades. Locating and fixing a refrigerant leak can be tricky without HVAC training and experience. If the wrong refrigerant is used, it can affect the entire cooling system. Checking the refrigerant levels is included in an annual service visit and now is the ideal time to schedule some essential maintenance.

3.  Vibrating or Humming Noises

A humming noise may indicate that your compressor unit is being overworked or that the blower motor unit is failing. The vibrating sound or feeling can mean that the motor has become unbalanced or that some components are loose. Generally speaking, the louder these noises are the worse the problem is and these problems only get worse over time. Ignoring these sounds is a bad idea because more extensive problems cost more to fix. Overworked HVAC equipment also uses more energy which can drive up the utility bills.

4.  Rattling, Thumping, and Banging Sounds

These sounds are typically an indicator that there is something loose in the blower or motor. If the banging sound is really loud, there may be a component that was loose, but it’s now broken off entirely. The loose part may be moving around in the housing where it can cause damage to other components. If this situation continues, the resulting damage will be more expensive to fix and early intervention is recommended. If you can hear these noises in your HVAC system, contact a local heating and cooling specialist.

5.  Buzzing Noises

There are a number of possible causes of a buzzing noise in your HVAC system, including trapped debris, a loose fan motor, a dirty air filter, loose components, and a refrigerant leak. The easiest problem to fix with no HVAC training is the air filter. If you can’t remember when it was changed, go ahead and do that now. Changing the air filter regularly can prevent many potential problems and the full instructions are in the owner’s manual for your HVAC system. If the air filter change didn’t fix the problem, it’s time to contact an HVAC technician for an expert diagnosis.

6.  Grinding Sounds

If you can hear a grinding sound, it may be a warning that the compressor unit is starting to fail. As the pistons go out of alignment, they can come into contact with other metal surfaces. This will only get worse as time progresses and a new compressor unit installation may be necessary.

7.  Screeching and Squealing Noises

Another pair of noises that are related to mechanical component problems are screeching and squealing. Some typical problems may include motor bearing issues, a bad or failing belt, and a failing blower motor. If the belt is squealing, an adjustment to the tension may fix the problem in the same way as a fan belt on your car. But, if the belt is ignored, it will eventually break and the entire blower unit will stop working. The blower unit pushes the treated air throughout the home and if it isn’t working, the system will not work correctly. These noises are a sure sign that your HVAC system needs some essential maintenance.

The Importance of Regular HVAC Maintenance

As you can see, the sounds that we can hear emanating from our HVAC systems can give us some clues on the potential causes. But, it’s possible to avoid or mitigate the risks of a problem in your system with regular maintenance. A local professional HVAC technician will carry out a number of checks and tests to ensure that everything is working as intended. It’s important to understand that poorly maintained equipment tends to lack performance and energy efficiency. If your HVAC system is not receiving regular essential maintenance, it will cost more to run and your indoor comfort levels will suffer. Another important consideration is that poorly maintained systems tend to have a shorter lifespan which will lead to an earlier than expected replacement.

The Best Time for HVAC Maintenance

The heating system should be inspected at least one month before the heating season begins. The AC system needs to be checked at least one month prior to the start of the cooling season. Why? Well, the heating and cooling systems have not been used for a while and they can act erratically when they are started for the first time in months. The HVAC system needs to be ready for use when the weather conditions change. HVAC engineers are in-demand when the weather turns colder or hotter because of failures. The best time to get your system checked is before you need them to ensure that you’re prepared for the season ahead.

If you want to schedule some essential maintenance for your heating and cooling system, contact your local HVAC specialist today.