Common Reasons for HVAC Noise

January 20, 2023
Nacogdoches, TX AC Repair

Having an HVAC system in your home is a necessity for keeping your family comfortable throughout the entire year. However, just like any other system in your home, your HVAC system may experience some issues from time to time. If you hear any of the following noises, it’s important that you address them sooner rather than later.


When you start to hear a rattling noise coming from your HVAC system, it’s an indication that there’s something stuck inside of it. If it’s happening to your outdoor unit, it’s highly likely that a piece of debris, like a twig, is stuck in the fan blades. If it’s happening at your inside unit, it could be an indication that one of the bolts or other pieces of hardware is loose. Either way, you’ll want to turn off your HVAC system and contact a professional to identify the source of the rattling and fix it. Letting the problem persist can end up resulting in more damage to your system’s components.


If you start to hear a hissing noise coming from your HVAC system, then it’s an indication that you have an air leak somewhere. If it’s coming from your air conditioning unit, it’s best to shut it down and contact a licensed professional, as refrigerant can be very dangerous. If you notice this hissing sound only at certain parts of your home, it may be that there are leaks in the ductwork in those areas. To fix the hissing, you’ll need to have a professional repair the ductwork where you hear the hissing noises.


A popping sound that comes from their ductwork is a common noise that concerns many homeowners. This typically occurs when your heating or cooling system starts up for the first time. While this sound is definitely abnormal, it’s not a large cause for concern. The popping sounds simply come from the metal ducting expanding and contracting due to temperature differences. You should hear the popping go away after your system has been running for a short while.


One unusual sound that will be likely to get your attention as soon as it happens is a high pitch whistling noise. This can be an indication of a couple of different problems. First and most common, this whistling noise can indicate that your AC compressor is failing. This noise can also indicate that there’s a dangerous refrigerant leak in the high-pressure line. Either way, you should shut off your HVAC system. If the whistling goes away, then it was likely your AC compressor. If it doesn’t, then it’s probably your refrigerant.


Over time, all the internal components of your HVAC system will wear out. If you start to hear a squealing noise that becomes more prominent over a period of days, it’s likely that your fan belt is reaching the end of its life span. In most cases, you can have an HVAC professional replace the belt. On some older units, your furnace may need to be lubricated to reduce its squealing noise.

Frequent Clicking

It’s completely normal for your HVAC system to click when it first starts running. In fact, this is a useful noise to help alert you when your heating system is kicking on and off. However, if you notice that your system is frequently clicking, it could be an indication that you have a faulty ignition system. It’s important to address this problem sooner rather than later to help prevent any further damage from happening inside your HVAC system.


One noise that will be sure to get your attention is a booming sound. This will happen when your furnace tries to light but does not have success doing so. As your heating system continues to try to start, gas will build up inside the combustion chamber. Eventually, when your system does light, it will create a booming noise due to the increased amount of gas that lights. If you experience this booming sound, it’s time to call in a professional to have your system cleaned so that you don’t have this problem going into the future.

Reliable HVAC Services

Nacogdoches Sheet Metal, Plumbing & Air Conditioning, LTD. provides reliable HVAC services throughout the entire Nacogdoches, TX and surrounding communities. We can also assist with all of your sheet metal fabrication, duct cleaning, plumbing, and indoor air quality needs. Contact Nacogdoches Sheet Metal, Plumbing & Air Conditioning, LTD. today to get the professional help that you need.