Why is my HVAC System Noisy?

Posted on March 14th, 2018 by carrolladmin

Before you read this article, please make sure you call us if your HVAC is makes any noise you don’t recognize.

HVAC noises coming from a large heating and cooling unit.

 

The majority of our residential customers have central forced air heating and cooling, and one of two heating ventilation and air conditioning (HVAC) equipment arrangements. The first is an electric heat pump that handles both heating and cooling functions. This is the most common HVAC system set up in newer homes. The second configuration is a furnace and air conditioner, each separately heating or cooling.

The best system for any home depends on the cost and efficiency of the equipment, yearly energy use, availability of energy sources, and the local cost for fuels like gas and oil. With that said, in most homes, it doesn’t matter so much the type of equipment. As long as it’s sized and installed properly for the house, it should cost-effectively provide indoor comfort.

Know your HVAC System

Do you know what types of equipment make up your home’s HVAC system? If not, you should familiarize yourself. It’s a good idea to understand the location and basics of your equipment if you ever need to troubleshoot an issue before calling a professional. 

Most HVAC systems are fairly reliable as long as they aren’t overdue for a replacement or lack routine preventative maintenance. However, whether it’s during heating or cooling season, problems do occur with no rhyme or reason. HVAC systems can experience many issues, like blown fuses, refrigerant leak, loose parts, worn condenser coils, and damaged thermostats

Related: Common issues with aging equipment

At Carroll Plumbing & Heating Inc., our technicians have seen it all and fixed it all, so none of these problems are tricky repairs for us—if your system isn’t working correctly, just give us a call!

Noisy Operation is Not Something to Ignore

One of the most common complaints we get from customers is in regards to a noisy HVAC system. It’s not out of the ordinary for a customer to tell us that their system has been making strange noises for a while, but they thought nothing of it. Knowing the difference between the normal noises from an unusual noise that suggests a problem can be difficult. This is why we encourage homeowners to understand their equipment, including how it sounds when it’s working correctly.

Some Noise Isn’t Cause for Alarm

One of the most common noises you’ll hear from your HVAC system is the quiet, continual hum of properly functioning equipment. When the system runs, you may hear the motor of the indoor unit in operation, depending on where it’s installed. The outdoor unit includes a fan and a motor, which will most certainly make more noise than indoor equipment.  

It’s also typical for a quiet swooshing sound to come from registers as air rushes through the vents.  

Lastly, a squeal or thump when the system cycles on and off isn’t cause for alarm, but it is an indicator you’re due for a tune-up.

Related: How important is preventative maintenance?

Identifying Unusual Noises

Indoor units – whether the air handler or furnace is reasonably typical complaints when it comes to noise. In many cases, it’s caused by a bad belt or bearing in the blower motor. Unusually noisy motors inside air handlers and furnaces make squealing, screeching, rattling, and/or banging noises when the equipment malfunctions. In most cases, these are inexpensive repairs—adding lubricant, tightening parts, and replacing belts. 

If you know how, you can do it yourself, or give us a call to come out and complete the maintenance needed. 

If you hear a clicking sound inside your home, it’s likely not your air handler or furnace, rather the thermostat. There is an audible click signifying communication between the thermostat and the capacitors when it’s time to activate it. Repeated clicking means there is a defective relay causing the system to timeout and fail when starting up. You should contact an HVAC specialist to complete the repair. 

Outdoor unit – regardless of a heat pump or air conditioner, a sudden loud rattle is usually due to a branch or other type of debris stuck inside the exhaust fan.  

Although there is a grate to protect against objects obstructing your fan, small twigs and debris can make its way inside. If you suspect something is stuck, immediately turn off power to the exterior unit and see if you notice any obstruction.

If you see bent metal, damage to moving parts, or anything else that doesn’t seem right, contact Carroll Plumbing & Heating Inc.  

Vents & registers – a soft rush of air is typical, but a higher noise level is cause for concern.  

An audible hiss could indicate damage to coolant lines, a coolant leak, or improperly sealed ductwork. More commonly, customers complain that air vents and registers make a high-pitched, vibrating type of sound. This can be caused by a lack of return air, which can occur because too many vents are closed off, or furniture is obstructing airflow. It’s also possible a more significant issue exists—undersized or improperly installed ductwork.

More Common HVAC Noises

Thumbing or clanking 

To hear these sounds means you could have a problem with your blower assembly. We recommend you turn off your HVAC system and call a professional to complete a diagnostic.

Popping 

When you hear a popping sound as you turn your system on and off, it’s usually not a sign of problems brewing. You can rest assured that ‘s just the ductwork expanding. 

Buzzing

A few culprits could cause a buzzing sound coming from your HVAC system. It could be simple like a few loose parts in your unit, or your motor could be going out. You want to schedule a diagnostic to determine the cause of the buzzing sound. 

HVAC systems can produce a wide range of noises—many are normal, but others are not. It’s always best to err on the side of caution when you suspect something isn’t right with your HVAC system because a minor problem can quickly turn into an expensive repair.

Learn More About Our HVAC Services

DOWNTOWN - FAN
DOWNTOWN - FAN
NORTHSIDE
NORTHSIDE
SOUTHSIDE
SOUTHSIDE
WEST END
WEST END
Carroll Plumbing & Heating came through for me in an emergency. I called for help when my home warranty company couldn't send out a plumber right away. I had a busted hot water tank in my attic and was leaking water through my ceiling. I had a real emergency and they came within 30 mins. The Techs got in my attic cut off the gas to the tank and water. Then they drained the water. It was a hard job due to the tight area in my attic. The were very professional and knowledgeable. The also wore their masks. I would recommend them to anyone. I give them an "A" plus. Thanks to them guys at Carroll.
Charmagne Richardson
Charmagne Richardson
Had a new kitchen sink installed today by Keith. Arrived on time, very professional and pleasant, A+ workmanship. Could not have been done better, and the cost was quite reasonable.
I had an issue with a boiler install (not done by Carroll). They came out, took a look, and had it working within 20 minutes. Highly recommend, especially Bruce. He's very knowledgable, friendly, and easy to work with.
Enzo Chiariello
Enzo Chiariello
I called them a few weeks ago for some issues in an newly purchased investment property (sink and shower not draining, water heater not working). Unfortunately the issue with the sink was more extensive than we thought but I appreciated that he cut to the chase and let me know up front. They have been incredibly flexible with scheduling since we have had to coordinate some other things in the process with contractors moving cabinets, etc. They are generally in and out without a trace which has been great, and I felt that the price was reasonable. I am pleased with them overall and plan to use them again for my investments and primary residence.
I have used Carroll’s for about 25 years, at two houses. They are quick to come, and always pleased with their work and service. Highly recommend!
M Borton
Called over holiday weekend w leaking sewage pipe. They advised cost would be high and suggested temporary water collection. Saved us money and earned our respect for their integrity. Made repair quickly after. Get service and workmanship.
Ben Hagen
Ben Hagen
Robert and Mike are great. Arrived on time and went right to work. I had another issue and they took the time to explain what I needed. I have more work to be done and plan to ask for them specifically.
Cat Momma
Cat Momma
Very reliable, knowledgeable, and courteous. We've done business with them for years and wouldn't call anyone else.
I have been a customer of Carroll Plumbing and Heating for over 30 years and would not go anywhere else.
Bill Fielden
Bill Fielden
I will never call anyone else again! They were so nice, super fast, and very efficient!!! Everyone from the receptionist to the dispatcher and the technicians. The manager even checked in on us!! Cannot say enough great things about this company!! Thank you so much!!
Jill Anderson
Jill Anderson
The guys from Carroll were prompt, professional, patient & reasonable. They diagnosed my problem, replaced the parts and were in & out within an hour. This was the first time I've use Carroll and I can guarantee there will be a second when the need arises.
Patrick Siewert
Patrick Siewert
Excellent Customer Service
Justin Bowman
Justin Bowman
Best plumbing, heating and cooling contractor in the metro area!
Jacob Ray
Jacob Ray
Excellent job and workmanship. We had an emergency issue that required a gas line replacement. They were on the spot, courteous, and professional. We never had to go a night without heat or hot water. I'll go back to this place for all of my heating and plumbing needs. Dustin is a great plumber and Bruce runs a tight shop -- personally making sure customers are happy.
Matt Gardner
Matt Gardner
Great service! I called them late Monday and they were at my house Tuesday morning the next day. Always have had a great experience with Carroll. Highly recommend them!
Randy Sklar
Randy Sklar
I called this morning due to my heat pump not turning on, they fit me into their busy schedule, great service, technician was extremely knowledgeable and friendly, definitely will be using them in the future for some plumbing needs, highly recommend them
Had an extremely poor experience with another plumbing company in Richmond and was sick of dealing with trying to get in contact with their "managers." My roommate found Carroll online and I called for an appointment. The receptionist that answered was very nice and seemed to know exactly who to send me to for immediate assistance, rather than have me play phone tag with multiple departments.A kind man named Bruce was over to diagnose the issue, walk me through the repair and how our aged heating system worked, and think of a creative solution that saved me over $500 off the total bill with a fair invoice that detailed the work demands and parts used--all in the same day. They may be a little pricey, but I was incredibly impressed with their speed, customer service, and attentiveness to the intricacies of aged baseboard radiators. I've never worked with any other home service companies who were willing to quote a new and innovative solution for a typically expensive repair. Keep up the great work!
TK Babington
TK Babington
Best plumbing company around :)
Brandon C. Adkins
Brandon C. Adkins
Carroll Plumbing & Heating has THE best customer service and response time of anyone I have ever used. I would highly recommend them!!!
I called this company due to an emergency that I had. My pipes burst and I had no heat or hot water and it was 14 degrees outside. Bruce was extremely helpful, kind and quick to solve the problem. They came out quickly, gave a reasonable estimate and stayed until they were assured the problem was fixed. Dave was a great help, along with the other gentleman who helped him. I will definitely use this company in the future and will recommend them to anyone with heating and plumbing needs! They are knowledgeable, have excellent customer service, and helped me out tremendously when I needed them. A+ job!
I called this company due to an emergency that I had. My pipes burst and I had no heat or hot water and it was 14 degrees outside. Bruce was extremely helpful, kind and quick to solve the problem. They came out quickly, gave a reasonable estimate and stayed until they were assured the problem was fixed. Dave was a great help, along with the other gentleman who helped him. I will definitely use this company in the future and will recommend them to anyone with heating and plumbing needs! They are knowledgeable, have excellent customer service, and helped me out tremendously when I needed them. A+ job!
Kimberly Earles
Kimberly Earles
The best customer service, honest, and fair pricing. I highly recommend them�
My Wife and I have been using Carroll Plumbing-Heating-Cooling for a variety of home plumbing (water and propane) "jobs" for approximately 4 years. Before describing our most recent experience, we wanted to share a summary of all the projects they have completed.

Our first experience with Carroll Plumbing-Heating-Cooling was during the total remodel of our kitchen and laundry room. This was an involved project since we completely changed the footprint of the spaces and therefore had to relocate all the plumbing. We were continually impressed with their professionalism, attention to detail and most of all - the daily communication on the progress/concerns and timeline updates regarding the plumbing related parts of the project.

Later, we decided to upgrade our conventional electric water heater to a Rinnai on-demand, propane-fueled water heater (including the installation of the required propane gas lines/connections, required valves). We consulted multiple contractors for bids and were pleased to see that Carroll Plumbing-Heating-Cooling were experienced installers/service providers of Rinnai on-demand water heaters and had competitive pricing for a "turn-key" project including the required Richmond City permits. We decided to go with Carroll based on our previous experience and were delighted again with the quality of their work, commitment to constant communication and competitive cost of the project.

Approximately 2 years ago, we again contracted Carroll to perform the plumbing related work; upgrades, etc. regarding the complete renovation of our main, full-bathroom. Their attention to detail in execution and communication with not only us but the other trades (tile, electrical, finish-work etc.) was impressive and refreshing.

Our most recent experience occurred during the week prior to Thanksgiving. On 11/19/2017, my Wife contacted Kim at Carroll Plumbing-Heating-Cooling regarding a problem we were experiencing (pipe-knocking/banging noises) after recently installing a new high efficiency washing machine. Kim immediately dispatched a plumber/Rinnai specialist and the identified the problem that day as a condition called "Waterhammering". The part was ordered and installed the next day at a surprisingly low cost.

Carroll has always satisfied our plumbing needs - we don't hesitate to call them when an issue or project arises.

Give them a call and experience their commitment to customer satisfaction yourself.
Carroll is the best HVAC & Plumbing company in town! Two years ago, I had 5 different plumbers take a look at a new water heater where the pilot was not remaining lit. All 5 incompetent plumbers (several whom has fancy commercials that air today) could not figure out the problem. The last plumber actually referred me to Carroll and I so glad he didn't allow pride to keep him from sending me to someone who knew what they were doing. A week before X-mas, Carroll came out, figured out the entire WH needed to be replaced (through warranty), and though they didn't install the old WH they handled the entire warranty process that included removing the old WH and installing the new one. The entire process was completed in 2 days. About 3 days after they installed it, there was slight condensation buildup on one of the pipes that concerned me and after calling, Carroll immediately came out and stopped it. Today, after turning the heat on for the 1st time since last winter, I noticed cooler air blowing. I called Carroll this morning and within a few hours the dispatcher had Jacob come by. Within a few minutes Jacob quickly diagnosed the problem (which was a closed valve that was mistakenly left off when they came out last time). Jacob was a peach and the dispatcher was very kind.
Tara Thomas
Tara Thomas
Carroll Plumbing was fantastic! They were able to get me an appointment the very next day after I first called and the technician (Kenny) that they sent out was efficient, friendly and explained everything thoroughly. We will definitely use Carroll for any future plumbing needs! I HIGHLY recommend them!
Christina Garnett
Christina Garnett
Carroll Plumbing came to our house within 24 hours of our initial call. Our technician, Dustin, was incredible. He was on time, polite, courteous and friendly. He fixed our shower, installed a new sink in our basement and replaced the main shutoff valve for our water. He was fantastic and we will ask for Dustin by name in the future. We have used Carroll Plumbing for over 15 years and were saddened when our former plumber retired. Fortunately, Dustin is absolutely top notch.
Blair Nelsen
Blair Nelsen
Carroll is always on pointe. They came today to fix a leaky and sticking shower. They had to take off 3 valve controllers to get to the problem and were very careful to keep all the trim and insides in great condition. I was worried about working on our expensive shower fixtures, but perfect job. They have done several fixes for me over the years - all great quality - so I figured it was time to give them the review they deserve.
George Smallfield
George Smallfield
Great team of guys...patient, pleasant and professional. Many Thanks!
Just the best in terms of product, service and follow-through!
I manage a business located down the street from Carroll Plumbing. We were having our internet upgraded and the contractor doing the work hit our water line. We were without water to our building at 3PM in the afternoon and were facing the possibility of having to close our business. I called Carroll Plumbing and they were over assessing the issue within 10-15 minutes. By 4:30PM our line was fixed and we were back up and running. I cannot thank Carroll Plumbing enough for turning what could have been a disaster into a tiny bump in our day.
Jackie Blosser
Jackie Blosser
Very thorough and personable, I've used their service for years on my HVAC units and recently had them replace my system, install new thermostats, and expand the ductwork. They are timely, clean up after themselves, always answer all of my questions and are never in a hurry. I will continue to use their services in the future.
Ryan Norwood
Ryan Norwood
Had a problem with a dripping faucet. Aragon from Carroll came out on a Sunday, quickly diagnosed the problem, fixed it, tested it and explained to me clearly what had happened. He was very friendly, on time, worked quickly, and used his boot covers while in the house. It was a great experience.
Neal Lappe
Neal Lappe
Great company to deal with if you need plumbing work. This most recent need for Carroll was to replace my 16 year old hot water heater. They called me to let me know they were running behind and then called me to tell me the plumber was on his way. After the hot water heater was installed, the plumber reviewed it operation with me. I will use Carroll again.
Elizabeth Long
Elizabeth Long
We came home from work in early spring to find our furnace not working. Carroll came out the next day to look it over. They performed a quick fix until the part that was needed came in. They were back the very next day (on a weekend), working hard to get it working. Everyone from the folks in the office to the technician who did the work were professional and very helpful.I highly recommend Carroll Plumbing and will surely call them first when I need any heating or plumbing work.
Tricia Stohr-Hunt
Tricia Stohr-Hunt
We are in the process of renovations on our 1932 home. Bruce, Jeff, and Jim have provided great service and technical expertise on boiler and hot water heater replacement, HVAC, and general plumbing. They and their assistants are on-time, courteous, friendly, patient, responsive, skilled professionals. We couldn't be more pleased!
My first encounter with Carroll Plumbing and Heating was in 2006, while working for a competitor of Carroll's. As I recall, I was intimidated and thought, "I would never be able to work for them (Carroll Plumbing and Heating, CH&H)". C.P.& H. does not just rip out and replace. This company specializes in repairs. Finding innovative ways of making difficult situations work in their favor, for the sake of the customer.
When I went to apply for a job, I was taken in and assigned to work with Tommy Hall. Tommy taught me so much about plumbing, I now can use his snarky remark of "I forgot more about plumbing than you know" when I talk to other plumbers.
Today, I own and operate a sewer and drain company in Massachusetts. Just yesterday, I was given such a complement and was reminded, I learned from the best.