Furnace Making Popping Noises – What To Do?

Disclosure: We may get commissions for purchases made through links in this post.

Furnaces ensure our homes are properly heated during cold weather. Over time, their parts can wear out, creating different types of noise. If your furnace makes a popping sound and you're not sure why. Here's what experts think might be the cause. 

A popping sound from your furnace is most likely from the air ducts, as temperature changes can repeatedly cause them to expand and contract. The noise can also come from dirty burners. Whatever is the cause of the noise, you should call a technician for repairs. 

Popping sounds can be caused by different issues apart from the two mentioned above. To learn more about unusual noises furnaces make, keep reading. 

A home high efficiency furnace with a residential gas water heater & humidifier - Furnace Making Popping Noises - What To Do

Reasons Your Furnace Makes a Popping Sound

Framed home installation of air conditioner and heating ductwork in ceiling a new home HVAC

Your furnace might make a sound for many reasons, but here are the most likely causes. 

Ducts With No Insulation

Air ducts are a passage for air from the outside to the inside of a building. They are used in furnaces to distribute heat and cool air. Air ducts can also be used for other purposes like heating and ventilation.

Air ducts pass through walls, floors, ceilings, or any other suitable passage in the building. They come in different shapes and sizes. The size of an air duct depends on the amount of heat or cool air it needs to pass through it.

Insulation is a critical component of air ducts that prevents heat transfer and helps to maintain a comfortable temperature. It is essential to insulate your air ducts because they are a significant source of heat loss. The older your home, the more likely it is that you have air ducts that are not insulated. 

This means your ducts are susceptible to temperature change. At extreme hot and cold times in a year, the temperature on each end can be different, so the air movement from one point to the other can result in a popping sound. 

Expansion of Air Ducts

When temperatures dip below freezing, air ducts in your furnace tend to contract. The air ducts can also expand and contract depending on the air temperature being transferred through them.

When they expand, they can cause a harmless popping sound. This expansion and contraction are not always noticeable. Sometimes, this expansion may lead to very noticeable and bothersome noises.

Cheap and Thin Sheet Furnace Metal Ducts

When constructing metal ducts, it is vital to use quality materials. Thin sheet metal creates noise in air ducts, which can cause issues with airflow and produce popping sounds.

The best material for metal ducts is rubber, stainless steel, silicon, and PVC. These materials are less noisy and have better airflow than thin sheet metals like aluminum.

PVC is a type of plastic used in many applications, including air ducts. It is resistant to temperature change and can last a long time. PVC's advantages make it ideal for constructing air ducts. They are durable and resistant to temperature change, have high tensile strength and low weight, and do not rust easily.

How Do I Stop My Air Ducts From Popping

ventilation system installation and repair service. hvac technician at work. banner

Since you have understood the common reasons why your furnace air ducts can create popping sounds, here are ways to stop these sounds. 

Insulate Your Furnace Ducts

Lack of insulation in your furnace air ducts can make them vulnerable to temperature changes. Air ducts are also a source of moisture and condensation. This can lead to mold and bacteria, which is unhealthy for the owner and the people who live nearby.

It is important to insulate your air ducts to prevent this from happening. There are many different insulation materials that you can use, such as fiberglass or foam. However, fiberglass is known to be slightly ineffective with sound insulation, so the foam is usually a better option.

Air Seal Your Furnace Ducts 

Air leaks in ducts can cause several problems. They can cause sound in the duct, which is unpleasant for people living in the home. Additionally, air leaks can cause damage to the HVAC system and make it less efficient.

The most common causes of air leaks are poorly installed ducts or improper insulation. You should seal any leaks in the air duct before insulating it.

Replace Your Furnace Ducts

Air ducts are one of the most important parts of the HVAC system. They help to circulate air and prevent indoor air quality problems.

Air ducts, however, are susceptible to damage and require replacement. If you’re dealing with popping noise from the furnace, replacing your furnace air ducts is recommended. Replacing an air duct is less expensive than insulating it, so it is often better to buy new ducts altogether.

New modern air ducts are insulated and sealed to make them more durable than old ones. This helps reduce the cost of replacing them while also ensuring that they provide better air exchange.

Can a Furnace Explode? 

A furnace is a vital part of your home. It provides warmth, heats water, and helps to keep the air clean. But what happens if it explodes?

A furnace can explode, but modern furnaces are built to prevent this from happening. They have high-tech sensors to detect when the furnace is overheating and shut it down. However, if these sensors stop working, you should consider replacing your furnace with a new one.

The most common causes of furnace explosions are gas leaks and faulty wiring. Some other causes include power outage or equipment failure, improper maintenance, opening or closing doors when the furnace is still hot, which creates an airlock, or using a lighter or match near the unit.

Furnace manufacturers are required to add safety features that will prevent the furnace from exploding due to a fault or error in the design process. However, there are still things that you can do to maintain your furnace and stay safe.

Some of these preventive measures include:

  • Checking your gas supply every month
  • Inspecting for problems with the venting system
  • Checking for issues with the gas line
  • Observing proper ventilation in your home

Can My Furnace Catch on Fire?

A home high energy efficient furnace in a basement

Furnaces can catch on fire if you don't take care of them properly. To prevent the furnace from catching fire, it is important to check the furnace for dirt accumulation and overheating. If the wiring is faulty or if there are bad parts, this can cause a fire.

Some of the signs that you should watch out for to avoid fires;

  1. Smoke from the furnace
  2. A foul smell coming from the furnace
  3. The appearance of flames coming out of your vents or chimney
  4. The temperature in your house goes up significantly

Abnormal Noises From Furnace [And Their Meanings]

It is normal for mechanical devices like furnaces to make noise sometimes, but some noises can be unsettling. They call for an inspection and possible repair. Apart from a popping sound from your furnace, here are other sounds you should watch out for. 

High-pitched Whistling Sound

A blower motor can be found in furnaces and air conditioners. It is responsible for moving air from the furnace to the room. A damaged blower motor can cause a whistling sound and may strain to draw in air when it's damaged.

A homeowner needs to know the symptoms of a damaged blower motor so that they can fix it before further damage occurs. If you notice this, you should turn off your furnace and contact an HVAC professional to have it repaired.

Rattling Sound

Loose parts in your furnace can cause a rattling sound, which is not a good sign. The sound is typically caused by parts like panels and loose doors in the furnace.

When the loose parts hit each other, they create a sound that can be disruptive and unsettling. If you hear the rattling sound, it is important to turn off the furnace, tighten loose parts, or call an HVAC technician.

There are two main reasons for the rattling noise in your furnace:

1) Loose parts that should be tightened

2) A broken part that should be replaced

Buzzing Sound

If you hear a buzzing sound in your furnace, it might be because of an issue with the motor. The motor fan is faulty and needs to be replaced.

A faulty motor fan usually causes buzzing sounds in a furnace. This can happen when the fan suddenly stops working or is not operating at its maximum capacity. If you hear a buzzing sound coming from your furnace, turn it off and call an HVAC company to check out your appliance.

Technician looking over a gas furnace with a flashlight before cleaning it.

In Summary

A furnace is an important appliance in any home. It heats the air and helps keep your home warm and comfortable in the wintertime. If you notice unusual sounds coming from your furnace, it is time to call an HVAC technician. 

If you enjoyed reading this article, you should check out these similar posts: 

How Much Space to Leave Around a Furnace? 

How to Reset a Gas Furnace

Leave a Reply