Updated May 18th, 2025
Typically, vented heating systems operate silently; however, steam or hydronic systems may occasionally produce unexpected sounds, such as loud banging. Coping with consistent, disruptive noises can be challenging, especially when relying on your heating system to effectively warm your home.
How to Deal with Heating Pipes that Are Making Loud Banging Noises
Heating systems work by forcing heated air or hot steam through an intricate network of pipes. Heated air is dispersed through vents, while hot steam is sent through pressurized pipes and into radiators that “radiate” heat as the hot water passes through them. Usually, heating systems produce a low level of sound, but heating pipes making loud banging noises can indicate a problem that mostly results from one of the three issues mentioned here.
Also read: 7 Tips to Make Your Heating System Well-Equipped for Winter Comfort
1. Boiler Kettling
Kettling issue is most common in hard water areas, where the boiler’s heat exchanger accumulates limescale that constrict the flow of water. The heat exchanger becomes too hot and ultimately expands and causes heating pipes to making loud banging noises.
How to fix the kettling problem in heating pipes
This problem can be tackled by professionals who will offer the best limescale removal solution, according to the severity of the issue.
2. Trapped Air
Another reason for the rattling, clanging, and banging noises in your heating system is the air bubbles getting trapped in the water in your heating system. Due to the expansion and collapsing of air bubbles as they travel through the heating pipes, loud clicking noise can be heard.
Also read: Furnace Maintenance: Things You Should Know
How to Fix Banging Due to Trapped Air in Heating Pipes
An effective way to stop noise is to remove the air bubbles from the pipes. This process is known as “bleeding” the pipes and it involves the following steps:
- Turn it off the system before bleeding
- Look for the small valve present under the end cap of the radiator and rotate it counterclockwise to remove the air pressure.
- As the air exits the pipes and the water starts to trickle out, you should close the valve
- Turn on the system after completing the above steps with each radiator
Hiring an HVAC technician to bleed trapped air from your heating pipes offers several compelling benefits. HVAC professionals possess the expertise and specialized tools necessary to efficiently diagnose and address the issue, ensuring thorough and effective results. Additionally, their experience enables them to identify any underlying issues that may be contributing to the air buildup, preventing future occurrences and potential damage to your heating system. Hire a residential HVAC contractor to help you resolve this issue effortlessly.
Also read: Furnace Duct Cleaning: Know About Their Pros and Cons
3. Expanded Pipes
When heating pipes become very hot, they expand and cause pipes to shift slightly. However, when the pipes are situated on a hard surface, banging noises will be produced with the slightest movement on their expansion.
How to Fix Banging Heating Systems Due to Pipe Expansion
Placing small pieces of foam near pipes that travel through wooden supports will prevent banging or other bumping sounds. If this does not fix the issue, seek professional help by hiring residential heating services. You don’t have to live with heating pipes that bump and bang all night. Improve your heating system’s functions by following the tips mentioned above. You can also have a residential heating and cooling contractor to check your system and eliminate noisy pipes.
Understanding Water Hammer
Water hammer happens when valves close suddenly, sending pressure surges through your pipes that create loud banging noises. These pressure spikes can stress joints and fittings if left unaddressed.
Installing Shock Absorption Devices
- Water hammer arrestors: Compact devices filled with air or gas that cushion pressure spikes. Install them near fast-closing valves (like on washing machines or dishwashers).
- Surge tanks or expansion reservoirs: Larger chambers that absorb more volume. Ideal for whole-house systems to protect long runs of piping.
Checking Pipe Layout & Support
- Proper slope: Ensure horizontal runs drop slightly back toward the boiler or main line to prevent trapped water from causing kettling sounds.
- Secure mounting: Use pipe straps or cushioned hangers at regular intervals to eliminate rattling. Wrap clamps with foam sleeves to further dampen vibration.
Balancing Pump Speed & Pressure
- Adjust pump speed: Running the circulator at a medium setting reduces flow velocity and minimizes shock waves.
- Maintain correct pressure: Keep system pressure within the manufacturer’s recommended range (usually 12–15 psi) to avoid excessive velocity.
- Bleed air regularly: Air trapped in radiators or pump housing collapses under flow changes—bleed vents until only water emerges.
Preventive Maintenance Tips
- Annual system flush: Remove scale and sediment that can contribute to noisy flow.
- Inspect valves & fittings: Replace any that show signs of corrosion, binding, or delayed closure.
- Check expansion tanks: Ensure bladder-type tanks are properly charged and not water-logged, so they can absorb pressure changes effectively.
Contact us today to schedule an HVAC maintenance with our experts and get a quick and effective resolution for all your residential HVAC problems.
Trust White Mechanical, Inc. For All Your Heating Maintenance Needs
Founded in 2002, White Mechanical, Inc. in Laguna Hills, CA, is one of the most trusted and licensed (HVAC) service providers, proudly serving Orange County and the surrounding communities. Our management team has more than 28 years of experience in various aspects of HVAC technology. All our HVAC technicians are professionally skilled and certified to deliver outstanding residential HVAC services as well as commercial HVAC services to our clients. We offer professional HVAC services including installation, maintenance, air conditioning repair, and more at very reasonable prices.
