If your boiler is making unusual noises, it's usually a sign that something isn't working properly.
While some noises are harmless, others can indicate a more serious issue that needs attention, especially when gas and heating systems are involved.
In this guide, we'll explain the most common reasons boilers make noise, what you can safely check yourself, and when it's time to call a professional gas engineer.
Common Boiler Noises (And What They Mean)
Different noises can point to different problems.
Banging or Knocking Sounds
This is often caused by a build-up inside the system, restricting water flow.
As water heats up, it can create pressure that leads to banging noises.
Common cause:
- Sludge or limescale inside the system
Whistling or "Kettling" Noise
A high-pitched whistling sound, often called kettling, usually means water is overheating in certain areas due to restricted flow.
This is commonly linked to:
- Limescale build-up
- Poor circulation
Gurgling Sounds
Gurgling noises often indicate:
- Air trapped in the system
- Water not circulating properly
This is a common issue in radiators and pipework.
Vibrating or Humming
If your boiler is vibrating or humming, it could be caused by:
- Pump issues
- Loose components
- Flow-related problems
This usually needs checking properly.
Safe Checks You Can Try
There are a few simple and safe checks you can carry out before calling an engineer.
Bleed Your Radiators
If air is trapped in the system:
- Bleeding radiators can help restore proper flow
- This may reduce gurgling noises
Check Boiler Pressure
Low or incorrect pressure can affect performance.
Most boilers should be around 1-1.5 bar.
Check Thermostat & Settings
Make sure:
- Heating is set correctly
- The system is running as expected
Do NOT attempt to open or repair the boiler yourself. Internal components should only be handled by a qualified gas engineer.
When to Call a Gas Engineer
If the noise continues or gets worse, it's best to get it checked.
You should call a gas engineer if:
- The boiler is making loud or persistent noises
- Heating performance is affected
- The system keeps turning off
- You hear banging, whistling, or vibrating regularly
- You suspect a fault inside the boiler
These issues usually require proper diagnosis and repair.
Professional Boiler & Gas Services in Kent
At Adam Gas Plumbing and Heating Kent, we deal with all types of boiler and heating system issues.
We provide:
- Boiler repairs and fault diagnosis
- Boiler servicing and maintenance
- System cleaning and improvements
- Safe and compliant gas work
We focus on identifying the cause and fixing it properly.
Local Gas Engineer Near You
We provide boiler and gas engineer services across:
If you're searching for a "gas engineer near me", we're ready to help.
Need Help With a Noisy Boiler?
If your boiler is making noise and the issue isn't resolved, it's best to get it checked before it turns into a bigger problem.
Call +44 7716 026508 to book a visit or email info@adamoilngas.com.
We provide reliable boiler and gas services across Kent.