Boiler Kettling

Boiler Kettling: Causes, Signs, and Fixes

Have you ever heard banging or rumbling sounds coming from your boiler? That could be kettling. Although it might seem minor at first, ignoring it could lead to bigger problems. In this post, we’ll explain what boiler kettling is, why it happens, and what you should do about it.

What Is Boiler Kettling?

Kettling happens when water inside the boiler heats up too much and forms steam bubbles. These bubbles expand and collapse, creating banging or rumbling noises. It sounds a bit like a kettle boiling — which is how the problem got its name.

What Causes Boiler Kettling?

Several issues can cause kettling. Let’s go through the most common reasons:

1. Limescale Buildup

In hard water areas, minerals like calcium and magnesium can collect inside the heat exchanger. This buildup restricts water flow, causing overheating and steam bubbles to form.

2. Sludge and Debris

Rust, dirt, and debris can also block water flow. As water moves slower through the system, it heats unevenly, which triggers kettling noises.

3. Low Water Flow

Sometimes, problems with the pump or valves can reduce water circulation. When water doesn’t flow properly, certain areas get too hot and create steam pockets.

4. Faulty Thermostat or Controls

If the boiler’s thermostat isn’t working right, it might allow the water to overheat, increasing the chance of kettling.

Is Boiler Kettling Dangerous?

While kettling doesn’t usually pose an immediate danger, it can damage your boiler over time. The longer the issue continues, the more strain is placed on internal parts. Eventually, this can lead to expensive repairs or even full boiler replacement.

How to Fix Boiler Kettling

Although some simple fixes exist, many kettling problems require a professional. Here are a few options:

• Power Flushing: This process clears out sludge and limescale from the system.
• Descaling: Special chemicals remove limescale from the heat exchanger.
• Component Checks: A professional can inspect the thermostat, pump, and valves for faults.

Preventing Boiler Kettling

To reduce the risk of kettling, regular servicing is key. An annual boiler service can catch early signs of buildup or circulation problems. In areas with hard water, fitting a water softener or limescale reducer can also help prevent mineral deposits from forming.

Get Professional Help from Plumble

If your boiler is noisy, don’t wait for it to get worse. At Plumble, our qualified engineers can diagnose and fix the problem quickly. Serving homes across Kent, we’re here to keep your heating system running smoothly. Contact us today for expert boiler repair and servicing.