Boiler Airlock Explained | Causes, Symptoms & How to Fix an Airlocked Boiler (UK)

Описание: A boiler airlock is a common heating problem in UK homes and can stop your boiler from working properly. If you’re dealing with cold radiators, no hot water, or a boiler that keeps cutting out, trapped air in the system could be the cause.

In this video, we explain what a boiler airlock is, how it happens, the warning signs to look out for, and what you can do to fix an airlocked boiler safely.

🔥 What is a boiler airlock?

A boiler airlock happens when air becomes trapped inside the heating system, stopping water from circulating correctly. Because boilers rely on steady water flow, trapped air can cause the boiler to shut down as a safety measure.

Airlocks often occur after:
• A new boiler installation
• Draining and refilling the heating system
• Radiator replacement or repairs
• Boiler servicing or maintenance
• Low boiler pressure issues

🚿 Symptoms of a boiler airlock

Common signs your boiler may be airlocked include:
• Radiators staying cold when heating is on
• Gurgling or bubbling noises
• Boiler firing up then switching off
• No hot water from taps
• Uneven heating across radiators
• Boiler pressure dropping repeatedly

Ignoring these symptoms can lead to reduced efficiency and further boiler problems.

⚠️ What causes air to get trapped in a boiler system?

Air can enter your heating system due to:
• Incomplete radiator bleeding
• Small system leaks
• Poor circulation
• Incorrect refilling of the system
• Pump or valve faults
• Sludge restricting water flow

Older or poorly maintained heating systems are more likely to suffer repeated airlocks.

🛠️ How to fix a boiler airlock

Some airlock issues can be resolved with simple checks, while others require professional help. In this video, we cover:
• How bleeding radiators can release trapped air
• Why correct boiler pressure matters
• How circulation issues cause airlocks
• When a power flush may be required
• Why pump or valve issues can trigger repeat problems

We also explain why certain fixes should only be carried out by a Gas Safe registered engineer.

👨‍🔧 When to call an engineer

If bleeding radiators doesn’t work, or your boiler:
• Keeps losing pressure
• Won’t stay on
• Shows fault codes
• Makes unusual noises
• Has no heating or hot water

It’s time to get professional advice. Ongoing airlocks usually point to a deeper system issue.

💷 Can a boiler airlock damage your boiler?

Yes. Left untreated, trapped air can cause overheating, pump failure, reduced efficiency, and increased wear on boiler components — potentially leading to costly repairs or even boiler replacement.

📅 How to prevent boiler airlocks

Preventative steps include:
• Annual boiler servicing
• Correct system refilling after maintenance
• Maintaining correct boiler pressure
• Power flushing older systems
• Fixing leaks quickly

Regular maintenance helps prevent airlocks and extends your boiler’s lifespan.

🌍 Need help with your boiler?

If you’re experiencing boiler problems or need a new boiler replacement, compare boiler quotes online in minutes at:
👉 https://www.boilers2go.co.uk

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