BoilerTroubleshooting2026-02-26
Airlock in Your Heating System
An airlock blocks circulation and leaves radiators cold — bleeding usually clears it.
Trapped air can form an airlock that stops hot water circulating to your radiators.
What causes it
Air enters during filling or from corrosion and collects at high points, blocking flow to radiators.
How to clear it
Bleeding radiators in the right order usually clears an airlock; stubborn cases may need the pump and system purging.
Key takeaways
- Airlocks block circulation
- Bleed radiators to clear air
- Check pressure afterward
- Stubborn locks need purging
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