Plumbing advice · Leaks & Burst Pipes
Airlock in Your Pipes? How to Clear It
A spitting, coughing tap after plumbing work is usually trapped air.
How to tell it is an airlock
One tap spits, coughs and dies while the others run fine, usually just after work on the system or a drained tank refilling. If every hot tap is dead the problem is upstream at the boiler or cylinder, not air.
The hose trick
Connect a short hose between the mains cold tap and the affected hot tap, open both for thirty seconds, and mains pressure pushes the air plug back up the pipe. Two or three rounds usually clears it.
If it keeps coming back
Recurring airlocks mean pipework laid without proper falls, or a tank fill problem letting air draw in. That needs a survey rather than a weekly hose ritual, and it is a small job to put right.
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