Airlock in Hot or Cold Pipework
A tap that spits, runs briefly then stops, or gives nothing at all after work on the system..
A tap that spits, runs briefly then stops, or gives nothing at all after work on the system.
What is actually going on
A tap that spits, runs briefly then stops, or gives nothing at all after work on the system.
The realistic causes, in order
Air drawn in during a drain-down that hasn't been cleared on refill A pipe run with an unavoidable high point that traps air A cold tank that ran empty, filling the pipework with air
What we test on site
Whether the affected outlet is gravity-fed or mains-fed, which changes the clearing method entirely Pipe routing for high points that will trap air again Cistern level and fill rate
Get an airlock in the pipework diagnosed properly
Clearing the air is quick; correcting the pipe route or fill arrangement is what stops it recurring.
Questions we get asked
Where does an airlock in the pipework usually start in the pipework?
Air drawn in during a drain-down that hasn't been cleared on refill
What normally puts an airlock in the pipework right?
Clearing the air is quick; correcting the pipe route or fill arrangement is what stops it recurring.
Is it safe to keep using the system with an airlock in the pipework?
Cross-connecting hot and cold supplies as a permanent arrangement is not acceptable under the water regulations — it's a temporary technique only.