Fixing a leaking compression joint
⚠️ Turn off and drain the relevant pipe section before starting.
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Turn off the water supply and drain the section of pipe.
Dry the joint completely and tighten the nut a quarter-turn. Turn the water back on slowly and check — often this resolves a minor weep.
If it still leaks, turn off again. Undo the nut completely and slide it back along the pipe to expose the olive (the small brass ring).
Wrap 4–5 turns of PTFE tape around the olive before re-tightening. This often seals a weeping olive without needing to replace it.
If the olive is badly deformed or cracked, cut the pipe back, fit a new olive, and reconnect.
Do not over-tighten compression fittings — firm hand-tight plus a quarter-turn with a spanner is sufficient.
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