: I recently drained the radiator system when I removed
: one of the radiators in a downstairs room.
: I then released the cold water tap to top the water upto the 1.5 bar mark and turned the system back on.
: However water started shooting out from the air vent cap above the pump in my Valiant boiler.
: I thought the problem had been resolved when I tightened the cap but I still have a small leak coming
: from this cap.
: Please can you advise what I have done wrong and if I can resolve.

Reply:
If it's a float type automatic vent with a Schrader valve on top, you may need to replace it.
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