You can turn the cold water to the boiler of but this is not really advisable as the valve tends to leak when turned back on If i was you Iwould just turn the main stop tap off where it enters the house
steve
September 2009
thanks done it
pd
September 2009
Either - the rubber washer on the bottom of the tap insert has split or, if the tap is the quarter turn type, the ceramic insert has failed. Shutting the boiler off and turning the water off will allow you to make the repair.
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