hi, make sure the vent pipe from cylinder is not blocked with ice above tank in roof. sounds like air lock in hot water system . probably need plumber to force mains water in to hot system to clear. or do it yourself if competent to do so . cheers!
marti
January 2011
When u say no hot water do you mean the water runs cold or the water does not run from tap at all. If there is no water check the tank in th attic is not dry (which supplys cold water to the cylinder). If the tanks is full and seems to operating correctly, check that the cold feed to the cylinder has not been isolated (the gate valve has been turned off). If none of the above then u have a blockage or an air lock. Please message back for suggestions on how to fix.
Chris
January 2011
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