if the pipes are boxed in then yes you might hear some sounds especially if there is some air in the system.if you have a leak the pressure gauge will drop and stop the system working
A1
January 2012
No that does not sound normal.
If your pressure gauge is dropping then you have a leak from a pipe. What point is the needle on the gauge sitting at?
Is the boiler working ok other than the noise?
Neil.
January 2012
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