hammering and pressure loss - post boiler install

[darnok]

Hello, just had a Worcester 30Si combi boiler installed and now one of the hot water taps developed a new problem. On the first twist - I get a bit of pressure, second twist - less pressure, third twist - loud disconcerting hammering, fourth turn - good pressure, no hammering. The problem occurs on the bathroom hot water tap (not a mixer), located 1 floor above the boiler. The installer blames the tap, as the kitchen mixer tap (downstairs, next to the boiler) is problem free, even when turning on just the hot water.


The 30Si replaced an old Potterton with a hot water tank, radiator flushing was provided. The installation is due to be inspected for certification (same company), and I wonder if it makes sense to stall the process till they resolve the issue?

 

[IDCHAPPY]

You can change tap cores for about £20 worth of parts(tap reviver kit) would be a good first port of call

 

[lame plumber]

Id pay the installer to repair your tap or you may be getting something for Xmas you didnt want.

 

[Chalked]

Not installers fault. It's a faulty tap.
Pay them and ask if they would replace.

 

[steadyon]

Or a new washer and make sure its not loose on the jumper.

 

[Nostrum]

Or just turn it one twist, hey presto, best of both worlds!

 

[0304Driver]

As others have said its a faulty tap/ tap washer. This has shown as a fault now because you have changed from a hw cylinder to a combi.

 

[darnok]

Many thanks to all, will be fixing the tap ASAP.