Replaced ball cock valve now pipes are noisy

[ss90]

My loft tank ball valve started leaking, so I replaced it with a like for like part from screwfix but it was whistling like crazy. I assumed it may have been faulty or just substandard so brought a more expensive part. The whilstling from the valve has gone, but now the pipes from the main stop cock make a horrendous racket!
It’s definitely the same gauge and a high pressure part. The isolator valve and all other isolators are turned back on fully. As the tank nears full it quietens off, I’m presuming as the valve starts restricting the flow. Any ideas, I’ve changed nothing else.

 

[Deleted member 267285]

Is it a continuous noise, or like tapping?

 

[ss90]

Continuous and it’s through the pipes particularly downstairs. Put the old valve back on and no problem noise goes

 

[flameport]

part from screwfix

Which exact part from Screwfix?

 

[Deleted member 267285]

Could be a faulty valve. As per flameport, what part? Was it like for like?

 

[ss90]

I think the screwfix one was definitely faulty, but I replace with a slightly more expensive one and although the whistling at the valve has gone, the noise through the cold water pipes remains as if it’s being restricted.
The screwfix part was a high pressure 2 part flomasta ball valve.

 

[Deleted member 267285]

Does the old one come out the same flow rate/force as the new one?

 

[polesapart]

Try a Fluidmaster (side entry) ballvalve. If it comes with a flow restrictor, fit it.