Shower pressure dropping (unvented cylinder)

[Dan1983]

Evening all,

We have been in our build just over 2 years now and had a quick question about the shower flow!

When you first put the shower on flow/ pressure is really good, then after about 1 minute it seems to reduce a fair bit.

our mains pressure seems to be at 2.5 bar and then drops to about 2 bar with a fully open hot tap

Cold seems fine and I’ve often felt upstairs it’s too high as when you flush a toilet some of the initial flush water slightly splashes up 

It looks like there is a PRV on the mains inlet in kitchen but not sure what I can adjust on the cylinder side of things to maybe give better pressure upstairs?

 

[Dan1983]

[Mattg4321]

Do you have a problem with flow rather than pressure maybe?

[Dan1983]

Only thinking not Matt as initial flow seems good.

I did take the shower head off last night and the filter/ gauze was about 1/4 clogged with plumbers mate type residue.

Its had a water softener from new but maybe the head is slightly blocked?