I've got decent mains water pressure and flow at the garden tap - around 3 bar and 30 lpm. But the pressure on the first floor is about
0.8 bar, and the flow is under 10 lpm.There's less than 3M height difference between the garden tap and the first floor tap level, so I'd expect to see at least 2.5 bar on the first floor.
The only thing I've got in my system that I think could be affecting the static pressure is a pressure reducing valve (prv), which is part of a megaflo system. Both the cold and hot water for the first floor taps appears to be after this prv. Here's a photo of the megaflo prv:
The prv is the big thing in the middle of the picture, with a black cartridge screwed into the top.
The system was installed around 1999, so maybe the prv has become worn or clogged up or something.
I'm wondering if I should take the prv cartridge off and clean/service/replace it? Or am I barking up the wrong tree?