Poor flow rates

[jpadie]

Hi all 

 

I've been having poor flow rates in the kitchen and bathroom for as long as I can remember.  about 3 years ago I changed out the PRV and twisted the adjuster until my other half said the sink was filling quickly enough.  Job done I thought.

 

Lots of dripping from the pressure relief valve going to the hot water cylinder (whether the water was warm or not) and sometimes a lot of flow from the PT valve on the cylinder got me thinking about water pressure generally.  the manometer on the PRV and a test manometer I fitted to a tap bib show inside pressure at 7bars.  this stays the same whatever I do to the PRV although the flow rate seems to change a bit when the PRV is adjusted.   I've cleaned out the PRV completely (but it is not a replaceable cartridge type, just having a metal grille.  I cleaned it by giving it a citric acid bath for a few hours, then some mechanical flushing).

 

pipework is wide bore MDPE coming into the house (42mm I think) going to 22mm copper into a low loss manifold from which there is 15mm PEX lines going to the kitchen and the master bathroom (separate lines).  

I _think_) the mixer taps may be very narrow bore (I will check) but I was wondering whether there was any advice from the community about

 

1. what other things to look for in investigating low flow rates; and
2. what causes a PRV not to adjust the pressure?

FYI there are three outdoor water outlets that are on the supply side of the PRV and they are all good flow (e.g. I use 25mm  mdpe to a 100m3 pool and it fills up within the inside of a summer's day (16-17 hours)).

 

thanks in advance

Justin  

 

[jpadie]

Changed the prv to a new reliance 22mm version and that has certainly helped stop with flow and stopping the persistent dripping from the hot water circuit.

 

Flow rate from the kitchen taps is low at 4.5l/minute.  Cartridges are clean. 

 

I think the only solution to this is to change the tap for a higher flow rate alternative but I am open to suggestions before investing in new hardware