Pressure Reducing Valve Placement

[Ralph]

Sorry if this is a dumb question but do you put the PRV inside our outside the house?  We have 15 bar coming from the main so need a valve before the water company connect us. 

 

Also what are the chances of failure with a PRV? 15 Bar / 217 PSI seems like a lot of pressure. 

 

Thanks in advance

 

 

[Conor]

The water company need to have a PRV fitted between the main and the boundary box as it will only be rated to 11 or 12.5bar. you need to take it up with them. Highly unusual that you have mains pressures over 10bar these days, unless you are on a pumped main that serves high properties and you are at the bottom.

[Ralph]

4 minutes ago, Conor said:

The water company need to have a PRV fitted between the main and the boundary box as it will only be rated to 11 or 12.5bar. you need to take it up with them. Highly unusual that you have mains pressures over 10bar these days, unless you are on a pumped main that serves high properties and you are at the bottom.

Scottish water have said "our Network Engineers have recommended you fit a Pressure Reducing Valve (PRV) between the stopcock and your property." From what you've written I'm wondering if they fit one on the their side of the boundary box but we also need to fit one on our side. 
 

We're connecting to the network pipe that comes from the reservoir and supplies the town about 5km from us. It runs through the front of our plot. 

[Conor]

Strange, any water company I've worked with before would fit a PRV before the boundary box in order to protect it (their assest).

[DundeeDancer]

Interesting thread. I was starting to think our mains pressure within our flats is high at just over 4 bar.

 

A plumber is telling us via the factor that to reduce "water hammer" from some of the flats we should all (18 flats) fit a PRV, just after our own individual flat stopcocks.

I'm not to fond of that idea because that would be 18 new points of potential failure in the plumbing system within our building envople.

In my mind a better solution would be to fit in the garden somewhere just one master PRV for the development which would take the pressure down from 5 bar or so down to ideally 2.5 bar.

 

Thinking 2.5 bar is optimum pressure for domestic use? That will still give more than enough pressure for showers heated up from combi boilers etc.

 

So yeah interested to hear where you finally choose to place your PRV Ralph. DD ?

[Nickfromwales]

2 hours ago, DundeeDancer said:

one master PRV for the development which would take the pressure down from 5 bar or so down to ideally 2.5 bar.

You may find that strangles the flow rate. Not something you'd want with 18 flats off it  

[Ralph]

2 hours ago, DundeeDancer said:

So yeah interested to hear where you finally choose to place your PRV Ralph. DD ?

It's not in yet but I think it's going to be a unit with a PRV and stopcock in a box down the bottom of the garden. 

[DundeeDancer]

18 hours ago, Nickfromwales said:

You may find that strangles the flow rate. Not something you'd want with 18 flats off it  

So would you say it is reasonable to have 4.5 bar coming off the main into one’s property and having that pressure in the domestic pipes is a little high but still OK? My flat seems to be dealing with that pressure OK so I don’t see the need to add to the system a Pressure Reducing Valve. My neighbours are suffering a bit from water hammer but maybe their systems have less room to flex than mine / less expansion built in that my plumbing & connected appliances have.