Pressure Reducing Valve limiting mains water pressure why?

[ecswtrav]

Hello,


I was hoping someone could answer a query that has puzzled me for a while and nobody has been able to help all that much. I have a new mains water supply coming into the basement which has replaced the old lead version. This new connection is instantly greeted by a pressure reducing valve set at just over 2 bar on the meter. My boiler is an ideal iStor (unvented cylinder bolted on to a condensing boiler) - they don't have a good reputation - but this one has caused me very few problems over the past 3 years as its serviced annually. Up to now it works just fine.
Anyway, my showers and taps aren't exactly bursting with power/flow/pressure/ or whatever the technical phrase is. In fact, its no different to the old lead supply. However, I decided to adjust the PRV with a screwdriver and turn the pressure up to see what happened. Instantly the water comes flying out of the taps/showers with some force etc - just how I'd like it. I instantly brought it back down to 2 bar though.
I Wondering what the purpose of this device was, I read the Ideal istor manual and it says this must be installed as the boiler cannot operate on more than 2bar of mains pressure. In fact, the actual boiler comes with the valve when you buy it so it seems.


Why on earth would anyone want to restrict their mains pressure like this? Is there anything I can do to take advantage of having a new mains supply with extra pressure?


I assumed maybe the meter on the PRV was knackered and not giving the correct reading? It could be set at 1bar but showing just over 2? I did notice it reduced in pressure when a tap is switched on - I assumed it would be a constant 2 bar?


Anyway, any advice I'd be very grateful. Thanks

 

[ShaunCorbs]

get a g3 engineer to have a look but sounds like the boiler/cylinder is only rated for max a 2 bar

 

[ecswtrav]

I did ask the guys sent to service the boiler recently - not a clue. They didn't even know the thing was a PRV! Not sure that means much though. Any G3 guys on here who could advise?

 

[ShaunCorbs]

I did ask the guys sent to service the boiler recently - not a clue. They didn't even know the thing was a PRV! Not sure that means much though. Any G3 guys on here who could advise?

do you know when the valve was installed same time as boiler/cylinder?

 

[dancinplumba]

shaun has given you advise, what other advise do you want ?

 

[ecswtrav]

Shaun thanks for that. It was fitted, I assume, with the boiler which was around 2.5-3 years ago. I always felt the shower was really powerful when I first moved in and somewhat hurt the skin...just dont know whether im used to it now but it certainly isnt powerful. dancinplumba - just wondered why a boiler would be designed to not utilise full mains power and require a reducing valve - is this normal?

 

[ShaunCorbs]

Shaun thanks for that. It was fitted, I assume, with the boiler which was around 2.5-3 years ago. I always felt the shower was really powerful when I first moved in and somewhat hurt the skin...just dont know whether im used to it now but it certainly isnt powerful. dancinplumba - just wondered why a boiler would be designed to not utilise full mains power and require a reducing valve - is this normal?

just had a look at the manual and the max outlet pressure of the hot is max at 2bar so even if you bring the pressure up it will only come out at 2bar

if you wanted to get the full out of your main i would suggest going with an unvented cylinder and new boiler (not combined)

but first port of call would be to get a g3 engineer to check the system might be a line filter half blocked etc

 

[ecswtrav]

Thank you again - im assuming the extra power I get must be the cold water increase then rather than the hot - which is pointless!
When you say filter - do you mean the one in the PRV? I was debating getting a new PRV - maybe one that is preset. Either way I'll get in touch with a G3 engineer and see if there is anything obvious wrong and get things flowing a bit bette

 

[AWheating]

If your unvented set up was serviced correctly by somebody who knows what they are doing and g3 qualified they would have checked the prv was set correcctly, the strainer was clear, and all other safety devices were working as designed on the service.

 

[dancinplumba]

Diy