commercial prv V`s domestic...

[Barry98]

both in cellars

how come on commercial installs i see prv`s discharge pipe terminated about an inch above the floor.

but you can not do this on domestric ?

just a random saturday afternoon thought


lol

 

[SafeGasInstall]

you mean comes out 1" above floor and facing down ,why not in domestic ? you can terminate prv just like discharge pipe from D2 up to 100 mm from floor level and then guard it ! I have install boiler on first floor flat then prv comes out and runs down the wall to about 100mm from floor level

 

[GQuigley67]

is it because its a plant room which has a floor gully ?? we done it this way and we got pulled on 1 job where they wanted it all T'ing into 2" copper discharging over gully. Was a total nightmare and was at end of contract so we didnt do it lol no doubt our snaggin guy had to do it

 

[Barry98]

ooo was led to belive this was a no no in domestic o well learn something new every day

 

[Barry98]

is it because its a plant room which has a floor gully ?? we done it this way and we got pulled on 1 job where they wanted it all T'ing into 2" copper discharging over gully. Was a total nightmare and was at end of contract so we didnt do it lol no doubt our snaggin guy had to do it

i dont recall seeing a gully this was in a hotel in blackpool it where everything had a pump of some sort to get it back up above ground with the exception of the prv pipe, just had me thinking thats all

 

[SafeGasInstall]

you just had 666 post mate

 

[SafeGasInstall]

keep it there dont post

 

[wasbod]

ok i wont

 

[GrahamM]

This was a question I meant to ask some time ago to clarify, but slipped my mind.
I was at a year old Greenstar in a basement where the PRV terminated at outside ground level facing down at about 10mm from ground.
It was obviously terminating safely but it was in my head about Unvented D2 discharge having to terminate a minimum of 70mm from the ground and I second guessed myself if there was minimum height above ground for a standard boiler PRV termination. All I was aware of is that it must terminate outside in a safe manner so as not to become a danger/nuisance to people or property.

 

[SafeGasInstall]

"All I was aware of is that it must terminate outside in a safe manner so as not to become a danger/nuisance to people or property."

this is exactly the same as my understanding ,lets see what kirk has got to say about this

 

[Dotty]

Had a health and safety moron ranting and raving at me the other week because the discharge pipes off the twin prv's on a trio of 800kw boilers were going up and out the wall of the boilerhouse at high level.

I let him carry on in this vein for some time, listening intently as he threatened to report me for allowing such a dangerous installation to remain in place.

Then I asked him if he knew what a Medium Temp Hot Water System was............

 

[Barry98]

this is bugging me now ive just read on another forum that a prv pipe can run up 1 meter and then go outside. has anyone else heard this, this is a new 1 on me never knew anything about 1 mtr certainly not in any of my books

 

[Gray0689]

Can say ever heard of that mate

 

[SafeGasInstall]

have seen a hall street done by the cancel ,prv terminating about 4" to the left or right of the flue !
i was shock ,but might be to do that all different cancels have different specification of work

 

[Barry98]

id ring gas safe tech but well ya know

 

[mikegas]

this is bugging me now ive just read on another forum that a prv pipe can run up 1 meter and then go outside. has anyone else heard this, this is a new 1 on me never knew anything about 1 mtr certainly not in any of my books

Think this might be if you fit the prv external from the boiler Vaillant do something like this

 

[Barry98]

tbh am struggling to find something concrete on this , its one of those things you know but dont know why.lol

i really didnt not think you could fit a domestic boiler in the cellar of an house then run the prv pipe up the side of the boiler and drill at the same height as the flue and then put it outside. i dont know why buy hey ho.

 

[mikegas]

I went on a course at Vaillant recently and he showed us an Eco tec that had the external prv kit fitted with pipe work running up the side of the boiler 1m

 

[SafeGasInstall]

Think this might be if you fit the prv external from the boiler Vaillant do something like this

they do a prv 2 bar what you do you cap off the one under boiler and tee of the return as near as possible to the boiler and then you can run prv up 3 m ,this is for boilers in basement

 

[Barry98]

ive just been reminded of one i did years , upon years ago with my mentor by reading another post on hear he fitted a tundish i think. i think this where my memory is telling me it cannot go up and out

 

[GrahamM]

As far as I recall the last few MI's I read, including Vaillant state "PRV pipe must be short as possible, run with a continuous fall, and terminate safely etc...."
It is a safety device that must run off water quickly and safely and like any drain must have a continuous fall. How can this important factor be any different?
I know some manufacturers may let you fit in a secondary PRV to the return for certain circumstances but as far as am aware this must still be piped with a continuous fall.

 

[Barry98]

and gas safe`s reply was drum roll please



speak to the Manufacturer , lol

like the monoply get out of jail free card

 

[emerald]

i was talking to a plumber about this the other day and he said that if you couldnt get a fall from the PRV then it is acceptable to tee it back into the heating pipework below the boiler, and fit a 2nd PRV to the heating system at a higher level,

personally i wouldnt do this but what you guys think?

 

[stevetheplumber]

they do a prv 2 bar what you do you cap off the one under boiler and tee of the return as near as possible to the boiler and then you can run prv up 3 m ,this is for boilers in basement

cant see how that is safe if someone closed the iso valves no prv in heating circuit why do they suppply 2 bar insted of 3?
on the oldervaliants you could unscrew the prv and pie it at high level

 

[SafeGasInstall]

hi Steve ,is 2 bar and is tee from near as possibly on the return to boiler ,then 15 mm runs up and at point of exit building with stickers showing it is the location of prv is design to be use when you have boilers in cellar or basement