Remote Pressure Relief Valves

[Dan Masey]

Has anybody fitted one of these in the past? Im just curious on how they work. Normally used when prv p discharge pipe cannot take a easy downward fall outside from the boiler. Does this just tee into the heating circuit at a more convenient place? Do you need access to it? i.e it cannot be under the floor?

 

[Ermintrude]

HA just fit them on rad leg above floor..... Looks lovely

 

[Scott_D]

You link the prv pipe into the heating then fit the remote valve with no valves in between. I think I have a technical email from ideal.
I can forward it if you pm me your email address

 

[lame plumber]

remember to label the boiler where it could have gone as to where it actually is, and it must be accessable, how would u feel trying to replace a hidden one?

 

[Ermintrude]

You link the prv pipe into the heating then fit the remote valve with no valves in between. I think I have a technical email from ideal.
I can forward it if you pm me your email address

Link back in?? Why not remove valve and blank off ?

 

[Scott_D]

Because you would need to remove the valves on the boiler

The built in prv will discharge into the heating pipe work. The pressure will then increase enough to set off the remote prv.

If you blank off the built in prv the boiler isolation valves could be closed creating a potential problem.

 

[happyflyer]

Because you would need to remove the valves on the boiler

The built in prv will discharge into the heating pipe work. The pressure will then increase enough to set off the remote prv.

If you blank off the built in prv the boiler isolation valves could be closed creating a potential problem.

Scott,

I don't understand this, isn't the pressure the same in the boiler as it is in the system all the time, the PRV won't blow beacasue it is not discharging
to atmosphere or have I misunderstood. Not certain there is a law that says it should always be next to the heat source but that is where I would always put
it unless it is impossible, if the flue can go through the wall why can't the PRV pipe do the same, "Confused"

Tony

PS it's my age, I need a sketch, photo or drawing these days

 

[Dan Masey]

I know the vaillant remote prv is set at 2 bar, isn't this less than the built in prv on the boiler which is around 3bar??

 

[Scott_D]

The prv is a safety device covering the boiler. Imagine the expansion vessel was dead and the boiler valves were shut and due to a fault the boiler kept heating then boiling the water. The pressure would quickly rise and with no prv something would have to give, probably the water would just leak out but worst case the boiler would explode.

The prv doesn't need to be next to the heat source but it shouldn't have a valve between it and the heat source. The built in prv linked into the heating pipe work will bypass the boiler valves.

I would be happy to send on the info I have if your send me your email address.

The Vaillant kit is probably set lower as the remote prv is ment to go at a high point(loft etc) and if the boiler was on the ground floor or in the basement the pressure difference could be the 1bar

 

[Ermintrude]

Makes sense.

 

[Dan Masey]

Yea that's clearer. Ie both the 2 port valves are closed but the boiler keeps heating (for some reason) and the remote PRV is after the 2 ports.

 

[HTG-Apprentice]

because you would need to remove the valves on the boiler

the built in prv will discharge into the heating pipe work. The pressure will then increase enough to set off the remote prv.

If you blank off the built in prv the boiler isolation valves could be closed creating a potential problem.

kaboom!

 

[Rickster123]

Having an argument at work at the moment with a subby who's taken the prv up from the boiler in an airing cupboard and out of the gable end of the loft space.

 

[Ermintrude]

Having an argument at work at the moment with a subby who's taken the prv up from the boiler in an airing cupboard and out of the gable end of the loft space.

What u arguing about? Who's van is better? ....... Defective work, off site!

 

[happyflyer]

Having an argument at work at the moment with a subby who's taken the prv up from the boiler in an airing cupboard and out of the gable end of the loft space.

I would make him take it out too, no need for that, if it froze up where would you be, if it ever blew off or was tested it would be full of water 24 x 7, he's a lazy sod, he would be down the road, get a new subby who understands or fit a bigger pump, that appears to be a cure all! :mad2: he doesn't give a toss how much pipe he uses, you are paying for it.