Quick pressure relief valve question

[Anders0n]

PRV has gone on a WB 28i Junior Combi, it's pretty much fully open, heating is drained for now.

Looks a bit of a fiddly job to replace it, could I just put a new one on the relief pipework immediately after the valve?

I'm struggling to think how it wouldn't work?

 

[leelister6]

That would constitute tampering with a safety device on a gas appliance. Get someone in who can do "fiddly" jobs

 

[Anders0n]

So would it work or would it not work? Or do you not know?

 

[PlumbBobBob]

there's no point because the original one will still be leaking get someone qualified in to fix it properly.

 

[Anders0n]

Yes the original will still be leaking but only up to the new one about 2 inches away, so the CH system will still have a 3 Bar pressure relief.

And I am qualified.

 

[PlumbBobBob]

it may have a 3bar pressure relief but you wont get it up to pressure because of the leaking prv

 

[Shaunthegas]

Should really change the existing valve. Yeah it would work having one further down.
But you've identified a faulty safety device, so good practice to change like for like

 

[Anders0n]

it may have a 3bar pressure relief but you wont get it up to pressure because of the leaking prv

I'm not understanding you, the water coming through the leaking prv would just stop at the next one?

 

[Anders0n]

Should really change the existing valve. Yeah it would work having one further down.
But you've identified a faulty safety device, so good practice to change like for like

Yeah in an ideal world I'd change it. But this is a job for a builder, and he's unlikely to be willing to pay for me to take the whole hydraulic block out when I could fix it in 10 minutes.

 

[PlumbBobBob]

i don't think so. maybe we are at crossed purposes, surely there will still be an open pipe with the leaking prv

 

[GQuigley67]

re-read post so changing my answer

it would work but best speaking with manufacturer first

 

[Shaunthegas]

In that case it's your call. It won't take that long to do anyway, hour tops. I would imagine Worcester will tell u to change like for like, and personally I would inform the builder it is as specified. Sounds like a generic cop out answer, but end of the day it's your ticket not his.
Be worth doubling checking with WB, but we both know what they'll say.

 

[Anders0n]

It's not that big of a deal, I'll fit the new PRV and test it so I know it works.

Nothing will be unsafe so nobodies ticket will be on the line.

 

[Jonwells]

Greenstar prvs are tricky, but when you drop the clear plastic cup (as when you install the boiler), pull out the cir clip the prv comes out, last one I did, I removed the cold supply pipe, it made it easier, watch however, I fitted a bosch replacement and it was supplied with wrong O ring, so seeped when boiler got to 1 1/2 bar, I wasn't happy. Jon

 

[HHP Ed]

do you guys not just take the boiler off the wall? its so much easier. thats if im thinking of the right worcester

 

[mitchellplumber]

I take it, By saying the PRV is "leaking" you mean "passing"
I think this is where the confusion is. There should be obstruction on a safety discharge pipe, the pipe must also take the shortest most direct route. Therefor you can not fit a PRV after a PRV.

Hope this helps :0)

 

[mitchellplumber]

*no obstruction* sorry about that :0)

 

[arran197]

Best to change it really. Worcester will tell you to remove the whole lot of the hydrolics. I was on a course there a few weeks back. I haven't ever done it thought, so don't know how difficult it actually is.

 

[Destroyer2813]

Only taken one Hydrolic block out to change a dhw heat exchanger on a junior pain in the arse about half way through thought to myself why didnt i just take the boiler off the wall ( granted my be easier if youve done a few)

 

[GQuigley67]

i'm not a fan of worcesters, i've only fitted the juniors before but dont like them they are a pain to install

 

[Destroyer2813]

I dont find them difficult at all GQuigley, what u find a pain on em?

 

[GQuigley67]

compared to other boilers they are a pain to install and take longer, at the moment I'm fitting alot of logics on contract and they are a doddle, I find Vaillant boilers easy also to install.

 

[Destroyer2813]

Fair enough its all i install so speed through them on install

 

[jncalderc]

It will work however how do you know what caused the PRV to open wont cause it to Jam up again. Tell the builder the problem, they are normally understanding and readily reach for their wallets when enlightened as to the difficulty you face

 

[GasManMike]

Some manufacturers will let you cap off the existing PRV and fit a 'remote' one (Vaillant), so dont think its tampering with a safety device as long as there is a PRV on the return as close as poss to the boiler with a clear run of pipe between the two. Check with Worcester see what they say that should clear it up.