Combi Safety Valve

[jamesy]

Hello

I am installing a vokera compact 28 and am not 100% sure what to connect the pressure relief safety valve to. Any Ideas?

Before you ask I am getting a Corgi registered installer to connect the gas and commision the boiler.

Help appreciated.

 

[Gees]

If you mean the high pressure release outlet? that should be vented to the outside of the building where it wont spray boiling hot water over anyone if the valve should open.
Was it not in the instructions cos it usually is?

 

[ChrisR]

As above but you should use a couple of elbows to turn the end of the pipe back to the wall, assuming you can't take it to a gully drain or similar to point down.

In short it's agin the law to install your own boiler. Touching the flue is specifically verboten. If you're going ahead anyway, get a corgi to scan your plan before you start. Could save you making a small but vital/annoying mistake. You might just trash your boiler or get lousy performance, and no guarantee, in spite of it being commissioned to the book. There's nothing about commissioning which confirms that the boiler is safe to use, let alone sensible to use!

 

[COG]

Your pressure relief point can not rise from the boiler unless a tundish is fitted, the idea is that if any water is trapped in the pipe it may freeze and stop the "pressure blowing off".PS there is no health and safety LAW that says you cannot install your own boiler,as long as its done with competense and you seek no reward or favour (dont charge at all).who ever commissions your intallation is technicaly responsable for its standard if he passes it,not many people would be willing to do that if they are doing it propperly.

 

[Gees]

Cog... whats a tundish????

 

[ChrisR]

A tundish is on open connector, with the feed pipe over a thing like a funnel. There is no regulation about tundishes and prv pipes- it's down to the manufacturer.

Anyone who does any work at all on a boiler has to be "competent" under the law. Unless you have been trained and tested, you aren't competent. There will be things you never imagined you had to know.

Commissioning is not a legally defined term. There is a paragraph in the instructions, sure, but it does not cover all aspects of the installation, and does not confirm anything not specified in that paragraph. For instance there's usually nothing about vent pipes. But you could have an explosion if the "installer" got it wrong.

As COG says, there are legal traps here which many will not toy with.

 

[COG]

I spend 40 hours aweek following so called "competent " corgi reg fitters, i much prefer a DIY fitter who has the competence to read and follow instructions as aposed to a competent fitter going strait at it. .Any way ill get of my soap box ,pressure relief valve pipe should go to a point of safety as chris said without risk of blockedge or frost .PS If any one wants a CORGI eng they should check he /she has the current and relevent sections on his card ,not just a sticker on his van

 

[Gees]

Cheers COG that makes me feel a lot better. I have installed my last two boilers without any problems at all . the instructions are very clear. All I used a corgi man for was to commision the things.
By the way I'm an engineer by trade and will try ANYTHING ( Once)

 

[jamesy]

Thanks for all the very useful info.

there is a path right below the wall where my boiler is. I assume this means that I cannot just leave an open end to here.

There is a 40mm drain from the Kitchen running through the room. Can I connect in to this? And if I can does anyone know how.

Thanks a lot

 

[MANDATE]

My pressure relief valve pipe (15 mm copper) passes through a external wall, protrudes about 30 mm which is fitted with a elbow (downward) and short piece of pipe and another elbow so open end is facing and about 10 mm from wall

 

[ChrisR]

This prv pipe question is one of the things which is nothing to do with commissioning or being corgi registered! It's also a case where the rules aren't very explicit so you're safest to go with what the "industry" accepts as standard.

No you can't go to a 40mm plastic drain pipe The pipe isn't rated for steam, apart from anything else!. Into a ground gulley is ok though, if the end is visible.
If over a path, take the pipe right down to the ground and stop just short of the concrete. Not ideal but probably about the best you can do.
Turning back the end of a prv pipe is one of the standard things that gets done though it isn't in any regulation or manufacturer's instruction I've ever seen.
You have to ask yourself what would happen if the thing was shooting steam & boiling water out, enough to go 10 feet or so. I can confirm that it's quite dramatic!

MOST stuff is in the instructions these days and most boilers are simple to install, but accidents do happen and people do get fined and/or go to prison. Saying you did it and it was OK is a bit like saying you crossed a road without looking and survived so there's no need to look next time! There's the insurance thing too - if it fell off the wall and someone was hurt, I'm insured and it would be negligence if the screws were too short. If a DIYer did the same it would be criminal negligence, along with the Gas law infringements (I repeat you aren't allowed to do ANY WORK on a boiler, not just any GAS work..). Diy'ers have gone to prison for that sort of thing. And if it blew up and took your house with it, your insurance wouldn't pay up. Who commissioned it would be irrelevant.

 

[Gees]

(I repeat you aren't allowed to do ANY WORK on a boiler) ( ChrisR )

I've looked hard at the regs but can not see any reference to the actual plumbing bits... only the gas bits.

What paragraph says that it is illegal for me to do my own plumbing??

 

[masona]

ChrisR,

As above.....

Are you also saying we can't renew the thermo-coupling on the boiler unless you're Corgi registered ?

 

[breezer]

sorry to be a pain, but i think this says that you cant touch any gas appliance unless registerd
but it did seem a bit long winded, and i know nothing about it (so don't ask, i only found it)

 

[ChrisR]

Yes that's the GSIUR which applies.

Where it says "member of a class of persons" or something it means corgi cos that's the ONLY class recognised.

"Are you also saying we can't renew the thermo-coupling on the boiler unless you're Corgi registered ?"
If its your own boiler you don't have to be Corgi, ony "competent". which is where we got to above.
A thermocouple has to let go within a certain time depending on the appliance. Hands up anyone NOT corgi reg who has come across how long it should be!! A tc's job is to STOP the gas when appropriate, so the fact that the boiler works says nothing.

There was a time when corgi were saying you couldn't replace a pump on a central heating system, which is obviously stupid. Now they "allow" you to change eg a pump on a combi (inside the outer case of the appliance), which goes against the GSIUR. NB corgi have absolutely no authority to decide!. Now they say its ok to do things other than install appliances, or touch gas bits, any safety bits (which covers most) , or flues (inc fans etc). NB the cover of a room sealed combustion chamber is a safety item.

Surveys on whether sales of tc's etc should be restricted have been done - basically the public isn't bothered , and the HSE isn't bothered because not enough people die. It's about 40 a year total, so nothing compared to road deaths, and you can buy and fit your own brake parts etc.