Using flexible hoses to gas water heater?

[T i m]

Hi All,

I'm replacing our own Main Avon multipoint water heater with a newer Main Medway jobby.

Of course all three pipe connections (cold mains pressure water in, hot mains pressure water out and gas in) are in different places. Doh!

So, I can either move them all in soldered copper, use compression copper fittings or for the water at least use flexible tap connectors? (Can they also be used for gas out of interest .. considering much gas plumbing is in plastic these days (in the road at least!)) ;-)

Based on the fact we have the flexible connectors at the other end of the system (on the sink, basin and bath) and they are obviously able to do the job (heat and pressure) but are there any rules prohibiting their use at the heater end, or does anyone have general thoughts re using them for such please? FWIW I think I've seen them used to connect a combi boiler but that doesn't mean such is 'good practice'?

All the best ..

T i m

[John Stumbles]

...

They're absolutely prohibited for gas use. To be honest it really doesn't sound as if you have the competence to do this job if you're asking questions like this. I suggest you get in a qualified (i.e. CORGI) fitter to ensure the gas pipework, ventilation and flueing are sound. They may be happy for you to DIY non-gas parts of the work but if it were me I'd want to be involved from the outset rather than asked to come in and sign off someone else's work.

[T i m]

Ok, thanks (I'd guessed as much) and why I phrased it like I did. But fine for the water heater connectors though John? I was more unsure about the flow rate but as they are already elsewhere in the system I'm not sure it's that relevant? Are there some that offer less resistance (for the same nominal connection size) would you know please? The bottom line is final flow rate is probably more a function of the heater stat than any pipework.

You are probably right. However I did re-plumb (water and gas) and wire this house when I bought it ~30 years ago and it's all been ok so far (could just be just luck I guess)? ;-)

Yeah, I helped one of them bleed his radiator .. he'd been on it an hour apparently! ;-)

It's my house and trust me, there is no one more keen to ensure all those points are correct than I am. BTW, I've ordered a new flue and case seal, just because.

As it happens he will be here for all the key stages (he's just not about today) .. like I said, I want it right .. ;-)

All the best ..

T i m

[Tournifreak]

Out of interest, *why* are flexible water hoses absolutely prohibited for gas connections? As Tim said, they can easily handle the pressure. Except in the event of a fire, they could easily handle the temperature too... Ah, perhaps I've just answered my own question...? Jon.

[T i m]

The plastic pipe bringing gas into my house (above ground) doesn't look that special Jon?

I agree the fire thing is the most likely reason.

I was also half expecting a "yes you can but you have to use a BS1234/Z fireproof one" as gear seems to move at such a rate these days.

All the best ..

T i m

[geoff]

I dunno, I wouldn't have known this when I was looking to install my first boiler

[geoff]

In message , T i m writes

Personally, I'd just do a proper job and have done with it

Actually Ed can only be a few miles down the road from you if you want your gas connection done and tested ...

[geoff]

In message , geoff writes

Which reminds me

when my brother moved into his last house, the gas cooker was connected to the main via a bit of garden hose and a couple of jubilee clips

[John Stumbles]

Because they're not approved for gas (specifically natural gas in this case). *Any* fitting not approved for gas is prohibited. It's regulation something or other in the Gas Safety Installation & Use Regs.

As for suitability for the purpose, garden hose would probably also do to convey gas, but there are various possible failure modes which would cause danger such as the material perishing over time or under the influence of stuff in the gas, or heat etc. Basically the legal position is a presumtion of un-safety unless proved and certified otherwise.

[<me9]

So I won't be able to use my old bunsen burner stored in the loft? It was OK

45 years ago.

[T i m]

As will I .. I was only asking out of interest.

Thanks for the suggestion Geoff but I have a CORGI guy on hand for all the important bits. Plus the new flue and case seals won't be in till Wednesday so there's no rush etc.

In fact it gives me time to move the water pipes about etc.

All the best ..

T i m

[John Stumbles]

You might want to put a new hose on it :-)

And I'm not sure what you'd connect it to - those push-on tapered & ribbed gas taps we used to have on lab benches at school would surely not be legal today. Still there must be provision for it somewhere in the regs or chem labs would be out of business. There's even a provision that allows you to do a gas installation in ways that would contravene the regs except that it's in a workshop where gas fitters are taught gas safety.

[T i m]

In the real world Geoff there are loads of things that are just bureaucracy. I know John means well and there is no way I will be doing anything against code but the point is there are probably loads of things in millions of installations that wouldn't meet today's code but are *still* perfectly safe.

That's not to say they couldn't be made better or safer but you only have to see what they *still* get away with in other parts of the world (and closer to home when they think no one is looking) to know that folk get away with all sorts of stuff.

It's not in my nature to try to 'get away' with anything .. being Mr over cautious or over engineered (or over fussy), but I know where to draw the line and I can use common sense.

Our daughter has a small wall mounted balanced flue fire in her room and the thermocouple has just failed. I've removed the thermocouple (new one will be in tomorrow) but I could have taken one out of the brand new fire I still have sitting in it's box. I didn't because I see no point disturbing a new fire for the sake of a few hours. I could have (easily) changed the whole fire but that would mean touching the gas and I wouldn't want to do that! ;-)

All the best ..

T i m

[Andy Hall]

That's really disappointing. It used to be great fun to fill sandwich bags wth gas and some residual air and light it. That and just lighting the gas coming from the tap itself. Some had quite a bit of oomph.

I think they are, aren't they as far as schools are concerned?

Is there a kind of initiation ceremony? You know, trouser legs rolled up, that kind of thing.....

[Bob Mannix]

He never said you wouldn't be able to do this or the OP wouldn't be able to use flexible connectors. He said they were prohibited, which they are, with all the attendant legal (and, possibly but not necessarily, non-obvious safety risks). We are all able to do more than 30 in a 30MPH zone but it's prohibited. If you fancy trying your old bunsen burner, carry on (just don't ask if it's legal!)

[Rod]

No - it won't have been converted for North Sea Gas!

When the bunsens at my school were converted, there was a shortage of replacements. So the staff rammed bits of wire into the jets at the base of the ones and we all used them.

When corgis were the Queen's dogs...

[dennis]

I must try that again now my dad has an oxygen concentrator.. booOOOOOM

[Andrew Gabriel]

Another reason is that you aren't allowed to use flexible hose to connect a gas appliance with a fixed flue, because it might allow the appliance to be operated in a position with the flue disconnected.

[T i m]

Whilst I can see the point to that I'm not sure in many instances would doing so be possible, even with flexible hoses on the water etc.

Ok, I know it would *be possible* but I'm not sure the lack of a flexible gas connection would stop them in any case!

Ok, as an aside, what about those corrugated 'flexible' copper hoses (a smaller version of the one they use to connect the gas meter). I assume they would also not be permitted for the reason you just gave?

All the best ..

T i m

p.s. I still haven't had an answer re the use of the stainless braided flexible hoses for the water connections on this multipoint?

I'm pretty sure I've removed a boiler for a mate (it had all been decommissioned gas-wise) and that had all the water terminations made with such (15 and 22mm)? This doesn't mean it's a good thing of course, just that someone has used them for said.

[Doctor Drivel]

The "bendable" corrugated copper flexes can be used on gas. Using a water flexible connection is legal. There is nothing against any regulation that I know of that says they cannot be used at an appliance. One with an integral isolator would be the best bet.