Expansion vessel on a flexi - illegal?

[Ric2013]

Saw a photo a customer showed me of what seemed to be a flexi installed on an expansion vessel serving a small electric water heater by someone he found who was cheaper than me. I say 'seemed to be' because I'm not sure from the angle of the photo whether the flexi was attached to the vessel or elsewhere, possibly to the heater itself.

Can people with Level 3 or G3 registration please confirm whether flexis anywhere between a source of heat and the expansion vessel are absolutely wrong? Thank you.

 

[Pickwickpick]

Expansion vessels are normally attached with a braided hose.

 

[Riley]

Some unventeds come supplied with a 1/2”- 1/2” from hydro block to vessel

 

[Pickwickpick]

Firebird Expansion Vessel Flexi Hose, ACCCOMHOS | Buy at H.P.W.

Was it like the above?

 

[999]

There is flexible hoses available to buy used for the hotwater expansion into the vessal. Personally i like to pipe them up in copper

 

[ShaunCorbs]

they are allowed but not recommended

 

[townfanjon]

Always used to be connected by flexis but the trend now is to hard pipe them .

 

[Rob Foster]

Why would you deliberately build a weak link into a system ,
Copper is best centralheatking

 

[Ric2013]

Firebird Expansion Vessel Flexi Hose, ACCCOMHOS | Buy at H.P.W.

Was it like the above?

From the photo I saw of the install I couldn't tell the difference between a tap flexi and your one.

 

[Riley]

Maybe call manufacturer as the MIs will always win through

 

[Scott_D]

Why are they showing you if you didn’t get the job?

 

[Ric2013]

I don't know. I think he was being friendly. He likes to chat whenever he sees me, but his English isn't good, so showing me a photo aided communication.

To be honest, I wasn't happy with the last job I did for him, so don't blame him for shopping around. I put in the cheapest tap I could find that allegedly had a British Standard and was therefore legal to install in his kitchen because he didn't want to spend much (he is harder up than I am), but I didn't like it. I put it in with copper and wish, with hindsight, I'd used restrictive flexis, as the water issued violently from the tap.

 

[Welder]

Always used to be connected by flexis but the trend now is to hard pipe them .

I stopped using flexis years ago because they simply do not last. Hard pipe complete with a drain point and isolator for simple servicing

 

[Welder]

From the photo I saw of the install I couldn't tell the difference between a tap flexi and your one.

Because there isn't any! EPDM rubber hose the hose alone is not rated for the pressure. It's only the brading combined with the hose that gives it its rating. Beware. Hard pipe always best. There is now, I believe, a new super duper vessel hanging system too.

 

[Ric2013]

I stopped using flexis years ago because they simply do not last. Hard pipe complete with a drain point and isolator for simple servicing

Agreed. I meant from the point of view of attenuating flow.

Does anyone make something like this Flow Regulator Cartridges - 2.5 l/m- Isolating, Flow Control & Service | BES.co.uk | BES.co.uk that could go straight into the tap tail? Would save having to fit a specific brand of isolator just to be able to use said cartridge.

 

[Welder]

Agreed. I meant from the point of view of attenuating flow.

Does anyone make something like this Flow Regulator Cartridges - 2.5 l/m- Isolating, Flow Control & Service | BES.co.uk | BES.co.uk that could go straight into the tap tail? Would save having to fit a specific brand of isolator just to be able to use said cartridge.

None that I know of. The link you put up is always what I used.

 

[Rob Foster]

At the end of the day, whatever
Its obvious pressurised systems are just that and any weak links should be not be installed , regulations are ok but we the installers must set up the most safe systems ...thats my opinion
Rob Foster aka centrakheatking
Copper and hard plumbing is always best in this situation why
Argue otherwise

 

[Ric2013]

None that I know of. The link you put up is always what I used.

Cheers for that, although I've since had an interesting comment from BES:

We supply these for the flow regulator ball valves but I have had feed back from a customer saying they have put them directly into a tail to a shower and it worked. May be worth [a go] for the cost of them.


I'll play around with some at home, the place I usually try out experiments to see what actually works without inflicting it on customers. It may be worth seeing if these can be used in this way. Will report on findings.

 

[Welder]

Yes they do fit into a shower tail but they are much wider than a tap tail

 

[Rob Foster]

Cheers for that, although I've since had an interesting comment from BES:

We supply these for the flow regulator ball valves but I have had feed back from a customer saying they have put them directly into a tail to a shower and it worked. May be worth [a go] for the cost of them.


I'll play around with some at home, the place I usually try out experiments to see what actually works without inflicting it on customers. It may be worth seeing if these can be used in this way. Will report on findings.

Be aware Bes at Electric Avenue are discount retail,and wholesale outfit , very good but
Are not manufacturers and unable to,advise on serious matters like this

 

[Ric2013]

And it wasn't really advice if you read it carefully (it's very carefully qualified), but better than I get from Plumbase who sell me an immersion heater and tell me it's suited to a stainless cylinder and then when I read the instructions it clearly states 'this is for use in a copper cylinder only'.

Now I only trust manufacturers, and only when they put it in writing, and even then I'm sceptical, because most technical departments don't really have a clue; in fact I've spent more time studying the Honeywell ABV than anyone I've spoken to in Honeywell's technical department who only go off the limited information they have [in fairness, they did tell me how to strip it down and reassemble, which helped].

Even Mira doesn't have detailed information on the flow rates for all of its showers at a range of given operating pressures. Then they tell me 'there is a variety of factors' (no there aren't, not when I'm asking for the flow at a given operating pressure at the shower inlet).

Quite honestly, I prefer evidence based on real experience, hence perpetually lurking here.

 

[dan_the_plumber]

It’s a great thing to ask questions and I would recommend you keep on reading and reading and reading. Building regs, central heating compliance guide, water regs etc.
BTW your ‘violent tap’ issue. Could be solved with two ballafix turned to 45 degrees yo limit the flow

 

[Ric2013]

Well, I was under the impression that it was considered bad practice to half turn off a spherical isolator on the grounds that this tends to make them seize up? Prior to learning this, I did used to do just that! What's the truth now?

 

[Ric2013]

Update.

I tried fitting the restrictor in a 1/2" Francis Pegler tap tail and it seemed to fit perfectly in the bore, but the restrictor was too long for the bored-out length of tail. The restrictors work well when used as intended, but I can't say I'm especially fond of the valves they come with, though I find them acceptable.

 

[Kosta_matt]

There is flexible hoses available to buy used for the hotwater expansion into the vessal. Personally i like to pipe them up in copper

I have piped mine up in copper. It is leaking at the expansion vessel joint. I used a compression to female I think with ptfe. I cannot get it any tighter. Only a slow drip, but still a leak! Any suggestions. Thanks

 

[ShaunCorbs]

More ptfe around 15-20 wraps