pushfit are they reliable?

[IMM]

You are right: again..

What do you expect from plumbers. Non-barrier is fine in an open vented system, but should not be used in a sealed system.

[IMM]

I don't document every horror story installers tell me, and I have heard a few of them.

[Mike Harrison]

I have never used pushfit but would have some reservations about long-term reliability - most non-metals do deteriorate over time, especially when hot. I would also worry about the effects of repeated expand/contract cycles on CH pipes.

Soldered fittings are not all that difficult to do, and cheaper - I would go for soldered for peace of mind if installing in a house I intended to still be in after 10,20+ years' time.

[David]

In article , IMM writes

Yeah sure, with your hatred of plastic systems you would get a sworn testimony from each and every one and insist they join the group so they could support you, look how you've hung on to the one or two problems that have been reported here

[David]

In article , IMM writes

that was cruel Andy, you know he can't work these out

[Andy Hall]

No. The issue is not between open and sealed CH systems (both should use barrier pipe) but between CH systems and DHW/potable water.

.andy

To email, substitute .nospam with .gl

[Andy Hall]

Ah I see. Hearsay.

.andy

To email, substitute .nospam with .gl

[David]

In article , IMM writes

I've never had a failure yet in my 97 years as a plumbing heating designing engineer

[David]

In article , IMM writes

I don't know if that's good advice, I think my house was plumbed with cheap imported copper pipe which is why I'm getting pinholes appearing. I would pay a bit more and get better quality, its worth it in the long term, unless you buy two cheap heating/water systems and if one fails use the other one, simple!

[Grunff]

Lada's what?

[JohnnyEnglish]

Abuse reported to apostrophe protection society.

[Ed Sirett]

I cannot but suspect that this issue aboutoxygen diffusion is a complete red herring put about by BG for there own reasons. [1] Although I have no data to hand for oxygen diffusion rates through >1mm of plastic, ot does seem counter intuitive that oxygen could diffuse into water under pressure from outside.

All this has to be set against the oxygen diffusion that possible with a F&E tank.

Anyone got soem real data around, is the Hepworths advisor about?

[1] There might be a number of reaons for this: A) BG workforce conservatism. B) Possible greater reveue from selling a new installation. C) Possible greater realiability by forcing a replacement of the system.

[Ed Sirett]

There no mention of armatures in the sales leaflet so how could he.

[Andy Hall]

It is a real phenomenon.

For example, there is an ISO standard in progress on its measurement.

does seem counterintuitive that oxygen would diffuse through plastic when the mechanical pressure on one side is higher than the other.

However, the phenomenon is going on at a molecular level and is related to concentrations rather than mechanical pressure..

Diffusion is basically the tendency of molecules to move from an area of higher concentration to one of lower concentration. The oxygen diffuses through because the concentration of molecules in the air is less than that in the water.

Many types of plastic have a very large molecule in comparison to oxygen which increases the diffusion rate. There are even specific plastics for biological and medical purposes (e.g. dialysis) designed to maximise diffusion - e.g.

To email, substitute .nospam with .gl

[Earl Kella]

----- Original Message ----- From: "mark al" Newsgroups: uk.d-i-y Sent: Saturday, November 29, 2003 12:10 AM Subject: pushfit are they reliable?

I started doing my CH 'properly' using mix of soldered and compression. After trying out a couple of speedfits recommended by the guy in the Plumb Centre I did the rest using these.

It is just Sooooo much easier and quicker and you have a certain amount of movement that you don't get with the solder of compression joints.

It works out more expensive but I think it's worth it. BTW, the only joints I have ever had leak have been compression joints when not tightened properly. My fault I know, but they seem to be the weak factor in any plumbing work I do so I try to avoid them.

Regards

Earl

[BillR]

Yes. I've used them for years without any problems. Avoid the real cheap ones and follow the instructions rigidly. The seal largely comes from O rings and problems occur if these get damaged because of rough pipe ends or whatever.

[BillR]

I can't aggree with that. Hep2O are one of the best in my opinion.

[PoP]

Crikey! Still working at 115? ;)

PoP

[IMM]

...the witful David says....

..is it the way he tells em?...

[IMM]

He used to install slate tanks....probably still does.