Replacement CH boiler - internal plumbing plastic?

Might be worth checking the installation instructions, many stipulate that pipes close to the boiler must be in copper.

Thanks John - bit niave not read ALL parts of the instruction book fully first. This categorically says NO .

My self argument in its favour was that if there was a fire in the boiler itself then this would be a self extinguishing feature, but further thought suggests that the continuous local heat would soften the plastic pipe and its couplings. Thanks Rob

With some flex in the plastic, the copper does not have to be quite so accurate.

From next month you should be able to get some fincancial support for a new boiler from the government. Getting the grant for a DIY install may be a challenge but if you do manage I would certainly like to know!

Yup I think that is the usual thinking - the pressure handling capability of plastic decreases with temperature. Not usually an issues at DHW temps, but boiler primary flow temps may be higher, and sealed system pressures could go up to 3 bar or more.

That would negate the point of him doing it. Its the return side but still might be very hot I guess. I'm a bit old school having had many friends where modern installations using plastic have had leaks and strange effects due to plastic pliability mixed with the metal used for other parts of their systems. The more I read here about CH systems the less inclined I am to have one! Brian

Zero chance of getting a grant for DIY I would have thought. These grants are paid direct to a "professional installer" who also has to be registered on the relevant scheme and/or a member of a relevant professional body and/or safety organisation.

We had our boiler replaced under some such scheme using a "professional installer". This "professional" installed the magnetic filter thing with the flow going the wrong way. Terminated the flue below and too close to an opening window. Cracked the internal condensate reservoir/trap so it leaked.

The first two they sorted out after an inspection, the cracked condensate trap I had to sort via the boilers warranty.

I do wish there was a DIY option for these schemes but I can understand why there isn't.

This inside the boiler? Have you ever seen a boiler with internal plastic pipes?

To be fair, I find bending copper with a proper pipe bender ones of life's simple pleasures.

This is an outside oil boiler replacement that I was able to buy at a trade discount intending to fit myself as I 'd done its predecessor 25 years ago.

Circumstances arose that It would be better getting someone to do it so I got a quote which was so delayed that I had gone ahead and taken the old one out with some friendly assistance, and asked for an adjustment to the quote and what about the condensate, at which point they baled out. I now realise that perhaps someone had realised that they were going to lose money on this or it would have been a very shoddy job. Grant Boilers are going to get a letter of complaint from me for poor quality design which has lead to all sorts of complications. It's all very well Which? recommending them bu they don't do an installation.

Rob

I have seen boilers with plastic O-rings that got hot, distorted and then leaked.

You seem easily pleased.

Something I've never seen a professional do. And the result looks messy.

Only if you use too much tape. It should be hidden under the compression nut.

The word "should" ought to be associated with *"should* not wrap PTFE around an olive".

PTFE creeps.

If you want lubrication, use a lubricant.