MIL's New Boiler

18 Oct 2006
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United Kingdom
Went up to the mother in laws yesterday - not been up for some time.

She has had a new boiler fitted - Multipoint replacing a system boiler and having looked at the installation I have a couple of queries:
1. The boiler (glowwork 30...) is fed by a 15mm pipe - is this likely to be big enough?

2. Compression fitting in the gas feed - are these allowed?

Not been given a test certificate yet - stressed to BIL who lives with her that he must insist on one and also ask for the installatio/commissioning test results.
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I assume you mean the cold inlet is 15mm? Yes that is standard. If you mean gas then it should only be for about the first 300mm off the boiler.

Compression fittings are ok as long as they are accessible and visible all the tim.

Vaillants come with the gas connection on the boiler in compression
No - the gas supply is 15mm, the new pipe run is about 3 feet to where it joins the old copper pipe. 3 more feet and it disapears into the ceiling!

Does visible all the time mean you cannot box it in?

Old boiler was much lower output.

Also the thermostat is fed by only two wires - does not look like 240v cable (both black and no earth) - not sure if it is low voltage but is this usual.
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The pipe sounds like it's bound to be undersized and not supplying enough gas-a working pressure test at the boiler should have been carried out along with other tests and should be put on the benchmark and installation paperwork.

You cannot box in a gas pipe with compression joint fitted.

Some room thermostats will use only two wires.

Insist the guy returns to fill out the benchmark cert/installation paperwork. ;)

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