DIY boiler installation

22 Sep 2009
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United Kingdom
After reading up on various regulations, their does not appear to be any reason why a competent DIY person can not carry out the relevant preparation works and replace their own boiler. the Gas conection, commissioning along with the flue installation will however have to be carried out by a Gas Safe registered person

In my case I intend replacing the existing floor mounted boiler from a pumped heat and gravity fed hot water system with a Vaillant 630 wall mounted system boiler which i believe will be relatively strait forward

Any reason why a competent DIY person should not carry out this work or advise on any tips
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Any reason why a competent DIY person should not carry out this work


before you do anything tho drain and refill the system at least a couple of times

then add a decent cleaner for a while

then repeat

i assume this is a follow on to your power flushing post :?:

crap in the system has to be one of the biggest killers of boilers (regardless of the make / cost)

so get it clean before you start ;)
Would I be correct in saying all the pumps, valves, expansion vessel required to convert a gravity heated hot water, vented system to a fully pump sealed system, will allready be incorperted within the system boiler unit
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The pump and expansion vessel will be. but not the 3port valve etc.

Personally I would be looking at a heat only boiler and adding the pump etc to a standard Y plan system.
I would advise that you have a shop around to check that you will actually be able to get a gassafe installer who will be willing to complete and sign off your handiwork.
I have done numerous DIY boiler installation jobs and to be frank, it can be a lot more hassle than it's worth, especially if the boiler breaks down and you will find it hard to find a gas fitter that will connect and commission a boiler that someone else has fitted. My main problem was finding a gas fitter that could understand anything more than the most basic boiler controls.
Tony, how is a DIYer deamed to be competent? I am not being rude or cheeky but competance is not self claimed but proven in an exam
experience can also play a part in competence.

who is more competent a fresh faced 16year old with an ACS ticket or someone with 20years in the job but no paperwork. :?:
We've been through the competence argument too many times now. If the op is prepared to take responsibility for the wet side of it and possibly the electrics, then if he follows the MI to the letter and can get a rgi to finish, then that's up to him. It depends entirely on finding someone who is willing to complete the install.

I would find someone and folow theer advice if I were him, thus the "safe" part of the installation would be under supervision.

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