Unvented cylinder to be installed

25 Jan 2009
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United Kingdom
Hi, I am looking for some advice if I may about a job I may be having done soon by a plumber.

I am thinking of having an Unvented hot water cylinder installed, called a megaflow, and it will give me mains pressure hot water.

The plumber is also going to make my cold water mains pressure at all taps, the shower and also at the toilet.

He reckons the job will take no more than 1 day. What he has told me he is doing is:

removing the cold water tank from the loft and associated pipework to and from it. Joining the megaflow to the mains cold water, the hot water will be taken from the top part of the megaflow, and joining the pipes from the boiler to the new megaflow cylinder to heat the water.

The central heating and boiler will remian the same as before.

The megaflow cylinder will sit in the airing cupbaord where the old hot water cylinder was, obviously the old one will go.

Apparently he needs to drill through my bathroom wall (through the airing cupboard) to run a combined pressure pipe or something, in case of a future fault with the cylinder! Don't know if this is required?

The cost which I have been told it will cost is: £1,950. Is this a good deal?

Any advice/info would be great...
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What does this cost include?
Whay are you using this plumber if you do not trust his advice and yes you will need a pressure/temp relief pipe.
To install unvented cylinders you need to be G3 certified so check he/she is.

I take it you have at least 20litres a min flow rate and 2+ bar presssure otherwise this exercise is pointless.

i am asking out of interest to see if i have a good deal!!

yes he did check the water pressure and flow with a gauge and some other device and said it's be better than my normal old cylinder, especially in the long run.

the cost is for everything, including all parts and labour, which he says will be only 1 day.
Well I am giving you good advice.
Bite his arm off at that price a bargain esp if he is installing a Magaflo cylinder.

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Well I am giving you good advice.
Bite his arm off at that price a bargain esp if he is installing a Magaflo cylinder.

Megaflo is a trade name for an expensive Heatrae Sadia product.

Is he installing a Megaflo, or is he using megaflo as a generic description for unvented cylinders, like some people call all vacuum cleaners "hoovers"?

Get the pipework pressure tested and witness the test.

Ensure there is no lead pipework; I've seen lead joints inflated like a balloon by mains pressure after conversion.

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