Advice & opinions on unvented Vs thermal store

30 Jan 2013
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United Kingdom
Sorry if this is a common thread elsewhere, but I need to make a quick decision.

British Gas just quoted me £6100 to replace my Potterton Suprima and BoilerMate 2 (thermal store) with a similar system.

Once I'd stopped laughing, I called a local heating engineer who seems to have a good reputation in the area.

His quote is far more acceptable, but he wants to replace the thermal store with an unvented system.

Although my aging BoilerMate 2 has been a pain recently, I do appreciate the merits of the Thermal Store system and always thought that I would get a more modern equivalent of it to replace mine.

However, now I am unsure which is the best system for me.

Mains pressure hot water is important to me but I gather both systems do this.

I believe that modern Thermal Stores no longer feed the radiators so the advantages of pre-heated hot water for heating is no longer in the equation.

The thermal store will install easier as all existing pipe work is there. The unvented system will need my bathroom floor taken up to fit some sort of overflow pipe to the outside world as the cylinder cupboard is central in the house and not near and outside wall (bummer!)

My Boilermate 2 has always supplied hot water to two bathrooms very adequately. Hopefully a 225 litre unvented cylinder will also do the same?

The Boilermate could also be a pain at night as it would sometimes call for heat once or twice and the pumps can be a bit noisy at 3AM. Surely an unvented system could be on a timer that heats up early in the morning without making loads of noise?

One final thing, the suggested replacement boiler is made by Ideal. Hopefully this isn't a brand that should be avoided in anyway.

Any advice would be appreciated.
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I've been away for a while, but I can't believe your still here under yet again another name :rolleyes:

I now find it laughable!!
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Thanks. I checked out the xcel heatbank. It does look interesting but also maybe it's a little expensive.

If I went for unvented, is there much annual maintenance? Surely unvented has a longer life overall. My 14 year old thermal store is all scaled up and filled with sludge. Would this not happen on an unvented system and it is sealed.
Oh well, I guess I couldn't expect many replies after the idiotic posts from shambolic & bengasman who seem to believe I'm someone else that they know of.

They have most likely deterred others from comment.
if the system is clean and has good inhibitor i would expect no more or less trouble than from unvented, limescale will damage the safety valves just as quickly as anything else.

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