Extra insulation for unvented hot water cylinder?

[Mark]

I've got a electric direct unvented cylinder, which is factory insulated.

Thing is, the storage cupboard that it's in still gets very hot. All the pipes are insulated with foam (13 mm).

As there is signficant heat escaping into the storage room - I was hoping that this could be kept in the water and hopefully reduce bills.

Am I likely to get any significant benefit by sticking a jacket over the cylinder (with suitable holes for all the pipes and heaters) - or will this simply be a waste of time and effort? Or indeed, would such additional insulation cause problems in some way?

[Doctor Drivel]

If loft above, then fit extra insulation over the cupboard, then add draught excluders to the door. The heat then should just stay to a large extent.

[Set Square]

I don't think that extra insulation would cause problems as such - but you'd need a lot of it to make much difference. Is it in an airing cupboard which benefits from being warm? If so, why not insulate the walls of the cupboard to stop the heat escaping any further (which will reduce the amount coming out of the cylinder to replace it) and have a nice warm airing cupboard?

[Lobster]

I have an unvented cylinder, also in a warm airing cupboard. Have you actually felt the outside of the tank? Mine feels no more than room temp to the touch, even when fully heated up, from which I conclude it's already pretty well insulated and the heat in the cupboard isn't derived from the tank directly.

David

[Christian McArdle]

You will probably get some benefit, although it won't be massive on a modern insulated cylinder to Part L. You might want to thicken up the pipe insulation and tape it up, so there are no holes for draughts between sections of insulation.

Christian.