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Reynoplumb · Joined: 05 Jan 2008 Posts: 21 Location: Devon

Can someone tell me how direct comination tanks work and why we have them? I've never come accross them before.
I've looked at them in the local mechants and understand you have to fit a float valve and warning pipe to the top chamber. I only need one hot water draw off so I assume I can blank the other three off.
The tank is to provide hot water to a portacabin toilets and 3 washbasins at a bottling plant on a farm. The chap alreday has a combi tank in his current set up but is expanding to move into a bigger barn.
Any experience and knowledge on this matter would be much appreciated.
Cheers

thescruff · Moderator Joined: 03 May 2003 Posts: 4481 Location: Bath

A direct combination cylinder is the same as any cylinder except it hasn't got a heating coil.

You connect the mains to the small tank and the hopt pipe to the hole in the top of the cylinder, the hole in the bottom is for a drain off.

You may have a secondary return tapping and if so blank it off.

thescruff · Moderator Joined: 03 May 2003 Posts: 4481 Location: Bath

I would have thought you would be better with something like these.

http://www.heatraesadia.com/hs/heatraes.nsf

Reynoplumb · Joined: 05 Jan 2008 Posts: 21 Location: Devon

If I installed a combi tank do i have to provide any sort of vent pipe back into the tank?

thescruff · Moderator Joined: 03 May 2003 Posts: 4481 Location: Bath

No, mains into the top tank and hot out the side of the cylinder.

It will need an overflow the same as any tank

The Sadia in the link is exactly the same but you can hang it on the wall above the the basin height, whereas the combination tank you have to build a stand for it

Reynoplumb · Joined: 05 Jan 2008 Posts: 21 Location: Devon

Many thanks Scruff