[Greenbuilding] holding tank for solar hot water

[Bruno M.]

Hi Tom,


Is this for culturing algae and bacteria or for human consumption/use?   ;-)

Maybe better use in your construction a PVC or better a PE-foil or EPDM liner.
( to not expose the foam to the water directly, which in your proposal will 
get penetrated by the water anyway)

And if this tank has no pressure how you gonna get the hot water to your 
point(s) of use?

Drainback is very foolproof, good idea.

grts
Bruno M.
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At 22:00 04/02/2007, Tom wrote:
>  hi,
>i'm planning a holding tank for solar hot water - temps up to 180F, no 
>pressure. does anyone see a problem with lining a concrete box with closed 
>cell foam board exposed to the water?
>by the way, this is planned as a drainback system, which i think is a more 
>elegant solution to the freezing issue, if done right..
>
>thanks,
>tom
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