alt.energy.homepower

"daestrom" wrote in message
news:46ddbdcc$0$4071$4c368faf@ ...
>
>> Here in the US, most hot water tanks fail gradually, by leaking their
>> contents all over the floor. This generally happend withing a year or
>> two of the tanks warranty expiration. :-)
>
> Yep, been there. Can be extended if you take the time to check the zinc
> anode, but most folks don't even know where to look :-)

In the UK unvented cylinders "tend" to be stainless steel. Look at this all
in one stainless steel boiler and tank-in-tank design - a tank inside a
thermal store:

/
Manual:
/pdf/HeatMaster%
The manual explains the operation very well with nice diagrams too. It
always condenses promoting high efficiency.

Here is a Dutch copper design - still very good.
/ ?section=000200130001

These units do CH and DHW and are "very" efficient.