Right I've been looking at the sites that you gave me and could see the
difference at a glance, something that the brochure from Telford didn't
(doesn't) show :-)

So in reality; what do you see as the practical day to day advantages of
a thermal store system over a standard mains pressure cylinder?

A heat bank:

- gives higher flow rates.
- operates on low pressure.
- can be DIYed.
- eliminates inefficient boiler cycling, so cheaper to run.
- Fast re-heat
- does not have an air bubble that requires reinstating every year
- does not require an annual service.
- Can provide CH and DHW from the same cylinder
- Can be packaged all in one unit (you just connect up pipes to the boiler
and rads, with no design work involved)
- Hot water temp at the taps user selectable
- A heat bank does not scale up.
- Can have electric backup for CH and DHW when using an integrated heat
bank or thermal store.

What are the relative costs, in materials only?

A DHW only heat bank/thermal store is less than an unvented cylinder.

Very interesting. I'm going to have to do more research on this. Sounds too
good to be true. What are the disadvantages.?

Chris

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