I know plenty
of people that have DIYed an unvented
cylinder.

You have to be BBA approved to fit an unvented cylinder.

Not in this country. What is BBA?

Stop trying to be know-it-all. In the UK you need to be BBA approved to
fit a pressurised cylinder.

Same to you. I don't live in the UK, check my eamil address. So not in this
country is a fact!



There is a big difference. A heat bank and thermals store instantly heat
incoming mains water. The stored water is "primary" water and is heated
by
the boiler. It is the same water, generally, as the boiler water and will
have inhibitor in it. A thermals store has an immersed coil and a heat
bank uses a plate heat exchanger with higher flow rates.

Both thermal stores and heat banks can provide the CH from a flow and
return
taken off the bottom of the cylinder. These are called "integrated"
stores. There are also DHW only stores and heat banks.

An unvented cylinder is similar to vented cylinder, except is used high
pressure mains water, while a vented uses low pressure water from a cold
water tank.

It is best you use a vented thermal store http://www.albion-online.co.uk
(see the Mainsflow) or heat bank (see DPS or Range) as these can be DIYed.
Some heat banks don't even need an overflow, so can be fitted in the
centre of the house.

Range and Albion products are available from most plumbers merchants.

Thanks for taking the time to explain that.

Now if I have the boiler downstairs along with the heat bank, and the CH is
taken off the cylinder, which is unvented, I can't have radiators upstairs?

Can the radiators be feed from/through the heat exchanger? Or alternatively
I guess you pressurise the storeage cylinder as for an unvented system?

Chris

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Remove "nospam." from my address to reply directly