On Wed, 1 Sep 2004 17:58:59 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Wed, 1 Sep 2004 15:47:49 +0100, "IMM" wrote:


"Andy Hall" wrote in message

Also making the primary pressurised
with a direct heatbank (i.e. the
bulk contents of the cylinder are pressurised)
means that for Building
Regulations section G purposes it counts as a
sealed storage system and must therefore be
installed by a certified installer.

These are available, but rare and termed directly pressurised.

I wanted to make the point because there are direct heatbanks on the
market and it is not always immediately obvious that they are not
suitable for pressurised primary operation.

They are suitable.

From the DPS site:

"GX units are only suitable for a vented boiler / heating systems with
a Feed & Expansion Tank."

You were on about the whole cylinder and primary circuit being pressurised.

Exactly, and this one is not suitable for that.

On the heat input side there are the following options

1) Heat bank with no coil, run directly using boiler primary water,
vented with integrated or loft F&E tank. Can be DIY.

2) Heat bank with no coil, run directly using boiler primary water,
unvented and pressurised to normal 3bar primary pressure. Needs
professional installation and heatbank cylinder able to take the
pressure.

3) Heat bank with plate heat exchanger on primary side and pump. Bulk
(tertiary) water in heatbank is vented (probably with integrated FE
tank) and separate pressurised (or vented) boiler primary. DIY install
with building notice.

4) As 3 but with coil on input side of heatbank with boiler primary
water (sealed or open vented) going through it (indirect). Not as
efficient as 3 but still a DIY job and doesn't need additional pump.


Having the primary vented, whether with an integral F&E tank or not
means that this can be a DIY job, although is still subject to a
Building Notice because of part L1.

However, some boilers will not accept
having an open vented primary,

Few and far between.

I've got one.

You have not got a heat bank.

That's not the point.

You have NOT Got a heat bank.!

That's irrelevant. You haven't got a hundred acres.



There are boilers around that are designed for
sealed system use. Vaillant ecoMAX is one example in addition to the
Micromat that I have,Viessmann is another.


You are confused.

I'm seldom confused and certainly not here.


..andy

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