In an earlier contribution to this discussion,
wrote:

On 2 Oct, 11:58, "Roger Mills" wrote:
In an earlier contribution to this discussion,


What you've got (or had?) is a fairly conventional S-Plan fully
pumped system - except that it seems to be arse about face!

Let's assume for a moment that we turn the pump round, so that the
flow is upwards. Pipe 2 is then the combined HW + CH flow pipe from
the boiler. After going through the pump, the water splits into 2
circuits. The HW circuit goes through the HW valve to the coil in
the cylinder, out again and back down pipe 3 to the boiler. The CH
circuit goes through the CH valve and then along pipe 1 to the
radiators - and the radiator returns presumably combine somewhere
and then connect into pipe 3 to go back to the boiler.

With the flow through the pump going downwards, everthing works
exactly the same - except that circulation is in the opposite
direction, with flows and returns being interchanged. That may have
been done deliberately, to prevent the F&E tank from pumping over.
Conventionally (with the pump going in the normal direction), the
connections to the F&E tank should be in the main flow pipe (2) just
before the pump.

I haven't a clue what the 15mm pipe is which appears to by-pass the
pump!

The pipe labelled 'domestic HW feed?' is the cold feed into the DHW
tank from the large header tank in the attic. When you open a hot
tap, cold water flows into the bottom of the cylinder expelling hot
water out of the top connection (labelled 'domestic HW out?') and on
to the taps.

What you had - albeit somewhat unconventional - should have worked.
Why did you change it?
--
Cheers,
Roger


sorry Roger, I've also just noticed that I keep replying to you alone
and not to the group. many apologies....

Try to make sure that you copy them to the group, for all to see - some have
been already. [I hadn't actually seen the private replies 'cos - like it
says in my signature - I don't monitor the googlemail address very often!]
--
Cheers,
Roger
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