Hi, does anybody know how to wire a combie, using the combie heating side to
do the heating and a tank of hot water, and the instant (mains water) side
to do just the kitchen tap.

It is a Potterton Performa 28 and using a Siemens heating pack (3 port,
timing clock RWB9, room stat & cylinder stat)

Have got the heating side up and running and doing the water tank, but not
done the mains tap.

Have got the L,N,E coming from the wiring block going to the boiler but they
are only live when the timer tells it to be. I assume there has to be
constant live for the hot tap to be able to fire up at any time.

Any help appreciated

In an earlier contribution to this discussion,
simon beer wrote:

Hi, does anybody know how to wire a combie, using the combie heating
side to do the heating and a tank of hot water, and the instant
(mains water) side to do just the kitchen tap.

It is a Potterton Performa 28 and using a Siemens heating pack (3
port, timing clock RWB9, room stat & cylinder stat)

Have got the heating side up and running and doing the water tank,
but not done the mains tap.

Have got the L,N,E coming from the wiring block going to the boiler
but they are only live when the timer tells it to be. I assume there
has to be constant live for the hot tap to be able to fire up at any
time.

Any help appreciated


The heating side of your boiler is, in effect, powering a Y-plan system - so
the wiring for that side will need to be more or less like Y-plan in
http://content.honeywell.com/uk/homes/systems.htm
[The pump may be different and is probably integral with - and controlled
by - the boiler, so you can probably ignore this bit].

As I understand it, combis mormally have a permanent live and switched live
connection. You will need to connect the permanent live to your mains
supply - i.e. from the fused spur or whatever which powers the whole heating
system. The live boiler connection in the Y-plan diagram needs to be
connected to the boiler's switched live terminal.

--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is Black Hole!

Set Square wrote:
In an earlier contribution to this discussion,
simon beer wrote:

Hi, does anybody know how to wire a combie, using the combie heating
side to do the heating and a tank of hot water, and the instant
(mains water) side to do just the kitchen tap.

It is a Potterton Performa 28 and using a Siemens heating pack (3
port, timing clock RWB9, room stat & cylinder stat)

Have got the heating side up and running and doing the water tank,
but not done the mains tap.

Have got the L,N,E coming from the wiring block going to the boiler
but they are only live when the timer tells it to be. I assume there
has to be constant live for the hot tap to be able to fire up at any
time.

Any help appreciated


The heating side of your boiler is, in effect, powering a Y-plan
system - so the wiring for that side will need to be more or less
like Y-plan in http://content.honeywell.com/uk/homes/systems.htm
[The pump may be different and is probably integral with - and
controlled by - the boiler, so you can probably ignore this bit].

As I understand it, combis mormally have a permanent live and
switched live connection. You will need to connect the permanent live
to your mains supply - i.e. from the fused spur or whatever which
powers the whole heating system. The live boiler connection in the
Y-plan diagram needs to be connected to the boiler's switched live
terminal.

However, many newer combis require a volt free contact pair which you don't
get with a Y-Plan with 3-way valve but do with S-plan with 2-port zone
valves.
If this applies to your boiler then a mains coil relay is required.

On Wed, 10 Dec 2003 18:34:19 +0000, BillR wrote:

Set Square wrote:
In an earlier contribution to this discussion,
simon beer wrote:

Hi, does anybody know how to wire a combie, using the combie heating
side to do the heating and a tank of hot water, and the instant
(mains water) side to do just the kitchen tap.

It is a Potterton Performa 28 and using a Siemens heating pack (3
port, timing clock RWB9, room stat & cylinder stat)

Have got the heating side up and running and doing the water tank,
but not done the mains tap.

Have got the L,N,E coming from the wiring block going to the boiler
but they are only live when the timer tells it to be. I assume there
has to be constant live for the hot tap to be able to fire up at any
time.

Any help appreciated


The heating side of your boiler is, in effect, powering a Y-plan
system - so the wiring for that side will need to be more or less
like Y-plan in http://content.honeywell.com/uk/homes/systems.htm
[The pump may be different and is probably integral with - and
controlled by - the boiler, so you can probably ignore this bit].

As I understand it, combis mormally have a permanent live and
switched live connection. You will need to connect the permanent live
to your mains supply - i.e. from the fused spur or whatever which
powers the whole heating system. The live boiler connection in the
Y-plan diagram needs to be connected to the boiler's switched live
terminal.

However, many newer combis require a volt free contact pair which you don't
get with a Y-Plan with 3-way valve but do with S-plan with 2-port zone
valves.
If this applies to your boiler then a mains coil relay is required.

All boilers (except for one) I know of either require a connection to the mains to demand heat or
they require that you connect to terminals together (sometimes a low
voltage pair - hence the term 'volt free') .

I strongly recommend that you opt for S-plan (see main FAQ). This is much
less troublesome, easier to work around when there is a fault, simpler to
wire and possible to extend later on.

I have installed several combis as hybrid systems they work well (why
wouldn't they) used in this manner.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html

In an earlier contribution to this discussion,
Ed Sirett wrote:


I strongly recommend that you opt for S-plan (see main FAQ). This is
much
less troublesome, easier to work around when there is a fault,
simpler to
wire and possible to extend later on.


The problem is - that according to the initial post - he seems to have
already obtained and installed the bits relating to a Y-plan system. I
assume that if the boiler requires volt-free contacts, he'll have to use the
boiler demand from the 3-port valve to drive a relay.
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is Black Hole!

Set Square wrote:
In an earlier contribution to this discussion,
Ed Sirett wrote:


I strongly recommend that you opt for S-plan (see main FAQ). This is
much
less troublesome, easier to work around when there is a fault,
simpler to wire and possible to extend later on.

I'd wholeheartedly second that. I had a Y plan for 15 years and eventually
got so fed up with it I changed it to S plan.

The problem is - that according to the initial post - he seems to have
already obtained and installed the bits relating to a Y-plan system. I
assume that if the boiler requires volt-free contacts, he'll have to
use the boiler demand from the 3-port valve to drive a relay.

Thats exactly what Ariston tech support told me when I enquired about
putting their combi on an existing Y plan system.
They even had a go at creating a circuit diagram which they sent to me.