Hello,

We have a wiki page he -

http://wiki.diyfaq.org.uk/index.php?...s_and_Zonin g

with details of the different arrangements for domestic central heating.
I had prepared wiring diagrams for the site and also for download as a
pdf: -

http://www.diyfaq.org.uk/docs/Sundial-Plans-Rev1c.pdf
http://www.diyfaq.org.uk/docs/Sundial-Wiring-Rev1c.pdf

Unfortunately, I made a transcription error in the wiring diagram for
Y-plan which is not obvious and which would cause incorrect operation of
the system if implemented. Fortunately, someone spotted the error and
posted a note on the wiki.

I have now corrected the error in the Y-plan wiring diagram. If you have
previously downloaded the image of the Y-plan wiring diagram or the
pdf's (at Rev 1b), then you should discard them and re-download the
revised items (at Rev 1c). Please pass on to anybody you you may have
emailed the pdf's to.

Thanks to whoever spotted the mistake and to Mr Rumm for updating the
the wiki.


Cheers,
Dave Osborne

In an earlier contribution to this discussion,
Dave Osborne wrote:

Hello,

We have a wiki page he -

http://wiki.diyfaq.org.uk/index.php?...s_and_Zonin g

with details of the different arrangements for domestic central
heating. I had prepared wiring diagrams for the site and also for
download as a pdf: -

http://www.diyfaq.org.uk/docs/Sundial-Plans-Rev1c.pdf
http://www.diyfaq.org.uk/docs/Sundial-Wiring-Rev1c.pdf

Unfortunately, I made a transcription error in the wiring diagram for
Y-plan which is not obvious and which would cause incorrect operation
of the system if implemented. Fortunately, someone spotted the error
and posted a note on the wiki.

I have now corrected the error in the Y-plan wiring diagram. If you
have previously downloaded the image of the Y-plan wiring diagram or
the pdf's (at Rev 1b), then you should discard them and re-download
the revised items (at Rev 1c). Please pass on to anybody you you may
have emailed the pdf's to.

Thanks to whoever spotted the mistake and to Mr Rumm for updating the
the wiki.


Cheers,
Dave Osborne


Excellent!

I wonder whether it's worth adding one additional refinement to reflect the
way in which many systems are *actually* configured? I'm referring here to
pump over-run arrangements. Your diagrams faithfully reproduce the original
Honeywell 'plan' details - with the boiler and pump wired in parallel in all
cases. However, many (most?) modern systems ain't wired like that, but are
wired as follows:

The boiler has several additional terminals - permanent live, plus N, E, L
for pump connection, and the terminal shown as L on the diagrams becomes a
"switched live" (demand) to distinguish it from permanent live. The pump is
then, of course, connected to the boiler's pump terminals rather than as in
the diagrams.

[This enables the boiler to control the pump, and to keep it running after
the demand has been removed in order to carry away the residual heat].

I would suggest that if you take up this idea, the modified diagrams should
be in addition to the original ones rather than replacing them so that, for
example, we might have Basic Y-Plan *and* Y-Plan with pump over-run, etc.
The schematic for S-Plan (and S+) with pump over-run would also need to
include a by-pass circuit.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

"Dave Osborne" wrote in message
...
Hello,

We have a wiki page he -

http://wiki.diyfaq.org.uk/index.php?...s_and_Zonin g

with details of the different arrangements for domestic central heating. I
had prepared wiring diagrams for the site and also for download as a
pdf: -

http://www.diyfaq.org.uk/docs/Sundial-Plans-Rev1c.pdf
http://www.diyfaq.org.uk/docs/Sundial-Wiring-Rev1c.pdf

Unfortunately, I made a transcription error in the wiring diagram for
Y-plan which is not obvious and which would cause incorrect operation of
the system if implemented. Fortunately, someone spotted the error and
posted a note on the wiki.

I have now corrected the error in the Y-plan wiring diagram. If you have
previously downloaded the image of the Y-plan wiring diagram or the pdf's
(at Rev 1b), then you should discard them and re-download the revised
items (at Rev 1c). Please pass on to anybody you you may have emailed the
pdf's to.

Thanks to whoever spotted the mistake and to Mr Rumm for updating the the
wiki.


Cheers,
Dave Osborne

Just after printing rev 1b out for laminating as well:-(

An excellent effort despite the earlier small mistake that I missed despite
wiring up quite a few Y plans. Far better than any other diagrams I have
seen

I love the extra page with the internals of the mid position valve

Well done and thank you

Adam

Roger Mills wrote:



Excellent!

I wonder whether it's worth adding one additional refinement to reflect the
way in which many systems are *actually* configured? I'm referring here to
pump over-run arrangements. Your diagrams faithfully reproduce the original
Honeywell 'plan' details - with the boiler and pump wired in parallel in all
cases. However, many (most?) modern systems ain't wired like that, but are
wired as follows:

The boiler has several additional terminals - permanent live, plus N, E, L
for pump connection, and the terminal shown as L on the diagrams becomes a
"switched live" (demand) to distinguish it from permanent live. The pump is
then, of course, connected to the boiler's pump terminals rather than as in
the diagrams.

[This enables the boiler to control the pump, and to keep it running after
the demand has been removed in order to carry away the residual heat].

I would suggest that if you take up this idea, the modified diagrams should
be in addition to the original ones rather than replacing them so that, for
example, we might have Basic Y-Plan *and* Y-Plan with pump over-run, etc.
The schematic for S-Plan (and S+) with pump over-run would also need to
include a by-pass circuit.

Well, I'd be willing to bet that there are many millions of systems out
there wired to a classic Sundial plan. Mine is, for one... :-)

However, I'm quite happy to do additional drawings for more modern
installation arrangements.


From my limited reading, the following ideas come to mind:-

1. Wiring diagram for S-plus with one and two extra heating zones.

2. Conventional (i.e. not system) boiler with pump-overrun timer (as you
have suggested above).

3. Classic Y-plan, S-plan with retro-fitted separate pump overrun timer.
(e.g. Broyce Controls M1EDF RS 296-7393).

4. System boiler? I'm kind of assuming that these come with wiring
diagrams and have "wiring centres" built in, so the programmer (if
external) and the thermostats connect directly to the boiler.

5. Versions of Y, S and S-plus where there is no central timer, just
programmable thermostats. Is this even a valid way of wiring a system?


I would need someone or three to commit to assisting with providing
suitable source material (including sketches) and/or reviewing and
commenting on draft drawings as I am no expert on central heating controls.

Any takers?

DaveyOz

ARWadsworth wrote:

"Dave Osborne" wrote in message
...
Hello,

We have a wiki page he -

http://wiki.diyfaq.org.uk/index.php?...s_and_Zonin g


with details of the different arrangements for domestic central
heating. I had prepared wiring diagrams for the site and also for
download as a pdf: -

http://www.diyfaq.org.uk/docs/Sundial-Plans-Rev1c.pdf
http://www.diyfaq.org.uk/docs/Sundial-Wiring-Rev1c.pdf

Unfortunately, I made a transcription error in the wiring diagram for
Y-plan which is not obvious and which would cause incorrect operation
of the system if implemented. Fortunately, someone spotted the error
and posted a note on the wiki.

I have now corrected the error in the Y-plan wiring diagram. If you
have previously downloaded the image of the Y-plan wiring diagram or
the pdf's (at Rev 1b), then you should discard them and re-download
the revised items (at Rev 1c). Please pass on to anybody you you may
have emailed the pdf's to.

Thanks to whoever spotted the mistake and to Mr Rumm for updating the
the wiki.


Cheers,
Dave Osborne

Just after printing rev 1b out for laminating as well:-(

An excellent effort despite the earlier small mistake that I missed
despite wiring up quite a few Y plans. Far better than any other
diagrams I have seen

I love the extra page with the internals of the mid position valve

Well done and thank you

Adam

Thanks Adam. Please see my reply to Roger also.

"Dave Osborne" wrote in message
...
Roger Mills wrote:



Excellent!

I wonder whether it's worth adding one additional refinement to reflect
the way in which many systems are *actually* configured? I'm referring
here to pump over-run arrangements. Your diagrams faithfully reproduce
the original Honeywell 'plan' details - with the boiler and pump wired in
parallel in all cases. However, many (most?) modern systems ain't wired
like that, but are wired as follows:

The boiler has several additional terminals - permanent live, plus N, E,
L for pump connection, and the terminal shown as L on the diagrams
becomes a "switched live" (demand) to distinguish it from permanent live.
The pump is then, of course, connected to the boiler's pump terminals
rather than as in the diagrams.

[This enables the boiler to control the pump, and to keep it running
after the demand has been removed in order to carry away the residual
heat].

I would suggest that if you take up this idea, the modified diagrams
should be in addition to the original ones rather than replacing them so
that, for example, we might have Basic Y-Plan *and* Y-Plan with pump
over-run, etc. The schematic for S-Plan (and S+) with pump over-run would
also need to include a by-pass circuit.

Well, I'd be willing to bet that there are many millions of systems out
there wired to a classic Sundial plan. Mine is, for one... :-)

However, I'm quite happy to do additional drawings for more modern
installation arrangements.


From my limited reading, the following ideas come to mind:-

1. Wiring diagram for S-plus with one and two extra heating zones.

That would be good. Zoning of CH is becoming more common. Possible problems
would be the way the CH zones are controlled. Some installers use three
channel programmers (or extra programmers) and others just use extra room
stats that are controlled by just one programmer.

2. Conventional (i.e. not system) boiler with pump-overrun timer (as you
have suggested above).

Probably the most common set up now on a new regular boiler. Yes that would
be a good one to go for.

3. Classic Y-plan, S-plan with retro-fitted separate pump overrun timer.
(e.g. Broyce Controls M1EDF RS 296-7393).

Not sure about this one. I have added pump over runs but only because a lack
of available cables down to the old boiler and the customer did not want
kitchen tiles smashing off the wall etc.


4. System boiler? I'm kind of assuming that these come with wiring
diagrams and have "wiring centres" built in, so the programmer (if
external) and the thermostats connect directly to the boiler.

Maybe. But a system boiler usually only needs Permant Live, Neutral, Earth
and a Call Live. The pump is taken care of internally by the boiler PCB

5. Versions of Y, S and S-plus where there is no central timer, just
programmable thermostats. Is this even a valid way of wiring a system?

It is a valid way of wiring a boiler. Unless someone comes up with a genius
"all in one" diagram then I suspect that there would be too many variables
to make this a viable option. The system could consist of a mixture of
remote and hard wired thermostats and it is not possible to cover all
aspects.

I would need someone or three to commit to assisting with providing
suitable source material (including sketches) and/or reviewing and
commenting on draft drawings as I am no expert on central heating
controls.

Any takers?


If you do not mind hand drawn scanned sketches then no problem.

Adam

ARWadsworth wrote:


Any takers?


If you do not mind hand drawn scanned sketches then no problem.

Adam

Ok, please feel free to amend existing drawings/wiring diagrams by hand
or draw new sketches or whatever is best for you and email them to me.

Cheers,
DaveyOz

In an earlier contribution to this discussion,
Dave Osborne wrote:


Well, I'd be willing to bet that there are many millions of systems
out there wired to a classic Sundial plan. Mine is, for one... :-)

However, I'm quite happy to do additional drawings for more modern
installation arrangements.


From my limited reading, the following ideas come to mind:-

1. Wiring diagram for S-plus with one and two extra heating zones.

Yes - good idea.


2. Conventional (i.e. not system) boiler with pump-overrun timer (as
you have suggested above).

Yes - although it's not necessarily a *timer* per se. My boiler simply keeps
the pump running until the output temperature falls below the boiler stat
setting. The important thing is that the pump is controlled by the boiler -
using whatever internal logic it sees fit - rather than being connected in
parallel with the boiler demand.

3. Classic Y-plan, S-plan with retro-fitted separate pump overrun
timer. (e.g. Broyce Controls M1EDF RS 296-7393).

Maybe(?) but I don't know how common this is. My impression is that if the
boiler *needs* the pump to over-run, it will provide the logic and the
connections.

4. System boiler? I'm kind of assuming that these come with wiring
diagrams and have "wiring centres" built in, so the programmer (if
external) and the thermostats connect directly to the boiler.

I've not got any experience of these, I'm afraid - but I assume they're
simple to wire 'cos most of it will have been done for you.

5. Versions of Y, S and S-plus where there is no central timer, just
programmable thermostats. Is this even a valid way of wiring a system?


Unusual I would have thought - because you would normally have a timer of
some sort (rather than a programmable stat) for the HW. You could, of
course, just have a single channel timer for the HW and connect the
programmable room stat(s) directly to the FCU. That would certainly be
valid.

I would need someone or three to commit to assisting with providing
suitable source material (including sketches) and/or reviewing and
commenting on draft drawings as I am no expert on central heating
controls.
Any takers?

DaveyOz

I'm more than willing to review and comment. I'm also happy to have a go at
amending the existing diagrams - preferably electronically - but that
assumes that I have the same tools as those with which you created the
diagrams, which may or may not be the case. What *did* you use?

Failing that, I could probably print them, mark them up by hand and then
scan them.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

Roger Mills wrote:
In an earlier contribution to this discussion,
Dave Osborne wrote:

Well, I'd be willing to bet that there are many millions of systems
out there wired to a classic Sundial plan. Mine is, for one... :-)

However, I'm quite happy to do additional drawings for more modern
installation arrangements.


From my limited reading, the following ideas come to mind:-

1. Wiring diagram for S-plus with one and two extra heating zones.

Yes - good idea.



2. Conventional (i.e. not system) boiler with pump-overrun timer (as
you have suggested above).

Yes - although it's not necessarily a *timer* per se. My boiler simply keeps
the pump running until the output temperature falls below the boiler stat
setting. The important thing is that the pump is controlled by the boiler -
using whatever internal logic it sees fit - rather than being connected in
parallel with the boiler demand.

Understood. "Pump Overrun Facility" from mow on!


3. Classic Y-plan, S-plan with retro-fitted separate pump overrun
timer. (e.g. Broyce Controls M1EDF RS 296-7393).

Maybe(?) but I don't know how common this is. My impression is that if the
boiler *needs* the pump to over-run, it will provide the logic and the
connections.

4. System boiler? I'm kind of assuming that these come with wiring
diagrams and have "wiring centres" built in, so the programmer (if
external) and the thermostats connect directly to the boiler.

I've not got any experience of these, I'm afraid - but I assume they're
simple to wire 'cos most of it will have been done for you.

5. Versions of Y, S and S-plus where there is no central timer, just
programmable thermostats. Is this even a valid way of wiring a system?


Unusual I would have thought - because you would normally have a timer of
some sort (rather than a programmable stat) for the HW.

Good point.

You could, of
course, just have a single channel timer for the HW and connect the
programmable room stat(s) directly to the FCU. That would certainly be
valid.

OK, I might draw this as an example of an S-plus system.

I would need someone or three to commit to assisting with providing
suitable source material (including sketches) and/or reviewing and
commenting on draft drawings as I am no expert on central heating
controls.
Any takers?

DaveyOz

I'm more than willing to review and comment. I'm also happy to have a go at
amending the existing diagrams - preferably electronically - but that
assumes that I have the same tools as those with which you created the
diagrams, which may or may not be the case. What *did* you use?

Well back in August I started in AutoCad cos I'm used to doing drawings
in Autocad, but then I decided to use Adobe Illustrator to tart them up
and make gifs. However, I ended up largely redoing them in Illustrator
and have now dropped AutoCad as an intermediate.


Failing that, I could probably print them, mark them up by hand and then
scan them.

No problem. Whatever works for you.

Roger Mills wrote:


I wonder whether it's worth adding one additional refinement to reflect the
way in which many systems are *actually* configured? I'm referring here to
pump over-run arrangements. Your diagrams faithfully reproduce the original
Honeywell 'plan' details - with the boiler and pump wired in parallel in all
cases.

Not true, see C-plan. In this arrangement, the boiler and pump are not
wired in parallel. The boiler can run without the pump when there is
call for hot water but no call for heating.

However, my understanding is that this type of system (C-plan) is
deprecated and if you were to replace the boiler, then you would
automatically upgrade to fully-pumped and then you would need to change
wiring to S-plan and probably implement the boiler overrun as discussed.

In message , Roger Mills
writes
In an earlier contribution to this discussion,
Dave Osborne wrote:


Well, I'd be willing to bet that there are many millions of systems
out there wired to a classic Sundial plan. Mine is, for one... :-)

However, I'm quite happy to do additional drawings for more modern
installation arrangements.


From my limited reading, the following ideas come to mind:-

1. Wiring diagram for S-plus with one and two extra heating zones.

Yes - good idea.


2. Conventional (i.e. not system) boiler with pump-overrun timer (as
you have suggested above).

Yes - although it's not necessarily a *timer* per se. My boiler simply keeps
the pump running until the output temperature falls below the boiler stat
setting.

What boiler is that ?


--
geoff

In an earlier contribution to this discussion,
Dave Osborne wrote:

Roger Mills wrote:


I wonder whether it's worth adding one additional refinement to
reflect the way in which many systems are *actually* configured? I'm
referring here to pump over-run arrangements. Your diagrams
faithfully reproduce the original Honeywell 'plan' details - with
the boiler and pump wired in parallel in all cases.

Not true, see C-plan. In this arrangement, the boiler and pump are not
wired in parallel. The boiler can run without the pump when there is
call for hot water but no call for heating.

Sorry - you're right - it's not *quite* all cases - I overlooked C-Plan
systems!

However, my understanding is that this type of system (C-plan) is
deprecated and if you were to replace the boiler, then you would
automatically upgrade to fully-pumped and then you would need to
change wiring to S-plan and probably implement the boiler overrun as
discussed.

True - but there is still scope for converting a 'conventional' gravity
HW/pumped CH system to C-Plan *without* changing the boiler, in order to
gain the advantages of HW temperature control and boiler interlock. However,
these systems invariably use boilers which *don't* need pump over-run -
almost by definition, because the pump doesn't run in HW-only mode, anyway.
So, in the case of C-Plan, the existing Honeywell info will suffice without
requiring any embellishments.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

In an earlier contribution to this discussion,
geoff wrote:

In message , Roger Mills
writes
In an earlier contribution to this discussion,
Dave Osborne wrote:


Well, I'd be willing to bet that there are many millions of systems
out there wired to a classic Sundial plan. Mine is, for one... :-)

However, I'm quite happy to do additional drawings for more modern
installation arrangements.


From my limited reading, the following ideas come to mind:-

1. Wiring diagram for S-plus with one and two extra heating zones.

Yes - good idea.


2. Conventional (i.e. not system) boiler with pump-overrun timer (as
you have suggested above).

Yes - although it's not necessarily a *timer* per se. My boiler
simply keeps the pump running until the output temperature falls
below the boiler stat setting.

What boiler is that ?

It's a Mk I Baxi Solo powered flue jobby - c1990 vintage.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

In an earlier contribution to this discussion,
Dave Osborne wrote:

Roger Mills wrote:

I'm more than willing to review and comment. I'm also happy to have
a go at amending the existing diagrams - preferably electronically -
but that assumes that I have the same tools as those with which you
created the diagrams, which may or may not be the case. What *did*
you use?

Well back in August I started in AutoCad cos I'm used to doing
drawings in Autocad, but then I decided to use Adobe Illustrator to
tart them up and make gifs. However, I ended up largely redoing them
in Illustrator and have now dropped AutoCad as an intermediate.

I haven't got *any* of them!

Failing that, I could probably print them, mark them up by hand and
then scan them.

No problem. Whatever works for you.

Looks like it will have to be knife and fork methods then! Is the email
address in your header genuine if I remove the obvious spam-trap?
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

Roger Mills wrote:


Looks like it will have to be knife and fork methods then! Is the email
address in your header genuine if I remove the obvious spam-trap?

Yes, in fact you Adam & John Rumm should have received an email from me.
Let me know if your email addresses are not valid.

In message , Roger Mills
writes
In an earlier contribution to this discussion,
geoff wrote:

In message , Roger Mills
writes
In an earlier contribution to this discussion,
Dave Osborne wrote:


Well, I'd be willing to bet that there are many millions of systems
out there wired to a classic Sundial plan. Mine is, for one... :-)

However, I'm quite happy to do additional drawings for more modern
installation arrangements.


From my limited reading, the following ideas come to mind:-

1. Wiring diagram for S-plus with one and two extra heating zones.

Yes - good idea.


2. Conventional (i.e. not system) boiler with pump-overrun timer (as
you have suggested above).

Yes - although it's not necessarily a *timer* per se. My boiler
simply keeps the pump running until the output temperature falls
below the boiler stat setting.

What boiler is that ?

It's a Mk I Baxi Solo powered flue jobby - c1990 vintage.

Ah - simply switched from the stat then, the solo2 the pump overrun
would be time, not temp controlled


--
geoff

In an earlier contribution to this discussion,
geoff wrote:

In message , Roger Mills
writes
In an earlier contribution to this discussion,
geoff wrote:

In message , Roger Mills
writes
In an earlier contribution to this discussion,
Dave Osborne wrote:


Well, I'd be willing to bet that there are many millions of
systems out there wired to a classic Sundial plan. Mine is, for
one... :-) However, I'm quite happy to do additional drawings for more
modern
installation arrangements.


From my limited reading, the following ideas come to mind:-

1. Wiring diagram for S-plus with one and two extra heating zones.

Yes - good idea.


2. Conventional (i.e. not system) boiler with pump-overrun timer
(as you have suggested above).

Yes - although it's not necessarily a *timer* per se. My boiler
simply keeps the pump running until the output temperature falls
below the boiler stat setting.

What boiler is that ?

It's a Mk I Baxi Solo powered flue jobby - c1990 vintage.

Ah - simply switched from the stat then, the solo2 the pump overrun
would be time, not temp controlled

Yes, that's right. There's an extra set of change-over contacts on the
boiler stat which connects the pump either to boiler demand or to permanent
live depending on whether the boiler is below or above the set temperature.

Unfortunately, this doesn't always have the desired effect! There are some
cases where the demand is cut when the stat is just below the set point, so
the pump is immediately cut. The residual heat then sends the temperature
up, and the stat switches so that the pump comes on again - but too late to
prevent the over-heat stat from tripping. So I have re-engineered mine by
using an external timer (intended for bathroom fans) which keeps the pump
running for about 4 minutes after the boiler has switched it off - thus
avoiding the above problem.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

In an earlier contribution to this discussion,
Dave Osborne wrote:

Roger Mills wrote:


Looks like it will have to be knife and fork methods then! Is the
email address in your header genuine if I remove the obvious
spam-trap?

Yes, in fact you Adam & John Rumm should have received an email from
me. Let me know if your email addresses are not valid.


Ah yes, so I have! The address is genuine but - like it says in my sig - I
don't look at it very often so I need to be prompted when someone sends an
email to it.

I'll respond when I've had a chance to look at it.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!