Is there going to be any problem with this set up?

At the moment theres a basic two channel mechanical timeswitch in the
kitchen and a wired 'stat on the first floor landing. The timer
switches both water and heating on together but manual over-ride
allows them to be operated independently. There are two motorised
valves in the airing cupboard with the boiler.

I want to put a ACL Tempus2 7 day timeswitch in the airing cupboard to
control hot water (i figure with a 7 day timer manual override will be
rare) and use an ACL Wireless Digistat3i to control the heating. IME
a 'stat is far more useful placed in your primary living space (ie the
living room) than a draughty hallway with few rad's.

Are there any pitfalls I haven't thought of? The boiler is a
Keston130. I figure it's going to take a bit of time to work out
what's what in the boiler cupboard but all the new wiring will be in
one place.

AJ

Are there any pitfalls I haven't thought of?

Firstly, use a 2 channel programmer and wire the new programmable stat
through the CH side. There is almost no difference in price. You don't use
the programmer for actual timing, but it is very useful as a central
location to turn everything off and on without having to traipse round to
the room stat. The CH side is usually set to 24H (or Off). It is
particularly useful if you have multiple heating zones, or your room stat
doesn't have a simple "Off" feature, as many don't.

Secondly, ensure that you have a cylinder thermostat. It sounds like you
have an S plan system. If no cylinder stat is present, you need to insert it
in series between the programmer "HW On" output and the hot water zone valve
motor live (normally brown) wire.

Christian.

On Wed, 14 Jan 2004 10:54:05 -0000, "Christian McArdle"
wrote:

Are there any pitfalls I haven't thought of?

Firstly, use a 2 channel programmer and wire the new programmable stat
through the CH side.

Why use a programmable room stat if there is already a 2 channel
programmer, surely a standard wireless stat will suffice.

There is almost no difference in price. You don't use
the programmer for actual timing, but it is very useful as a central
location to turn everything off and on without having to traipse round to
the room stat.

The spur that turns off the heating could quite easily do that. And it
is unlikely anyone will have to traipse round to find the room stat,
surely it would be where you screwed it on the wall?

The CH side is usually set to 24H (or Off). It is
particularly useful if you have multiple heating zones,

Which there aren't as there are only 2 valves, so that would be an S
plan then.

or your room stat
doesn't have a simple "Off" feature, as many don't.

Secondly, ensure that you have a cylinder thermostat. It sounds like you
have an S plan system. If no cylinder stat is present, you need to insert it
in series between the programmer "HW On" output and the hot water zone valve
motor live (normally brown) wire.




SJW
A.C.S. Ltd.

Why use a programmable room stat if there is already a 2 channel
programmer, surely a standard wireless stat will suffice.

Several reasons. Basically, the advantages of using a programmable stat over
a separate stat and programmer a

1. Controls are in the living area rather than in a manky undersink cupboard
or inaccessible airing cupboard. This enables manual override and
programming to be easily achieved.

2. Rather than turning off completely, the stat can just turn down the
temperature, to say, 12C, ensuring that the house doesn't get freezing
overnight, or whilst you are out.

3. Complex control laws can be used that can predict the house's response to
heat, enabling temperature overshoot to be controlled and enabling the
device to predict how long before the required start period the heating
needs to be on.

The spur that turns off the heating could quite easily do that. And it
is unlikely anyone will have to traipse round to find the room stat,
surely it would be where you screwed it on the wall?

The spur will also turn off the hot water, which may not be desired. If you
are fiddling around with the system whilst testing, you don't want to have
to frequently disappear down the stairs to turn the thermostat on and off
when the nearby programmer can do the same function for pennies more than a
single channel.

Christian.

On Wed, 14 Jan 2004 11:48:20 -0000, "Christian McArdle"
wrote:

Why use a programmable room stat if there is already a 2 channel
programmer, surely a standard wireless stat will suffice.

Several reasons. Basically, the advantages of using a programmable stat over
a separate stat and programmer a

I was actually going more for the two programmers in series, a
programmable roomstat is a good idea in my opinion.

1. Controls are in the living area rather than in a manky undersink cupboard
or inaccessible airing cupboard. This enables manual override and
programming to be easily achieved.

Fair enough, but if it's set up correctly you don't really need to
alter the timing. Although it's all up to the individual.

2. Rather than turning off completely, the stat can just turn down the
temperature, to say, 12C, ensuring that the house doesn't get freezing
overnight, or whilst you are out.

You've lost me there, you can turn the temp up and down regardless of
where the stat and programmer are.

3. Complex control laws can be used that can predict the house's response to
heat, enabling temperature overshoot to be controlled and enabling the
device to predict how long before the required start period the heating
needs to be on.

O.k. then, I'll let you off with that one!

The spur that turns off the heating could quite easily do that. And it
is unlikely anyone will have to traipse round to find the room stat,
surely it would be where you screwed it on the wall?

The spur will also turn off the hot water, which may not be desired. If you
are fiddling around with the system whilst testing, you don't want to have
to frequently disappear down the stairs to turn the thermostat on and off
when the nearby programmer can do the same function for pennies more than a
single channel.

I personally only test my heating systems once and then thats it, it
generally doesn't break down that often.

So in general then to the OP, yes, your way would work but there are
other ways, a good programmable room stat would be my choice coupled
with a single channel on the water, but it's a free country!


SJW
A.C.S. Ltd.

Fair enough, but if it's set up correctly you don't really need to
alter the timing. Although it's all up to the individual.

Unfortunately, when setting the timer in January, you don't know that a
couple of mates are coming over on July 14th until 2am. A handy nearby
"boost" button could be useful here, rather than searching for a torch
because in the low light you can't see the programmer in its cubbyhole and
can't remember which button boosts the heating (and the manufacturer decided
to scratch the legend in rather than using high contrast printing, but you
don't read braille).

2. Rather than turning off completely, the stat can just turn down
the temperature, to say, 12C, ensuring that the house doesn't get
freezing overnight, or whilst you are out.

You've lost me there, you can turn the temp up and down regardless of
where the stat and programmer are.

What I mean is that a programmable room stat doesn't turn off and on, it
just changes temperature. My "off" temperature is 10C. My "on" temperature
is 22C. If you had a separate programmer, the "off" temperature is -273C, as
it just cuts the power totally, with no ability to just keep it ticking
along for the benefit of your furniture and pipework.

So in general then to the OP, yes, your way would work but there are
other ways, a good programmable room stat would be my choice coupled
with a single channel on the water, but it's a free country!

You could always put a switch for the CH side. But then twin channel
programmers are basically the same price as single channel ones, so it would
be cheaper and neater just to use a twin channel programmer. OTOH, it isn't
that important on a single zone heating system. On multiple zones, it is far
more useful.

Christian.

In article ,
Christian McArdle wrote:
Why use a programmable room stat if there is already a 2 channel
programmer, surely a standard wireless stat will suffice.

Several reasons. Basically, the advantages of using a programmable stat
over a separate stat and programmer a

1. Controls are in the living area rather than in a manky undersink
cupboard or inaccessible airing cupboard. This enables manual override
and programming to be easily achieved.

Since this is a DIY group, I'd then suggest moving the programmer to a
correct and accessible position - usually in the kitchen.

I've got an accessible programmer and programmable thermostat. If the
house is empty during the day I switch to 'on twice'. If I'm in, on once.
If it's very cold, on continuously. Much easier than messing with the
programmable thermostat.

--
*Yes, I am an agent of Satan, but my duties are largely ceremonial

Dave Plowman London SW 12
RIP Acorn

I've got an accessible programmer and programmable thermostat. If the
house is empty during the day I switch to 'on twice'. If I'm in, on
once. If it's very cold, on continuously. Much easier than messing
with the programmable thermostat.

It's just that I prefer not to cut the power completely when "off". I don't
want it getting too cold (i.e. below 10C), even when I'm not there. My prog
room stat is on the approximate equivalent of "twice" on weekdays, the
middle of which can be filled in by pressing a single button, if required. I
suppose some stats may have more complicated manual overrides.

Christian.

In an earlier contribution to this discussion,
Christian McArdle wrote:


Unfortunately, when setting the timer in January, you don't know that
a couple of mates are coming over on July 14th until 2am. A handy
nearby "boost" button could be useful here, . . .


Do you know something about the long range weather forecast with regard to a
particularly cold spell in July?! g

Most of us will have our heating switched off then!
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is Black Hole!

Do you know something about the long range weather forecast with
regard to a particularly cold spell in July?! g

Most of us will have our heating switched off then!

D'oh!

Christian.

Christian McArdle wrote:
Do you know something about the long range weather forecast with
regard to a particularly cold spell in July?! g

Most of us will have our heating switched off then!

D'oh!

Alternatively, I thought the OP was in Tasmania...

Christian.

In article ,
Christian McArdle wrote:
It's just that I prefer not to cut the power completely when "off". I
don't want it getting too cold (i.e. below 10C), even when I'm not there.

If your house normally drops from say 20C in the morning to 10C by the
evening, I'd say you desperately need the insulation sorted.

--
*You! Off my planet!

Dave Plowman London SW 12
RIP Acorn

It's just that I prefer not to cut the power completely when "off". I
don't want it getting too cold (i.e. below 10C), even when I'm not
there.

If your house normally drops from say 20C in the morning to 10C by the
evening, I'd say you desperately need the insulation sorted.

Nah, it doesn't. In fact, despite lack of wall insulation, it doesn't drop
that much during the day. However, during the night, it could well go below
10C. Wall insulation isn't practical. It has solid walls and original
features that would get seriously disturbed. However, as it is a terraced
house, the overall heat loss really isn't that bad in practical terms.

Christian.

In article ,
Christian McArdle wrote:
If your house normally drops from say 20C in the morning to 10C by the
evening, I'd say you desperately need the insulation sorted.

Nah, it doesn't. In fact, despite lack of wall insulation, it doesn't
drop that much during the day. However, during the night, it could well
go below 10C. Wall insulation isn't practical. It has solid walls and
original features that would get seriously disturbed. However, as it is
a terraced house, the overall heat loss really isn't that bad in
practical terms.

Much the same as mine, then. But I'm not intererested too much in the
nighttime temp as I'm in bed. ;-) Obviously, if it can't come up to
temperature after the switch on time and I get up, then that's when I'd
leave it on all night - controlled to the nighttime temp of the stat. But
it's not many times a year.

--
*I don't know what your problem is, but I'll bet it's hard to pronounce

Dave Plowman London SW 12
RIP Acorn

Lurch wrote:



So in general then to the OP, yes, your way would work but there are
other ways, a good programmable room stat would be my choice coupled
with a single channel on the water, but it's a free country!

Now you've lost me....there are other ways but you'd recommend a good
programmable stat with a single channel on the water. Which is what i
was described in my original post.

Aj

Christian McArdle wrote:

Why use a programmable room stat if there is already a 2 channel
programmer, surely a standard wireless stat will suffice.
I've had one on a combi for the last 3 years so can confirm:
Several reasons. Basically, the advantages of using a programmable stat over
a separate stat and programmer a
1. Controls are in the living area rather than in a manky undersink cupboard
or inaccessible airing cupboard. This enables manual override and
programming to be easily achieved.

Generally the heating gets extra time if we stay up late. We're usually
in the living room in that case. A minor point - if the controls
stayed in the kitchen it would hardly be a problem, especially with
'boost' functions rather than just on/off.
2. Rather than turning off completely, the stat can just turn down the
temperature, to say, 12C, ensuring that the house doesn't get freezing
overnight, or whilst you are out.

or more importantly while you're on holiday. The ACL has 3 settings
each day. By default it comes on in the morning and tries to get the
house to 20C, lets it cool to 16 during the day, back to 21 in the
evening and then down to 7 overnight (from what i remember). If you're
ill or feeling the cold for some reason it's simple to turn it up a
degree or two and it reverts to the normal settings at the next junction.

3. Complex control laws can be used that can predict the house's response to
heat, enabling temperature overshoot to be controlled and enabling the
device to predict how long before the required start period the heating
needs to be on
That's the plan. the claim is that it can save 10% of fuel bills and
with a solid walled, single glazed house you need all the savings you
can get!

Christian McArdle wrote:

Are there any pitfalls I haven't thought of?
Secondly, ensure that you have a cylinder thermostat. It sounds like you
have an S plan system. If no cylinder stat is present, you need to insert it
in series between the programmer "HW On" output and the hot water zone valve
motor live (normally brown) wire.

Right. NOw you've lost me. Where can i find out what an 's' plan
system is? Why do i need a cylinder stat if i dont have one at the moment?

Now you've lost me....there are other ways but you'd recommend a good
programmable stat with a single channel on the water. Which is what i
was described in my original post.

I think he got confused who said what...

Whether to use a single or twin channel programmer is a minor point. The
important thing is to check that you have a functioning cylinder stat. If
not, it is very simple to add.

Christian.

On Wed, 14 Jan 2004 17:10:13 +0000, Anthony James
wrote:

Lurch wrote:



So in general then to the OP, yes, your way would work but there are
other ways, a good programmable room stat would be my choice coupled
with a single channel on the water, but it's a free country!

Now you've lost me....there are other ways but you'd recommend a good
programmable stat with a single channel on the water. Which is what i
was described in my original post.

Which is exactly what I agreed with. In esscence my answer was- yes,
that will work perfectly satisfactorily. The problem with ba simple
question is it has many complex answers.
A 2 channel programmer coupled with a programmable room stat would
offer you more control and an increase in performance.
If you are doing it the latter way just make sure that the settings
are all at the optimum for your living situation and that you use a
quality stat, some of the cheaper ones aren't as accurate on the
temperature.



SJW
A.C.S. Ltd.

Secondly, ensure that you have a cylinder thermostat. It sounds like you
have an S plan system. If no cylinder stat is present, you need to insert it
in series between the programmer "HW On" output and the hot water zone valve
motor live (normally brown) wire.

Right. NOw you've lost me. Where can i find out what an 's' plan
system is? Why do i need a cylinder stat if i dont have one at the moment?

By the sounds of it there should be a cylinder stat, if there isn't
one it would be required to modulate the hot water temp. If you don't
have one at the mo you wont really see any benefits by having
efficient heating controls if the rest of the system is innefficient.
If you're thinking of entirely rewiring your heating system I would
have thought you would be able to tell what sytem you have.
If it is an S plan there should be the boiler flow coming into the
airing cupboard, through the pump, then teeing into two valves. The
outlet of the heating valve will go into the heating flow. The outlet
of the water valve will go to the HW tank.


SJW
A.C.S. Ltd.

in reply to both of you (I'm now at home):

There is a cylinder stat.
I've been looking at ACL/Drayton (Invensys Climate Control) kit. It
worked well in the past for me.

Lurch wrote:

If it is an S plan there should be the boiler flow coming into the
airing cupboard, through the pump, then teeing into two valves. The
outlet of the heating valve will go into the heating flow. The outlet
of the water valve will go to the HW tank.

The boiler, cylinder, pump and valves are all located in a large airing
cupboard on the first floor. The piping and wiring are complicated by
the addition of a large pump for a power shower in an en suite that
takes a seperate feed off the tank - there are a lot of pipes and wires
in one place!

Is there anywhere i can get good wiring/plumbing diagrams and an
explanation of 's' plan for reference?

On Wed, 14 Jan 2004 18:41:24 +0000, Anthony James
wrote:

Lurch wrote:

If it is an S plan there should be the boiler flow coming into the
airing cupboard, through the pump, then teeing into two valves. The
outlet of the heating valve will go into the heating flow. The outlet
of the water valve will go to the HW tank.

The boiler, cylinder, pump and valves are all located in a large airing
cupboard on the first floor. The piping and wiring are complicated by
the addition of a large pump for a power shower in an en suite that
takes a seperate feed off the tank - there are a lot of pipes and wires
in one place!

Is there anywhere i can get good wiring/plumbing diagrams and an
explanation of 's' plan for reference?




http://content.honeywell.com/uk/homes/systems.htm


There are more tech notes if you poke around on the site.
..andy

To email, substitute .nospam with .gl

On Wed, 14 Jan 2004 18:36:14 +0000, Anthony James
wrote:

in reply to both of you (I'm now at home):

There is a cylinder stat.
I've been looking at ACL/Drayton (Invensys Climate Control) kit. It
worked well in the past for me.

ACL's good stuff, I use them quite a bit. Decent price too. Fitted a
few RF3i's on combi's, not had any complaints yet. Some have been in
for 6/7 years.
The Tempus 7 would be the 2 channel clock you would want instead if
you're going to do it that way.


SJW
A.C.S. Ltd.

Lurch wrote:

The Tempus 7 would be the 2 channel clock you would want instead if
you're going to do it that way.

Indeed. I've come to the conclusion that it's worth paying for the top
end controllers as the premium is'nt great. Tempus 7 even has a holiday
mode - tell it you'll be back in a fortnight and it will have the
house nice and warm for your return.

"Anthony James" wrote in message
...
Christian McArdle wrote:

Are there any pitfalls I haven't thought of?
Secondly, ensure that you have a cylinder thermostat. It sounds like you
have an S plan system. If no cylinder stat is present, you need to insert it
in series between the programmer "HW On" output and the hot water zone valve
motor live (normally brown) wire.

Right. NOw you've lost me. Where can i find out what an 's' plan
system is? Why do i need a cylinder stat if i dont have one at the moment?

If you dont have a cylinder stat at the moment, my guess is that you have
gravity H/W. i.e. Your pump only drives the Central Heating.

In this case you will always generate H/W when the C/H is on,

Typically the boiler is supplied with power whenever the time switch is on. The
boiler starts whenever the water temperature falls below a certain point. The
room thermostat controls the pump, i.e. the room thermostat supplies power to
the pump whenever the room temp falls below a certain point.

If you just replace the room stat with a programmable one, you will have to
leave the boiler on all the time and therefore generate hot water all the time.

You could avoid this by either:

a) Fitting a Danfoss Randall TP9 Programmer/Room thermostat to replace both
your current programmer and room thermostat. Possibly very easy to install as
you may well be able to use existing wiring. Less than £60 from plumbworld. The
TP 9 allows six room temp changes and two on periods per day for H/W. Can be set
to use a different program at weekends.

b) Fitting a H/W tank stat and zone valve with micro switch (Honeywell C plan).
Requires plumbing work.
Arguable a better solution but you need to be careful plumbing wise to be sure
that you boiler wont mind having is ability to circulate water naturally
restricted.

c) Using and additional relay to supply power to the boiler when the pump is on.

Option a) can be upgraded to option b). Nothing would be wasted.

Michael Chare








all the time the time


powered up all the time

On Wed, 14 Jan 2004 23:12:44 +0000 (UTC), "Michael Chare"
wrote:

"Anthony James" wrote in message
...
Christian McArdle wrote:

Are there any pitfalls I haven't thought of?
Secondly, ensure that you have a cylinder thermostat. It sounds like you
have an S plan system. If no cylinder stat is present, you need to insert it
in series between the programmer "HW On" output and the hot water zone valve
motor live (normally brown) wire.

Right. NOw you've lost me. Where can i find out what an 's' plan
system is? Why do i need a cylinder stat if i dont have one at the moment?

If you dont have a cylinder stat at the moment, my guess is that you have
gravity H/W. i.e. Your pump only drives the Central Heating.

If you would care to read previous posts you would note that;

a) there are 2 zone valves already installed, so that puts gravity out
of the question.

b) there is a cylinder stat etc... (see a))

In this case you will always generate H/W when the C/H is on,

Typically the boiler is supplied with power whenever the time switch is on. The
boiler starts whenever the water temperature falls below a certain point. The
room thermostat controls the pump, i.e. the room thermostat supplies power to
the pump whenever the room temp falls below a certain point.

If you just replace the room stat with a programmable one, you will have to
leave the boiler on all the time and therefore generate hot water all the time.

You could avoid this by either:

a) Fitting a Danfoss Randall TP9 Programmer/Room thermostat to replace both
your current programmer and room thermostat. Possibly very easy to install as
you may well be able to use existing wiring. Less than £60 from plumbworld. The
TP 9 allows six room temp changes and two on periods per day for H/W. Can be set
to use a different program at weekends.

Already sorted that I think, wireless would guarantee no wiring would
be needed in addition to the stat.

b) Fitting a H/W tank stat and zone valve with micro switch (Honeywell C plan).
Requires plumbing work.
Arguable a better solution but you need to be careful plumbing wise to be sure
that you boiler wont mind having is ability to circulate water naturally
restricted.

c) Using and additional relay to supply power to the boiler when the pump is on.

Option a) can be upgraded to option b). Nothing would be wasted.

If it were me who asked the original question I would ignore all of
this as irrelevant or incorrect.


SJW
A.C.S. Ltd.

"Lurch" wrote in message
...
On Wed, 14 Jan 2004 23:12:44 +0000 (UTC), "Michael Chare"
wrote:

"Anthony James" wrote in message
...
Christian McArdle wrote:

Are there any pitfalls I haven't thought of?
Secondly, ensure that you have a cylinder thermostat. It sounds like you
have an S plan system. If no cylinder stat is present, you need to insert
it
in series between the programmer "HW On" output and the hot water zone
valve
motor live (normally brown) wire.

Right. NOw you've lost me. Where can i find out what an 's' plan
system is? Why do i need a cylinder stat if i dont have one at the moment?

If you dont have a cylinder stat at the moment, my guess is that you have
gravity H/W. i.e. Your pump only drives the Central Heating.

If you would care to read previous posts you would note that;

a) there are 2 zone valves already installed, so that puts gravity out
of the question.

b) there is a cylinder stat etc... (see a))

Maybe I have paid more attention to the O/P's statement that he does not have a
Cylinder stat
than to your argument that he ought to have one.

Michael Chare

--

Regards

Michael Chare
"Michael Chare" wrote in message
...
"Lurch" wrote in message
...
On Wed, 14 Jan 2004 23:12:44 +0000 (UTC), "Michael Chare"
wrote:

"Anthony James" wrote in message
...
Christian McArdle wrote:

Are there any pitfalls I haven't thought of?
Secondly, ensure that you have a cylinder thermostat. It sounds like
you
have an S plan system. If no cylinder stat is present, you need to
insert
it
in series between the programmer "HW On" output and the hot water zone
valve
motor live (normally brown) wire.

Right. NOw you've lost me. Where can i find out what an 's' plan
system is? Why do i need a cylinder stat if i dont have one at the
moment?

If you dont have a cylinder stat at the moment, my guess is that you have
gravity H/W. i.e. Your pump only drives the Central Heating.

If you would care to read previous posts you would note that;

a) there are 2 zone valves already installed, so that puts gravity out
of the question.

b) there is a cylinder stat etc... (see a))

Maybe I have paid more attention to the O/P's statement that he does not have
a
Cylinder stat
than to your argument that he ought to have one.

Having looked looked up that particularly boiler I concede he cant/should not
have a gravity sytem.
D' uh.

Michael Chare

"Michael Chare" wrote in message
...

Having looked looked up that particularly boiler I concede he cant/should
not
have a gravity sytem.

At which point I become confused again. I do have a cold water tank in the
loft - i was under the impression this was a sign of a gravity fed system?
I'm coming to the conclusion that it might be time to get a heating engineer
in - having owned combi's for the last 10 years i'm rusty on everything
else.

AJ

In article ,
Anthony James wrote:
Having looked looked up that particularly boiler I concede he
cant/should not have a gravity sytem.

At which point I become confused again. I do have a cold water tank in
the loft - i was under the impression this was a sign of a gravity fed
system?

Think a gravity system is where the hot water circuit isn't pumped. If
you've got motorised valves etc, it probably is.

--
*When everything's coming your way, you're in the wrong lane *

Dave Plowman London SW 12
RIP Acorn

On Thu, 15 Jan 2004 23:44:44 +0000 (GMT), Dave Plowman
wrote:

In article ,
Anthony James wrote:
Having looked looked up that particularly boiler I concede he
cant/should not have a gravity sytem.

At which point I become confused again. I do have a cold water tank in
the loft - i was under the impression this was a sign of a gravity fed
system?

Think a gravity system is where the hot water circuit isn't pumped. If
you've got motorised valves etc, it probably is.

You can have a C plan set up where the boiler/DHW cylinder circuit is
gravity (meaning convection) and a zone valve and thermostat are used
to prevent the hot water from overheating.



..andy

To email, substitute .nospam with .gl

In article ,
Andy Hall wrote:
Think a gravity system is where the hot water circuit isn't pumped. If
you've got motorised valves etc, it probably is.

You can have a C plan set up where the boiler/DHW cylinder circuit is
gravity (meaning convection) and a zone valve and thermostat are used
to prevent the hot water from overheating.

Hence my use of 'probably'. I'm sure it's possible, but I've never seen it.

More common was a sort of TRV to control the water temperature, rather
than just the boiler stat.

--
*Why is the third hand on the watch called a second hand?

Dave Plowman London SW 12
RIP Acorn