Hi all,

Just planning for conservatory self-build for which I'm sure there
will be many questions over the following weeks!

After much googling of uk.d-i-y it seems that extending the CH
pipework into the conservatory and plumbing into a decent finned
double rad is the way to go. The conservatory rad needs to be
controlled separately from the rest of the houses' CH as I may need
heat in the conservatory during periods when the main house stat is
not demanding heat and the boiler is therefore inactive.

Boiler is an ariston microgenus II31 combi. Control is by a battery
powered 2 wire programmable stat. Zoning is beyond my current level
of knowledge but I'm trying to plug that particular gap right now!
I'm guessing that I need to introduce a 3-port mid position valve to
the flow end of the CH and connect to it (a) the original house stat
and (b) a new stat to be located in the conservatory. The resulting 4
peices of wire (and this is where it gets a bit beyond me) I'm
guessing need to be connected to the valve in a configuration such
that continuity across circuit (a) opens the valve to position a,
circuit (b) opens to position b and (a and b) opens a+b. I think I'm
correct in understanding that the valve will also act as a relay so
that a single connection from the valve to the boiler can be used to
tell the boiler that CH heat is being demanded.

I wonder if anyone could confirm (or not) that I'm barking up the
right tree here. The bit I need further information on is the wiring.
Does anyone have any good pointers to where I may learn about this?

Thanks

Mike

On Fri, 30 Sep 2005 23:53:42 GMT, Army
scrawled:

I'm guessing that I need to introduce a 3-port mid position valve to
the flow end of the CH

You guessed wrong! You want 2 2 port valves in the flow below the
boiler, or before the first tee off, for the house and conservatory
zones.

I wonder if anyone could confirm (or not) that I'm barking up the
right tree here. The bit I need further information on is the wiring.
Does anyone have any good pointers to where I may learn about this?

The wiring is much simplified doing it the correct way! The house stat
controls the valve for the house heating, the conservatory stat
controls the valve for the conservastory heating. The 2 sets of
auxilary contacts control the boiler.
--
Stuart @ SJW Electrical

Please Reply to group

"Lurch" wrote in message
news
On Fri, 30 Sep 2005 23:53:42 GMT, Army
scrawled:

I'm guessing that I need to introduce a 3-port mid position valve to
the flow end of the CH

You guessed wrong! You want 2 2 port valves in the flow below the
boiler, or before the first tee off, for the house and conservatory
zones.

I wonder if anyone could confirm (or not) that I'm barking up the
right tree here. The bit I need further information on is the wiring.
Does anyone have any good pointers to where I may learn about this?

The wiring is much simplified doing it the correct way! The house stat
controls the valve for the house heating, the conservatory stat
controls the valve for the conservastory heating. The 2 sets of
auxilary contacts control the boiler.

That's how mine works (except I have 5 2 port valves).

Wouldn't it work by just parallel wiring a new thermostat assuming the OP
has TRVs on all the radiators?

On Sat, 01 Oct 2005 07:09:49 GMT, "dennis@home"
scrawled:

Wouldn't it work by just parallel wiring a new thermostat assuming the OP
has TRVs on all the radiators?

No, because the 2 stats will not do the job they are intended, in
fact, I'm not really clear on exactly what you're suggesting but it
won't won't work anyway.
--
Stuart @ SJW Electrical

Please Reply to group

In an earlier contribution to this discussion,
Army wrote:

Zoning is beyond my current level
of knowledge but I'm trying to plug that particular gap right now!
I'm guessing that I need to introduce a 3-port mid position valve to
the flow end of the CH and connect to it (a) the original house stat
and (b) a new stat to be located in the conservatory.

You *could* do it with a 3-port valve but, as others have said, you'd be
better off with two 2-port valves.

Have a look at the 'plans' and their associated wiring diagrams in
http://content.honeywell.com/uk/homes/systems.htm

None of them exactly match your setup - but you should get some clues.

The Y-Plan is the one with the 3-port mid-position valve. It is intended to
give independent control of HW and CH in a setup with stored hot water,
rather than a combi. Note that the tank stat in the HW circuit has a
changeover switch with 3 contacts rather than a simple on/off switch. If you
use this setup to control two heating zones rather than HW + CH, it *will*
work - but whichever heating zone is in place of HW *must* have a changeover
thermostat.

The S-Plan (and S-Plan-Plus) are the ones which use 2-port valves. You can
have as many zones as you like, with one valve per zone. The motor of each
valve is controlled by a timer and stat for the appropriate zone or, even
better, by a programmable stat. The secondary contacts on each valve - which
close when the valve opens - are all connected in parallel and used to fire
up the boiler and run the pump whenever one or more valves are open. The
S-Plan shown in the Honeywell diagram (see URL above) shows a HW zone and a
CH zone - but will work just as well for two heating zones.
--
Cheers,
Set Square
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"Lurch" wrote in message
...
On Sat, 01 Oct 2005 07:09:49 GMT, "dennis@home"
scrawled:

Wouldn't it work by just parallel wiring a new thermostat assuming the OP
has TRVs on all the radiators?

No, because the 2 stats will not do the job they are intended, in
fact, I'm not really clear on exactly what you're suggesting but it
won't won't work anyway.

If you have TRVs on all the radiators then all you need to know is if the
conservatory needs heat.
If it does you fire the boiler.
You do this by putting a second stat in parallel with the room stat.
In fact you could have several stats if the layout needs it.

I think its a bodge but TRVs are a bodge anyway.

In an earlier contribution to this discussion,
dennis@home wrote:


If you have TRVs on all the radiators then all you need to know is if
the conservatory needs heat.
If it does you fire the boiler.
You do this by putting a second stat in parallel with the room stat.
In fact you could have several stats if the layout needs it.

I think its a bodge but TRVs are a bodge anyway.

Yes, but don't forget that the room in the house where the original room
stat is located *won't* (or *shouldn't* at any rate!) have a TRV on its
radiator. Using your system, that rad will get hot when the boiler fires to
heat the conservatory - even if the rest don't.

Also - unless the conservatory rad has a TRV - which will fight with its
room stat if it *does* - the conservatory will get heated when the rest of
the house is being heated, even if not required.

Positive zoning using motorised valve(s) would be far better - and would
almost certainly be *required* if the setup needs to meet current building
regs. Your solution is a recipe for heating *everything* whenever *anything*
needs heating!
--
Cheers,
Set Square
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"Set Square" wrote in message
...
In an earlier contribution to this discussion,
dennis@home wrote:


If you have TRVs on all the radiators then all you need to know is if
the conservatory needs heat.
If it does you fire the boiler.
You do this by putting a second stat in parallel with the room stat.
In fact you could have several stats if the layout needs it.

I think its a bodge but TRVs are a bodge anyway.

Yes, but don't forget that the room in the house where the original room
stat is located *won't* (or *shouldn't* at any rate!) have a TRV on its
radiator. Using your system, that rad will get hot when the boiler fires
to
heat the conservatory - even if the rest don't.

I did say TRV on all.


Also - unless the conservatory rad has a TRV - which will fight with its
room stat if it *does* - the conservatory will get heated when the rest of
the house is being heated, even if not required.

The TRV needs to be set slightly higher than the room stat.


Positive zoning using motorised valve(s) would be far better - and would
almost certainly be *required* if the setup needs to meet current building
regs.

I agree, zone valves with end switches is easy and how I have done mine.
However it was designed properly not some bodge dreamed up by a committee
like TRVs were.

Your solution is a recipe for heating *everything* whenever *anything*
needs heating!

No it will only heat if one of the stats calls for heat just like most
systems with TRVs.

In an earlier contribution to this discussion,
dennis@home wrote:

"Set Square" wrote in message
...
In an earlier contribution to this discussion,
dennis@home wrote:


Your solution is a recipe for heating *everything* whenever
*anything* needs heating!

No it will only heat if one of the stats calls for heat just like most
systems with TRVs.

The problem is that it will heat *both* zones when *either* zone is calling
for heat rather than just heating the desired zone. You might effect some
damage limitation by having TRVs set higher that the room stats - but that's
pretty hit and miss, and still an *almighty* bodge!
--
Cheers,
Set Square
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"Set Square" wrote in message
...
In an earlier contribution to this discussion,
dennis@home wrote:

"Set Square" wrote in message
...
In an earlier contribution to this discussion,
dennis@home wrote:


Your solution is a recipe for heating *everything* whenever
*anything* needs heating!

No it will only heat if one of the stats calls for heat just like most
systems with TRVs.

The problem is that it will heat *both* zones when *either* zone is
calling
for heat rather than just heating the desired zone. You might effect some
damage limitation by having TRVs set higher that the room stats - but
that's
pretty hit and miss, and still an *almighty* bodge!

Like I said that's how TRV based systems work.
The room stat has to be in the warmest room and switch the system on even if
only that room wants heat.
That's why I think they are cr@p.
But if the system already works like that then its reasonable to extend it
in a similar way.

The only real problem is if the room stat is set higher than the TRV.
Then the pump will run continuously.
Even that may not be too bad if the pipes are insulated.

In an earlier contribution to this discussion,
dennis@home wrote:

But if the system already works like that then its reasonable to
extend it in a similar way.

No it isn't!

The conservatory will get heated to its TRV setting even when *no* heating
is required - as will the room in the house with the room stat - when *only*
the conservatory is required to be heated.

The difference is that when you want to heat the house, you are presumed to
want to heat the
*whole* house (without conservatory) - and the current TRV solution makes a
reasonable job of that. As soon as you introduce another zone which requires
*independent* control, the whole thing falls down unless you zone it
properly.

Simply wiring two stats in parallel *WILL NOT* meet the OP's requirements.
--
Cheers,
Set Square
______
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"Set Square" wrote in message
...
In an earlier contribution to this discussion,
dennis@home wrote:

But if the system already works like that then its reasonable to
extend it in a similar way.

No it isn't!

The conservatory will get heated to its TRV setting even when *no* heating
is required - as will the room in the house with the room stat - when
*only*
the conservatory is required to be heated.

Yes.


The difference is that when you want to heat the house, you are presumed
to
want to heat the
*whole* house (without conservatory) - and the current TRV solution makes
a
reasonable job of that. As soon as you introduce another zone which
requires
*independent* control, the whole thing falls down unless you zone it
properly.

Why would anyone want to heat a whole house?
Why would anyone not want to be able to walk into the conservatory in the
midle of winter without waiting two hours for the heating to work?
He might want it for frost prevention in which case heating the whole house
would be fine.


Simply wiring two stats in parallel *WILL NOT* meet the OP's requirements.

Neither of us knows the answer to that question.

On Sun, 02 Oct 2005 19:57:03 GMT, "dennis@home"
scrawled:

Simply wiring two stats in parallel *WILL NOT* meet the OP's requirements.

Neither of us knows the answer to that question.

If you stop being a pillock and read the OP you'll find that Mr.
Squares statement is true, doing as you propose will not meet the OP's
requirements.
--
Stuart @ SJW Electrical

Please Reply to group

In an earlier contribution to this discussion,
dennis@home wrote:


Why would anyone want to heat a whole house?

You may not - in which case you would install some sort of zoning - such as
upstairs and downstairs, but the OP hasn't done that - so it's fair to
assume that he's happy for the whole house (excluding the conservatory) to
be heated as an entity.

Why would anyone not want to be able to walk into the conservatory in
the midle of winter without waiting two hours for the heating to work?

Surely, that's the whole point of zoning! If you have independent control of
the heating in the conservatory, you can have *just* that on - and use as
much of the boiler's output as the conservatory radiator can absorb. Why
should this take two hours? It can be on a timer, to be hot when required,
anyway!


Simply wiring two stats in parallel *WILL NOT* meet the OP's
requirements.

Neither of us knows the answer to that question.

Then let me remind you of what the OP said in the initial post, namely:

"The conservatory rad needs to be controlled separately from the rest of the
houses' CH as I may need heat in the conservatory during periods when the
main house stat is not demanding heat and the boiler is therefore inactive."

He clearly therefore needs to be able to heat *just* the conservatory
without heating *any* part of the house at the same time.

I rest my case!
--
Cheers,
Set Square
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"Set Square" wrote in message
...

Then let me remind you of what the OP said in the initial post, namely:

"The conservatory rad needs to be controlled separately from the rest of
the
houses' CH as I may need heat in the conservatory during periods when the
main house stat is not demanding heat and the boiler is therefore
inactive."

He clearly therefore needs to be able to heat *just* the conservatory
without heating *any* part of the house at the same time.

No he actually states that the stat in the rest of the house will be off so
he gets no heat from the boiler.
Adding a second stat gets around this.
The OP may well be happy to turn the stat and TRV on and off.


I rest my case!

Shame as you didn't read what you quoted.

In an earlier contribution to this discussion,
dennis@home wrote:


Shame as you didn't read what you quoted.

That's precisely what I *did* do!

It's a shame that you're not big enough to accept that what you suggested is
a damn silly idea - rather than continuing to try to defend the
indefensible! I haven't noticed anyone else agreeing with you - not even Dr
Drivel. g
--
Cheers,
Set Square
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"Set Square" wrote in message
...
In an earlier contribution to this discussion,
dennis@home wrote:


Shame as you didn't read what you quoted.

That's precisely what I *did* do!

Then read it properly.


It's a shame that you're not big enough to accept that what you suggested
is
a damn silly idea - rather than continuing to try to defend the
indefensible!

I wouldn't do it (my house has five zone valves including the conservatory
each fed from a timer stat.).
But it does allow the OP to get heat even if the room stat is off.
This is what the OP said was his problem.

If he wants to do the job properly and fit zones then he can do so.
If all he wants is an override for the room stat then what I said will work
too.
If he only wants to heat it for frost protection purposes then it is
probably the easiest way and easiest is invariablly the correct way in my
experience.

I haven't noticed anyone else agreeing with you

Most people don't care and are bored, just like me.

- not even Dr Drivel. g

That would be evidence for me being correct then.

In article , Army
writes

I wonder if anyone could confirm (or not) that I'm barking up the
right tree here. The bit I need further information on is the wiring.
Does anyone have any good pointers to where I may learn about this?

In case you were in any doubt, the advice of Mr Square, supported by Mr
Lurch is sound, the other is er, not :-).
--
fred

In an earlier contribution to this discussion,
fred wrote:

In article , Army
writes

I wonder if anyone could confirm (or not) that I'm barking up the
right tree here. The bit I need further information on is the
wiring. Does anyone have any good pointers to where I may learn
about this?

In case you were in any doubt, the advice of Mr Square, supported by
Mr Lurch is sound, the other is er, not :-).

Indeed, in my post of 5:16pm on 1st October, I gave a reference to a
Honeywell site showing various heating plans with their associated wiring
diagrams, and explained that and S-Plan arrangement would be best - but also
explained how a Y-Plan could be adapted to suit the OP's needs if he really
wants to use a 3-port valve.

This information should be sufficient to enable any competent DIY-er to sort
out the wiring.
--
Cheers,
Set Square
______
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In an earlier contribution to this discussion,
dennis@home wrote:


If he wants to do the job properly and fit zones then he can do so.
If all he wants is an override for the room stat then what I said
will work too.

But there is no evidence that that is *all* he wants.

On the contrary, why would he mention *separate* control of the
conservatory, and *zoning* and *motorised valves* if all he wanted to do was
to over-ride the room stat? He clearly had something slightly more ambitious
in mind! And, as I have said so many times that I am becoming blue in the
face, what you suggested *won't* work in a satisfactory fashion.

Meanwhile, we've almost certainly succeeded in confusing the poor sod with
all these red herrings about wiring stats in parallel. He hasn't been back,
anyway!
--
Cheers,
Set Square
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"dennis@home" wrote:


Like I said that's how TRV based systems work.
The room stat has to be in the warmest room and switch the system on even if
only that room wants heat.

No they don't. There is nothing to stop a thermostat being located
*anywhere* where it will receive the appropriate amount of output from
the heating system. Lots of thermostats are located in hallways with
no TRV's on the rads and controlling to a much *lower* temp than the
main living areas. As long as the rads are sized correctly, the
thermal losses through the structure are not wildly different, the
outer doors are not opened on a too regular basis and doors from an
area with a higher desired temperature are usually kept closed then
they function well.

--

"Set Square" wrote in message
...
In an earlier contribution to this discussion,
dennis@home wrote:


If he wants to do the job properly and fit zones then he can do so.
If all he wants is an override for the room stat then what I said
will work too.

But there is no evidence that that is *all* he wants.

Well he has already been told how to do it using zone valves.
What i said was a cheap alternative.
Its not wrong it is just different.


On the contrary, why would he mention *separate* control of the
conservatory, and *zoning* and *motorised valves* if all he wanted to do
was
to over-ride the room stat? He clearly had something slightly more
ambitious
in mind! And, as I have said so many times that I am becoming blue in the
face, what you suggested *won't* work in a satisfactory fashion.

Meanwhile, we've almost certainly succeeded in confusing the poor sod with
all these red herrings about wiring stats in parallel. He hasn't been
back,
anyway!

Yes he has.

"Matt" wrote in message
...
"dennis@home" wrote:


Like I said that's how TRV based systems work.
The room stat has to be in the warmest room and switch the system on even
if
only that room wants heat.

No they don't. There is nothing to stop a thermostat being located
*anywhere* where it will receive the appropriate amount of output from
the heating system. Lots of thermostats are located in hallways with
no TRV's on the rads and controlling to a much *lower* temp than the
main living areas. As long as the rads are sized correctly, the
thermal losses through the structure are not wildly different, the
outer doors are not opened on a too regular basis and doors from an
area with a higher desired temperature are usually kept closed then
they function well.

No they don't.
Say you put the stat in the hall and set it to 15C as the temperature you
want in the hall.
Then the system will not provide any heat until the outside temp drops well
below 15C and the hall catches up.
I.e. no room set to a higher temp will get any heat until the temperature
has dropped well below what the owner actually wants.
In fact if the outside sits at 16C the rest of the house will also sit at
16C and the heating will not turn on.

Now go and think about where the correct place to put a room stat is.

"Set Square" wrote in message
...
In an earlier contribution to this discussion,
fred wrote:

In article , Army
writes

I wonder if anyone could confirm (or not) that I'm barking up the
right tree here. The bit I need further information on is the
wiring. Does anyone have any good pointers to where I may learn
about this?

In case you were in any doubt, the advice of Mr Square, supported by
Mr Lurch is sound, the other is er, not :-).

Indeed, in my post of 5:16pm on 1st October, I gave a reference to a
Honeywell site showing various heating plans with their associated wiring
diagrams, and explained that and S-Plan arrangement would be best - but
also
explained how a Y-Plan could be adapted to suit the OP's needs if he
really
wants to use a 3-port valve.

This information should be sufficient to enable any competent DIY-er to
sort
out the wiring.

You could have done it better:-

Find somewhere to break into the flow from the boiler.
Tee in two zone valves one to feed the original circuit.
One to feed the conservatory.

Fit a bypass pipe between the flow and the return before the zone valves
(very important on most systems!).

Wire the room stat to the one valve.
Wire a new room stat to the valve for the conservatory.

Take a live feed to the end switches on the valves and wire the other
terminals to boiler on.

Now don't forget that you need to be an certificating electrician to do it
legally.

In an earlier contribution to this discussion,
dennis@home wrote:

"Set Square" wrote in message
...

But there is no evidence that that is *all* he wants.

Well he has already been told how to do it using zone valves.
What i said was a cheap alternative.
Its not wrong it is just different.

And crap!


Meanwhile, we've almost certainly succeeded in confusing the poor
sod with all these red herrings about wiring stats in parallel. He
hasn't been back,
anyway!

Yes he has.

When? The OP was "Army ". I can't find any more posts
by him in this thread!
--
Cheers,
Set Square
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wrote in message ...
On 3 Oct,
"dennis@home" wrote:


In fact if the outside sits at 16C the rest of the house will also sit at
16C and the heating will not turn on.


Currently the outside temparature has not exceeded 16C for several days,
and
has dropped much lower at night. The house has remained mostly above 21C
with
a low point of 18C overnight.

The difference is due to solar gain, and general occupancy of the house,
good
insulation, and not due to any deliberate heating.

Yes.
and how does that effect what I said?

"dennis@home" wrote:


"Matt" wrote in message
.. .
"dennis@home" wrote:


Like I said that's how TRV based systems work.
The room stat has to be in the warmest room and switch the system on even
if
only that room wants heat.

No they don't. There is nothing to stop a thermostat being located
*anywhere* where it will receive the appropriate amount of output from
the heating system. Lots of thermostats are located in hallways with
no TRV's on the rads and controlling to a much *lower* temp than the
main living areas. As long as the rads are sized correctly, the
thermal losses through the structure are not wildly different, the
outer doors are not opened on a too regular basis and doors from an
area with a higher desired temperature are usually kept closed then
they function well.

No they don't.
Say you put the stat in the hall and set it to 15C as the temperature you
want in the hall.
Then the system will not provide any heat until the outside temp drops well
below 15C and the hall catches up.
I.e. no room set to a higher temp will get any heat until the temperature
has dropped well below what the owner actually wants.
In fact if the outside sits at 16C the rest of the house will also sit at
16C and the heating will not turn on.

Now go and think about where the correct place to put a room stat is.

A huge number of systems have the thermostat in the hallway, Its not
the ideal place by a long way but if you site a thermostat in say the
main living area and this has a separate heat source like a gas fire
you can severely depress the temperature in the rest of the house.

One of the key factors in hallway siting is to get the radiator sized
correctly. If that is done then the boiler will run until the
thermostat is satisfied, if the radiator sizes are correct elsewhere
in the house then their requirements will be met. Make the hallway
super insulated, fit it with a radiator sized at 250% of the
requirements, fit the thermostat 2 inches above the radiator and it
will be a dogs dinner.

No one except you was ever advocating a 15 deg C thermostat setting, a
more practical 18 or 20 deg C - just below the main occupancy rooms
is required. The main rooms will still stick at 18 deg C forever and a
day with no boiler firing because of the lack of thermostat call, BUT
a thermostat sited in a main living area set to 23 deg C with
additional heat sources present could conversely in extreme conditions
leave a bedroom at 18 deg C below zero.


--

"Matt" wrote in message
...

No one except you was ever advocating a 15 deg C thermostat setting, a
more practical 18 or 20 deg C - just below the main occupancy rooms
is required.


From your post

"
Lots of thermostats are located in hallways with
no TRV's on the rads and controlling to a much *lower* temp than the
main living areas.
"

So a much lower temp is well above 15C then.

The main rooms will still stick at 18 deg C forever and a
day with no boiler firing because of the lack of thermostat call, BUT
a thermostat sited in a main living area set to 23 deg C with
additional heat sources present could conversely in extreme conditions
leave a bedroom at 18 deg C below zero.


That is why you may need more than one stat wired in parallel.
Just like a frost stat is wired in parallel with the room stat.

Single room stat system are a bodge.
They offer almost no control.

In an earlier contribution to this discussion,
dennis@home wrote:


That is why you may need more than one stat wired in parallel.
Just like a frost stat is wired in parallel with the room stat.

Have you never heard of programmable stats - which can be programmed to work
at different temperatures at different times *and* act as frost stats in
their OFF state? No need for any parallel wiring if you use one of these.

And it is *never* appropriate to wire in stats in parallel - thus
controlling the *same* thing - as a substitute for controlling *different*
things, as in zones.
--
Cheers,
Set Square
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"Set Square" wrote in message
...
In an earlier contribution to this discussion,
dennis@home wrote:


That is why you may need more than one stat wired in parallel.
Just like a frost stat is wired in parallel with the room stat.

Have you never heard of programmable stats - which can be programmed to
work
at different temperatures at different times *and* act as frost stats in
their OFF state? No need for any parallel wiring if you use one of these.

Two parallel stats with a timer (the old way of doing it).
Yes I have four of them.


And it is *never* appropriate to wire in stats in parallel - thus
controlling the *same* thing - as a substitute for controlling *different*
things, as in zones.

So its never appropriate to have a frost stat then.

I think you are confused.

In an earlier contribution to this discussion,
dennis@home wrote:


And it is *never* appropriate to wire in stats in parallel - thus
controlling the *same* thing - as a substitute for controlling
*different* things, as in zones.

So its never appropriate to have a frost stat then.

I think you are confused.


No, *you* are confused! If you use a programmable stat, you don't *need* a
frost stat.

However, you *can* wire a room stat and a frost stat in parallel - that is
ok because you want to control the *same* thing - namely the house heating -
with both of them. When it's *not* ok is when you need to control two
*different* zones - as in the original question in this thread - when the
stats need to be independent, each controlling their own valve.

I suspect that you're *trying* to confuse us by introducing the concept of a
frost stat in parallel with a room stat in another attempt to justify your
half-baked scheme for this poor bloke's conservatory. Sadly, it won't wash!
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

"Set Square" wrote in message
...
In an earlier contribution to this discussion,
dennis@home wrote:


And it is *never* appropriate to wire in stats in parallel - thus
controlling the *same* thing - as a substitute for controlling
*different* things, as in zones.

So its never appropriate to have a frost stat then.

I think you are confused.


No, *you* are confused! If you use a programmable stat, you don't *need* a
frost stat.

I'm not confused.
I understand how they work and how to setup proper control systems.
You keep changing your mind.

However, you *can* wire a room stat and a frost stat in parallel - that is
ok because you want to control the *same* thing - namely the house
heating -
with both of them. When it's *not* ok is when you need to control two
*different* zones - as in the original question in this thread - when the
stats need to be independent, each controlling their own valve.

See you have changed it again.


I suspect that you're *trying* to confuse us by introducing the concept of
a
frost stat in parallel with a room stat in another attempt to justify your
half-baked scheme for this poor bloke's conservatory. Sadly, it won't
wash!

Its heating not a washer. ;-)

Anyway you forget the obvious...

Like you state that he may want to heat the conservatory but not the rest of
the house so requires a valve.
However if he is using the conservatory he probably doesn't want the house
cold does he.

You state that he may want to heat the house but not the conservatory.
If so he is at home so he may be happy to turn the TRV knob.

I stated that to get the heating to run in the house and in the conservatory
he would need two stats.
This is true for any building with large differences in the construction
and, hence, the heat loss.

I think you are confused.

Anyway I am bored so you can carry on if you want I am going to watch TV.

"Matt" who is Lord Hall wrote in message
...
"dennis@home" wrote:


"Matt" wrote in message
.. .
"dennis@home" wrote:


Like I said that's how TRV based systems work.
The room stat has to be in the warmest room and switch the system on
even
if
only that room wants heat.

No they don't. There is nothing to stop a thermostat being located
*anywhere* where it will receive the appropriate amount of output from
the heating system. Lots of thermostats are located in hallways with
no TRV's on the rads and controlling to a much *lower* temp than the
main living areas. As long as the rads are sized correctly, the
thermal losses through the structure are not wildly different, the
outer doors are not opened on a too regular basis and doors from an
area with a higher desired temperature are usually kept closed then
they function well.

No they don't.
Say you put the stat in the hall and set it to 15C as the temperature you
want in the hall.
Then the system will not provide any heat until the outside temp drops
well
below 15C and the hall catches up.
I.e. no room set to a higher temp will get any heat until the temperature
has dropped well below what the owner actually wants.
In fact if the outside sits at 16C the rest of the house will also sit at
16C and the heating will not turn on.

Now go and think about where the correct place to put a room stat is.

A huge number

Lord Hall, you don't know about these things.

In article , Set Square
writes
In an earlier contribution to this discussion,
fred wrote:

In article , Army
writes

I wonder if anyone could confirm (or not) that I'm barking up the
right tree here. The bit I need further information on is the
wiring. Does anyone have any good pointers to where I may learn
about this?

In case you were in any doubt, the advice of Mr Square, supported by
Mr Lurch is sound, the other is er, not :-).

This information should be sufficient to enable any competent DIY-er to sort
out the wiring.

Indeed, but methinks you are now being well & truly trolled :-/.
--
fred

"Doctor Drivel" wittered incorrectly:

"Matt" who is NOT Lord Hall wrote in message
.. .

Lord Hall, you don't know about these things.


--

In an earlier contribution to this discussion,
fred wrote:

In article , Set Square
writes
In an earlier contribution to this discussion,
fred wrote:

In article , Army
writes

I wonder if anyone could confirm (or not) that I'm barking up the
right tree here. The bit I need further information on is the
wiring. Does anyone have any good pointers to where I may learn
about this?

In case you were in any doubt, the advice of Mr Square, supported by
Mr Lurch is sound, the other is er, not :-).

This information should be sufficient to enable any competent DIY-er
to sort out the wiring.

Indeed, but methinks you are now being well & truly trolled :-/.

Your right - I'm opting out - this bloke dennis@home has *got* to be a mate
of Dr Drivel - if not an alias! Life's too short to waste any more time
refuting his ramblings.
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

On Mon, 03 Oct 2005 19:54:29 GMT, fred scrawled:

Indeed, but methinks you are now being well & truly trolled :-/.

Not from this angle he's not.
--
Stuart @ SJW Electrical

Please Reply to group

"Set Square" wrote:

Your right - I'm opting out - this bloke dennis@home has *got* to be a mate
of Dr Drivel - if not an alias! Life's too short to waste any more time
refuting his ramblings.

I had my doubts before over him, but then again I suspect everyone
(except me!)


--

"Matt" wrote in message
news
"Set Square" wrote:

Your right - I'm opting out - this bloke dennis@home has *got* to be a
mate
of Dr Drivel - if not an alias! Life's too short to waste any more time
refuting his ramblings.

I had my doubts before over him, but then again I suspect everyone
(except me!)

Lord Hall, stop making up people. You are Matt. No behave.

On Mon, 3 Oct 2005 11:31:30 +0100, "Set Square"
wrote:

In an earlier contribution to this discussion,
fred wrote:

In article , Army
writes

I wonder if anyone could confirm (or not) that I'm barking up the
right tree here. The bit I need further information on is the
wiring. Does anyone have any good pointers to where I may learn
about this?

In case you were in any doubt, the advice of Mr Square, supported by
Mr Lurch is sound, the other is er, not :-).

Indeed, in my post of 5:16pm on 1st October, I gave a reference to a
Honeywell site showing various heating plans with their associated wiring
diagrams, and explained that and S-Plan arrangement would be best - but also
explained how a Y-Plan could be adapted to suit the OP's needs if he really
wants to use a 3-port valve.

This information should be sufficient to enable any competent DIY-er to sort
out the wiring.

Hi Set Square, Lurch et all,

OP here, many thanks for all your helpful posts!

Set Square, your post at 17:16 on Oct-01 was very helpful thank you,
in particular your reference to the honeywell site was really usefull.
I've studied the wiring diagrams and that side of things is fairly
clear now. In order to further my education, a couple of questions
spring to mind if I may be so bold...

(1) Why is S-plan favoured over y-plan? Y Plan seems to be
considerably cheaper to implement (assuming a changeover stat is not
overly expensive) and neater (ie less clutter under the boiler and
disruption to pipework). Also, regarding failures, the Y plan is
never 'closed' so no chance of the pump being activated when both
circuits are off. (Clearly the boiler has a bypass if the above were
to occur on the s-plan). I guess I must be missing something here.

(2) What is a changeover stat?

(3) Why can the motorised valve(s) not be installed on the return
rather than the flow?

BTW, I don't have TRVs on any of the rads. We have lived in this
house for a year now and the system seems to hang together quite
nicely without them. In addition, most of the rads have microbore
into 'same-end' rad valves and I don't think I've seen TRVs in that
configuration before.

Thanks all


Mike