roberth1 wrote:

Thought the anwer would be to get a wireless programmable digital
thermostat but on reading all the installation instructions vial
downloads none of them appear to be able to send a signal to just have
HW on like in the summer time for example.

The wireless stat only controls the CH, not the HW. The HW would still
be controlled by the timer (and also a HW stat which is really just
there to shut off the boiler, to stop the water getting too hot).

I did exactly what you are describing recently. I got a two-channel
clock (Honeywell ST6400C) and a wireless stat (Honeywell CM67). The
ST6400C turns the hot water on or off independently of the room stat
turning the heating on and off. On the ST6400 timeclock I've programmed
the heating to be "always on"; the CM67 is connected in series so the
heating is only on when the stat requests it.

The secret to making it all work is to get a mid-position three-port valve.

It would be very handy to have a stat combined with a wireless
programmer which would allow you to control everything from one place,
but nobody seems to make anything like this.

In my case it would just
mean a signal to activate the boiler to "on" as the HW would then be
heated.
I do not have a problem with the upstairs rads getting hot as these are
all fitted with thermo valves.

Yeah, but that's not as efficient as having more precise control, which
you can have by marrying a two-channel programmer and a stat as
described above.

I have A CH system with gravity HW with a mechanical cylinder stat. and the heating controlled by a 2 wire mechanical thermostat.
The Controller is mounted near boiler which is not easily accesible.
Gas fired boiler replaced in past 3 years.

Wanted to both change the thermostat to a digital one to get more accuracy and at the same time introduce more flexibility into the system to replace existing controller which is of the conventional HW or HW+CH "auto" "twice daily""continuous" type

Thought the anwer would be to get a wireless programmable digital thermostat but on reading all the installation instructions vial downloads none of them appear to be able to send a signal to just have HW on like in the summer time for example. In my case it would just mean a signal to activate the boiler to "on" as the HW would then be heated.
I do not have a problem with the upstairs rads getting hot as these are all fitted with thermo valves.

Anyone any idea how to arrange this, my thoughts are leaning to the 2 zone type receivers and using the second zone as the hot water on but think this may still end up calling the pump.

There must be a lot of CH systems like mine and I cannot understand why the makers of the wireless programmers have not addressed this HW problem.

Grateful for any ideas from anyone.

Lot of talk of what can and can't be done,
to make it simple, as you are upgrading the wiring then you
have to comply with Part L of the current building regs.

This states you must have a means of controlling
your CH & HW seperatley.

If I were you, I would get someone who knows what they are doing
and is also certified under Part P of the building regs to
do the work.

As you are upgrading the wiring, you would also be liable
to upgrade the earthing of the central heating system and also
making sure your gas and water are bonded also.

Things have got so silly now, that from the 1st may 2006 you are
not allowed toalter or fit a new soil waste or bath without notifying
you local building control at your local council, and you have to pay
to have it inspected.....


ALWAYS BEST TO GET THE JOB DONE BY A PROFESSIONAL

In an earlier contribution to this discussion,
roberth1 wrote:

I have A CH system with gravity HW with a mechanical cylinder stat.
and the heating controlled by a 2 wire mechanical thermostat.
The Controller is mounted near boiler which is not easily accesible.
Gas fired boiler replaced in past 3 years.

Wanted to both change the thermostat to a digital one to get more
accuracy and at the same time introduce more flexibility into the
system to replace existing controller which is of the conventional HW
or HW+CH "auto" "twice daily""continuous" type

Thought the anwer would be to get a wireless programmable digital
thermostat but on reading all the installation instructions vial
downloads none of them appear to be able to send a signal to just have
HW on like in the summer time for example. In my case it would just
mean a signal to activate the boiler to "on" as the HW would then be
heated.
I do not have a problem with the upstairs rads getting hot as these
are all fitted with thermo valves.

Anyone any idea how to arrange this, my thoughts are leaning to the 2
zone type receivers and using the second zone as the hot water on but
think this may still end up calling the pump.

There must be a lot of CH systems like mine and I cannot understand
why the makers of the wireless programmers have not addressed this HW
problem.

Grateful for any ideas from anyone.


With a gravity HW system, your options are very limited. In order to have
proper independent control of HW and CH - including a boiler interlock to
shut the boiler down when both demands are satisfied - you really need to
convert to a fully pumped solution.

There *is* an alternative which is nearly as good - but probably doesn't
fully comply with the latest regs. That involves inserting a zone valve in
the gravity HW circuit, and fitting a cylinder thermostat, and wiring it up
in line with Honeywell's C-Plan configuration. That would, indeed, provide a
boiler interlock and would be far superior to what you have at present. It
would also involve a lot less plumbing and wiring than going fully pumped.
The only downside is the HW takes longer to get hot by gravity circulation
that it does when pumped - and the boiler is keeping itself hot for all that
time, using a bit more energy than it otherwise would.

I would post a URL where you could look at C-Plan (and other plans) - but
that bit of the Honeywell site isn't working at the moment. I'm not sure
whether that's by design or accident! Here's the URL anyway, just in case it
comes back on line.

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

Once you have independent control of HW and CH - whether it's by C-Plan,
S-Plan or Y-Plan, you can use wireless and/or programmable stats rather than
conventional stats if that is more convenient. A solution which works for
many people is to have the HW controlled by the main programmer, plus a
mechanical cylinder stat - and the CH controlled by a wired or wireless
programmable stat so that you can have different temperatures at different
times of the day, together with other gizmos likes party and holiday modes.
--
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 message , "Billy The Kid
( The Original )" writes
Lot of talk of what can and can't be done,
to make it simple, as you are upgrading the wiring then you
have to comply with Part L of the current building regs.

This states you must have a means of controlling
your CH & HW seperatley.

If I were you, I would get someone who knows what they are doing
and is also certified under Part P of the building regs to
do the work.

As you are upgrading the wiring, you would also be liable
to upgrade the earthing of the central heating system and also
making sure your gas and water are bonded also.

Things have got so silly now, that from the 1st may 2006 you are
not allowed toalter or fit a new soil waste or bath without notifying
you local building control at your local council, and you have to pay
to have it inspected.....


ALWAYS BEST TO GET THE JOB DONE BY A PROFESSIONAL

Is it buggery

****

--
geoff

The message
from "Billy The Kid ( The Original ) " contains
these words:

ALWAYS BEST TO GET THE JOB DONE BY A PROFESSIONAL

Oh dear. And what do you think the purpose of this group is?

--
Skipweasel
Pay no attention to that man behind the curtain.

"roberth1" wrote in message
...

I have A CH system with gravity HW with a mechanical cylinder stat. and
the heating controlled by a 2 wire mechanical thermostat.
The Controller is mounted near boiler which is not easily accesible.
Gas fired boiler replaced in past 3 years.

Have you considered using a Danfoss TP9 programmer. This is a two channel
programmer, which uses a wired remote room temperature sensor. . The H/W can
have two on periods each day. The C/H can have 6 temperature changes per day.
There can be separate weekday and weekend programmes.

There is a gravity option. In this case the boiler only gets power when either
the pump is running to heat the radiators or during the H/W on periods.

If you have an existing room thermostat, then likely you can replace it with the
TP9's sensor and use the existing wiring to connect back to the programmer
position.

You can download all the details from the Danfoss web site.

I've not found another programmer which works in the same way.

--

Michael Chare

"Roger Mills" wrote in message
...
In an earlier contribution to this discussion,
roberth1 wrote:

I have A CH system with gravity HW with a mechanical cylinder stat.
and the heating controlled by a 2 wire mechanical thermostat.
The Controller is mounted near boiler which is not easily accesible.
Gas fired boiler replaced in past 3 years.

Wanted to both change the thermostat to a digital one to get more
accuracy and at the same time introduce more flexibility into the
system to replace existing controller which is of the conventional HW
or HW+CH "auto" "twice daily""continuous" type

Thought the anwer would be to get a wireless programmable digital
thermostat but on reading all the installation instructions vial
downloads none of them appear to be able to send a signal to just have
HW on like in the summer time for example. In my case it would just
mean a signal to activate the boiler to "on" as the HW would then be
heated.
I do not have a problem with the upstairs rads getting hot as these
are all fitted with thermo valves.

Anyone any idea how to arrange this, my thoughts are leaning to the 2
zone type receivers and using the second zone as the hot water on but
think this may still end up calling the pump.

There must be a lot of CH systems like mine and I cannot understand
why the makers of the wireless programmers have not addressed this HW
problem.

Grateful for any ideas from anyone.


With a gravity HW system, your options are very limited. In order to have
proper independent control of HW and CH - including a boiler interlock to
shut the boiler down when both demands are satisfied - you really need to
convert to a fully pumped solution.

There *is* an alternative which is nearly as good - but probably doesn't
fully comply with the latest regs. That involves inserting a zone valve in
the gravity HW circuit, and fitting a cylinder thermostat, and wiring it
up

Best he installs a pump in the either the flow or return of the gravity
cylinder with a check valve just after the DHW and CH pumps. Minimum
pipework interruption. Then a cylinder stat and then a new programmer. The
Danfoss, as mentioned, is an excellent choice. Probably a box on the wall
to take a cheap £5 relay from Maplin.

"raden" wrote in message
...
In message , "Billy The Kid
( The Original )" writes
Lot of talk of what can and can't be done,
to make it simple, as you are upgrading the wiring then you
have to comply with Part L of the current building regs.

This states you must have a means of controlling
your CH & HW seperatley.

If I were you, I would get someone who knows what they are doing
and is also certified under Part P of the building regs to
do the work.

As you are upgrading the wiring, you would also be liable
to upgrade the earthing of the central heating system and also
making sure your gas and water are bonded also.

Things have got so silly now, that from the 1st may 2006 you are
not allowed toalter or fit a new soil waste or bath without notifying
you local building control at your local council, and you have to pay
to have it inspected.....


ALWAYS BEST TO GET THE JOB DONE BY A PROFESSIONAL

Is it buggery

****

Well said Maxie!!

On Tue, 18 Apr 2006 20:17:19 GMT, in uk.d-i-y "Billy The Kid ( The
Original ) " wrote:

[snip]

ALWAYS BEST TO GET THE JOB DONE BY A PROFESSIONAL

Shame. You were doing quite well up to here.