Some time back a number of people were installing Sauter valves on their CH
systems. I am looking initially at the BXL valve body and the AXCM 117 230v
actuator. Anyone find the best/cheapest dealer to buy from for one off
sales?

On 2008-05-25 12:22:06 +0100, "Doctor Drivel" said:

Some time back a number of people were installing Sauter valves on
their CH systems. I am looking initially at the BXL valve body and the
AXCM 117 230v actuator. Anyone find the best/cheapest dealer to buy
from for one off sales?

I bought a number of the motorised actuators a few years ago and
shopped around for the best price then. That came from Controls
Center (i.e. the specialised controls operation of Wolseley).

I am not sure that Controls Center exists as a separate operation any
longer. Possibly it has been consolidated with Plumb Center.


Do you mean AXCM 117? I can't see such a part number on their site.

The AXM series is the normal motorised drive in two versions:

- AXM117F series - fixed positions

- AXM117S series - continuous using a dc control signal.

It looks as though the F series has a 230v model.

"Andy Hall" wrote in message news:483956c1@qaanaaq...
On 2008-05-25 12:22:06 +0100, "Doctor Drivel"
said:

Some time back a number of people were installing Sauter valves on their
CH systems. I am looking initially at the BXL valve body and the AXCM
117 230v actuator. Anyone find the best/cheapest dealer to buy from for
one off sales?

I bought a number of the motorised actuators a few years ago and shopped
around for the best price then. That came from Controls Center (i.e.
the specialised controls operation of Wolseley).

I am not sure that Controls Center exists as a separate operation any
longer. Possibly it has been consolidated with Plumb Center.

Do you mean AXCM 117? I can't see such a part number on their site.

Yep.

The AXM series is the normal motorised drive in two versions:

- AXM117F series - fixed positions

- AXM117S series - continuous using a dc control signal.

It looks as though the F series has a 230v model.

Here is the actuator. AXM 117 F200, 230v modulating actuator (230v one way,
230v the other way) - fixed positions until the controller decides to nudge
it along one way or the other.
http://www.sauterautomation.co.uk/pd...v_en435901.pdf

3-way BXL modulating valve body.
http://www.sauterautomation.co.uk/pd...s_en464072.pdf

Nothing on Plumb Centers site.

On 2008-05-25 13:40:59 +0100, "Doctor Drivel" said:


"Andy Hall" wrote in message news:483956c1@qaanaaq...
On 2008-05-25 12:22:06 +0100, "Doctor Drivel" said:

Some time back a number of people were installing Sauter valves on
their CH systems. I am looking initially at the BXL valve body and the
AXCM 117 230v actuator. Anyone find the best/cheapest dealer to buy
from for one off sales?

I bought a number of the motorised actuators a few years ago and
shopped around for the best price then. That came from Controls
Center (i.e. the specialised controls operation of Wolseley).

I am not sure that Controls Center exists as a separate operation any
longer. Possibly it has been consolidated with Plumb Center.

Do you mean AXCM 117? I can't see such a part number on their site.

Yep.

The AXM series is the normal motorised drive in two versions:

- AXM117F series - fixed positions

- AXM117S series - continuous using a dc control signal.

It looks as though the F series has a 230v model.

Here is the actuator. AXM 117 F200, 230v modulating actuator (230v one
way, 230v the other way) - fixed positions until the controller decides
to nudge it along one way or the other.
http://www.sauterautomation.co.uk/pd...v_en435901.pdf

3-way BXL modulating valve body.
http://www.sauterautomation.co.uk/pd...s_en464072.pdf

Nothing on Plumb Centers site.

OK, so it was AXM. F series.

I had to call Controls Center (as it was), plus a few others. These
were not stock items, but they came back with prices in an hour or so
and had next day availability.

If you're hoping to achieve a form of "analogue" control with an F
series, the results are not going to be all that good. I tried this
as a first experiment. The problem is that the actuator is
essentially dumb. It has no feedback mechanism and no self
calibration. Therefore all you can do is to run the motor to an end
stop and time how long it takes to reach the other end The trouble is
that an external controller won't know this, so it has to be done
visually and by listening to the actuator motor. I found that with
nudging it backwards and forwards without going to the ends, the
calibration was lost quite quickly, especially if the steps are small.
It can be improved by running the valve to an end stop periodically
and then going from there. Overall, it wasn't really satisfactory.

The S series doesn't give feedback to the controller either but does
have self calibration. This means that the valve will open to a
known position depending on applied control signal voltage. It does
its own periodic recalibration and is consistent.

"Andy Hall" wrote in message news:48396568@qaanaaq...
On 2008-05-25 13:40:59 +0100, "Doctor Drivel"
said:


"Andy Hall" wrote in message news:483956c1@qaanaaq...
On 2008-05-25 12:22:06 +0100, "Doctor Drivel"
said:

Some time back a number of people were installing Sauter valves on
their CH systems. I am looking initially at the BXL valve body and the
AXCM 117 230v actuator. Anyone find the best/cheapest dealer to buy
from for one off sales?

I bought a number of the motorised actuators a few years ago and shopped
around for the best price then. That came from Controls Center (i.e.
the specialised controls operation of Wolseley).

I am not sure that Controls Center exists as a separate operation any
longer. Possibly it has been consolidated with Plumb Center.

Do you mean AXCM 117? I can't see such a part number on their site.

Yep.

The AXM series is the normal motorised drive in two versions:

- AXM117F series - fixed positions

- AXM117S series - continuous using a dc control signal.

It looks as though the F series has a 230v model.

Here is the actuator. AXM 117 F200, 230v modulating actuator (230v one
way, 230v the other way) - fixed positions until the controller decides
to nudge it along one way or the other.
http://www.sauterautomation.co.uk/pd...v_en435901.pdf

3-way BXL modulating valve body.
http://www.sauterautomation.co.uk/pd...s_en464072.pdf

Nothing on Plumb Centers site.

OK, so it was AXM. F series.

I had to call Controls Center (as it was), plus a few others. These were
not stock items, but they came back with prices in an hour or so and had
next day availability.

Nothing on any Wolsey sites either. I think the Climate Center will be the
one.

If you're hoping to achieve a form of "analogue" control with an F series,
the results are not going to be all that good. I tried this as a first
experiment. The problem is that the actuator is essentially dumb. It
has no feedback mechanism and no self calibration.

I don't need feedback from the valve actuator. Just a simple 230v
modulating actuator. It is for a weather compensated rad circuit. The
compensator can switch the boiler burner (with in-built anti-cycle control)
or pulse a modulating valve one way or the other + or -. No feedback from
valve is needed as the valve position will be wherever it is positioned to
maintain setpoint.

The rad circuit is taken off a thermal store. A Smart pump on the flow and
TRVs all around.

Option 1. a 3-way domestic diverter valve - on/off not modulating. Drayton
make one with an end switch for around £35-40. 3-way valve on the return.
The compensator sense the return pipe as more stable temps on the return.
If compensator says the return should say, be 35C, and it is above setpoint
the 3-way valve is energised (by the compensator burner mode as it
anti-cycle) and the heating circuit pumps on itself until cooler and below
setpoint of 35C then the valve opens up again taking heat from a thermal
store and allowing cooler water into the bottom of the store. Either full
on or full off. Cheap and will work well enough. Maybe excessive wear on a
domestic 3-way valve motor, but should be OK. 35C water is placed at the
bottom of the thermal store to enhance condensing operation when the boiler
fires up to reheat the store. Most of the time the water will be below 30C
and the lower store temperature even cooler when DHW is draw off via a plate
heat exchanger returning very cool water (15 to 25C) back to the lower part
of the store. 70 to 80% of the latent heat is recovered when the boiler
return temp is 30C, 50% at 35C.

Option 2. A 3-way modulating valve, then ensures the return temperature
from the rads is accurate to what the compensator dictates by modulating the
valve. This ensures most of the time a trickle of cool water into the
bottom of the thermal store, maintaining thermal layering.

Condensing boiler efficiency is greatly raised and comfort conditions
enhanced by a feed-forward control weather compensator. TRVs trim off
locally.

If the Sauter 3-way valve and actuator are silly prices, I may go with the
3-way domestic diverter valve for ~£40.

Domestic 3-way mid-position valves stall the motor when in mid-position. I
could look at one of these to stall the motor at any position its travel. I
haven't looked seriously at this yet.

"Andy Hall" wrote in message news:48396568@qaanaaq...
On 2008-05-25 13:40:59 +0100, "Doctor Drivel"
said:


"Andy Hall" wrote in message news:483956c1@qaanaaq...
On 2008-05-25 12:22:06 +0100, "Doctor Drivel"
said:

Some time back a number of people were installing Sauter valves on
their CH systems. I am looking initially at the BXL valve body and the
AXCM 117 230v actuator. Anyone find the best/cheapest dealer to buy
from for one off sales?

I bought a number of the motorised actuators a few years ago and shopped
around for the best price then. That came from Controls Center (i.e.
the specialised controls operation of Wolseley).

I am not sure that Controls Center exists as a separate operation any
longer. Possibly it has been consolidated with Plumb Center.

Do you mean AXCM 117? I can't see such a part number on their site.

Yep.

The AXM series is the normal motorised drive in two versions:

- AXM117F series - fixed positions

- AXM117S series - continuous using a dc control signal.

It looks as though the F series has a 230v model.

Here is the actuator. AXM 117 F200, 230v modulating actuator (230v one
way, 230v the other way) - fixed positions until the controller decides
to nudge it along one way or the other.
http://www.sauterautomation.co.uk/pd...v_en435901.pdf

3-way BXL modulating valve body.
http://www.sauterautomation.co.uk/pd...s_en464072.pdf

Nothing on Plumb Centers site.

OK, so it was AXM. F series.

I had to call Controls Center (as it was), plus a few others. These were
not stock items, but they came back with prices in an hour or so and had
next day availability.

Nothing on any Wolsey sites either. I think the Climate Center will be the
one.

If you're hoping to achieve a form of "analogue" control with an F series,
the results are not going to be all that good. I tried this as a first
experiment. The problem is that the actuator is essentially dumb. It
has no feedback mechanism and no self calibration.

I don't need feedback from the valve actuator. Just a simple 230v
modulating actuator. It is for a weather compensated rad circuit. The
compensator can switch the boiler burner (with in-built anti-cycle control)
or pulse a modulating valve one way or the other + or -. No feedback from
valve is needed as the valve position will be wherever it is positioned to
maintain setpoint.

The rad circuit is taken off a thermal store directly. Condensing boiler
heats the store directly. A Smart pump on the flow and TRVs all around.

Option 1. a 3-way domestic diverter valve - on/off not modulating. Drayton
make one with an end switch for around £35-40. 3-way valve on the return.
The compensator sense the return pipe as more stable temps on the return.
If compensator says the return should say, be 35C, and it is above setpoint
the 3-way valve is energised (by the compensator burner mode as it
anti-cycle) and the heating circuit pumps on itself until cooler and below
setpoint of 35C then the valve opens up again taking heat from a thermal
store and allowing cooler water into the bottom of the store. Either full
on or full off. Cheap and will work well enough. Maybe excessive wear on a
domestic 3-way valve motor, but should be OK. 35C water is placed at the
bottom of the thermal store to enhance condensing operation when the boiler
fires up to reheat the store. Most of the time the water will be below 30C
and the lower store temperature even cooler when DHW is draw off via a plate
heat exchanger returning very cool water (15 to 25C) back to the lower part
of the store. 70 to 80% of the latent heat is recovered when the boiler
return temp is 30C, 50% at 35C.

Option 2. A 3-way modulating valve, then ensures the return temperature
from the rads is accurate to what the compensator dictates by modulating the
valve. This ensures most of the time a trickle of cool water into the
bottom of the thermal store, maintaining thermal layering.

Condensing boiler efficiency is greatly raised and comfort conditions
enhanced by a feed-forward control weather compensator. TRVs trim off
locally.

If the Sauter 3-way valve and actuator are silly prices, I may go with the
3-way domestic diverter valve for ~£40.

Domestic 3-way mid-position valves stall the motor when in mid-position. I
could look at one of these to stall the motor at any position its travel. I
haven't looked seriously at this yet.

On 2008-05-25 15:11:47 +0100, "Doctor Drivel" said:

Nothing on any Wolsey sites either. I think the Climate Center will be the
one.

Could be - seems to be the closest.

If the Sauter 3-way valve and actuator are silly prices, I may go with the
3-way domestic diverter valve for ~£40.

One-off is likely to be more than that but it's worth asking.



Domestic 3-way mid-position valves stall the motor when in mid-position. I
could look at one of these to stall the motor at any position its travel. I
haven't looked seriously at this yet.

On 25 May, 15:08, "Doctor Drivel" wrote:

Spartan or Sontay; neither of them do Sauter but I don'y know why
you'd want Sauter specifically. Sontay do 3-port rotary shoe Siebe
valves, but they've pasted their name over Siebe's on the on-line data
sheets. Siebe valves are good.

3-point floating control is the way many commercial mixing valves
work. The option is to have the control electronics in the controller
and have a cheaper valve actuator or have a 0-10V output from the
controller and an expensive actuator with the control electronics
inside it.

Forget 3-port mid-position valves; Sunvic do Mo-Mo valves that can be
adapted for modulating mixing use; they used to do some relay device
to adapt the standard valve. They've been having reliability issues
with their relays though, allegedly.

Option 1 is bolleaux. If you want on-off, too hot/too cold control of
the heating why not just do it with a thermostat. Diverter valve = 1
inlet, 2 outlets; I think you'd have to set that up as an injection
valve, but I'm sure you know what you're doing. ;-)
Option 2; sensible, conventional 3-port mixing. I have one as you
describe with a Siebe mixing valve; very good, if I do say so myself.
Option 3; variable speed injection mixing pump. No valve gland to wear
out. Very reliable, if you know how to do it properly. There's a good
article on the web, but ISTR you derided the author's technical
competence the last time I mentioned him, so I won't offend you by
giving the link here.
Option 4 as 2 but injection mixing valve. The way I'd go if I ever do
another one.

Some time back a number of people were installing Sauter valves on
their CH systems. *I am looking initially at the BXL valve body and the
AXCM 117 230v actuator. *Anyone find the best/cheapest dealer to buy
from for one off sales?

I bought a number of the motorised actuators a few years ago and shopped
around for the best price then. * *That came from Controls Center (i.e.
the specialised controls operation of Wolseley).

I am not sure that Controls Center exists as a separate operation any
longer. * Possibly it has been consolidated with Plumb Center.

Do you mean AXCM 117? * * *I can't see such a part number on their site.

Yep.

The AXM series is the normal motorised drive in two versions:

- AXM117F series - fixed positions

- AXM117S series - continuous using a dc control signal.

It looks as though the F series has a 230v model.

Here is the actuator. AXM 117 F200, 230v modulating actuator (230v one
way, 230v the other way) - fixed positions until the controller decides
to nudge it along one way or the other.
http://www.sauterautomation.co.uk/pd...v_en435901.pdf

3-way BXL modulating valve body.
http://www.sauterautomation.co.uk/pd...s_en464072.pdf

Nothing on Plumb Centers site.

OK, so it was AXM. F series.

I had to call Controls Center (as it was), plus a few others. * These were
not stock items, but they came back with prices in an hour or so and had
next day availability.

Nothing on any Wolsey sites either. I think the Climate Center will be the
one.

If you're hoping to achieve a form of "analogue" control with an F series,
the results are not going to be all that good. * *I tried this as a first
experiment. * * The problem is that the actuator is essentially dumb.. * It
has no feedback mechanism and no self calibration.

I don't need feedback from the valve actuator. *Just a simple 230v
modulating actuator. *It is for a weather compensated rad circuit. *The
compensator can switch the boiler burner (with in-built anti-cycle control)
or pulse a modulating valve one way or the other + or -. *No feedback from
valve is needed as the valve position will be wherever it is positioned to
maintain setpoint.

The rad circuit is taken off a thermal store. *A Smart pump on the flow and
TRVs all around.

Option 1. *a 3-way domestic diverter valve - on/off not modulating. Drayton
make one with an end switch for around £35-40. *3-way valve on the return.
The compensator sense the return pipe as more stable temps on the return.
If compensator says the return should say, be 35C, and it is above setpoint
the 3-way valve is energised (by the compensator burner mode as it
anti-cycle) and the heating circuit pumps on itself until cooler and below
setpoint of 35C then the valve opens up again taking heat from a thermal
store and allowing cooler water into the bottom of the store. *Either full
on or full off. *Cheap and will work well enough. *Maybe excessive wear on a
domestic 3-way valve motor, but should be OK. *35C water is placed at the
bottom of the thermal store to enhance condensing operation when the boiler
fires up to reheat the store. *Most of the time the water will be below 30C
and the lower store temperature even cooler when DHW is draw off via a plate
heat exchanger returning very cool water (15 to 25C) back to the lower part
of the store. 70 to 80% of the latent heat is recovered when the boiler
return temp is 30C, 50% at 35C.

Option 2. *A 3-way modulating valve, then ensures the return temperature
from the rads is accurate to what the compensator dictates by modulating the
valve. *This ensures most of the time a trickle of cool water into the
bottom of the thermal store, maintaining thermal layering.

Condensing boiler efficiency is greatly raised and comfort conditions
enhanced by a feed-forward control weather compensator. *TRVs trim off
locally.

If the Sauter 3-way valve and actuator are silly prices, I may go with the
3-way domestic diverter valve for ~£40.

Domestic 3-way mid-position valves stall the motor when in mid-position. *I
could look at one of these to stall the motor at any position its travel. *I
haven't looked seriously at this yet.- Hide quoted text -

- Show quoted text -

"Onetap" wrote in message
...
On 25 May, 15:08, "Doctor Drivel" wrote:

Spartan or Sontay; neither of them do Sauter but I don'y know why
you'd want Sauter specifically. Sontay do 3-port rotary shoe Siebe
valves, but they've pasted their name over Siebe's on the on-line data
sheets. Siebe valves are good.


Sauter are very good quality. I have used their kit in the past. I am
using Sauter as a starting point and they appear to be going domestic with
TRV tops.


3-point floating control is the way many commercial mixing valves
work. The option is to have the control electronics in the controller
and have a cheaper valve actuator or have a 0-10V output from the
controller and an expensive actuator with the control electronics
inside it.


Yep


Forget 3-port mid-position valves; Sunvic do Mo-Mo valves that can be
adapted for modulating mixing use; they used to do some relay device
to adapt the standard valve. They've been having reliability issues
with their relays though, allegedly.


I looked at Mo Mo valves, and I like them, but offer no more than cheaper
spring return valve for what I want to do. I didn't know they had an
adapter to convert them to a modulating valve. Not on their site, or did I
miss it? Mo Mo's are cheap on Ebay.


Option 1 is bolleaux.


It isn't. Crude, simple, cheap, domestic kit but workable.


If you want on-off, too hot/too cold control of
the heating why not just do it with a thermostat. Diverter valve = 1
inlet, 2 outlets; I think you'd have to set that up as an injection
valve, but I'm sure you know what you're doing. ;-)


I know exactly what I am doing, and it is being used a crude injection
valve. I am using a weather compensator. A stat is little more than
useless.

The compensator would be set to operate on the spring return 3-way diverter
as if it was a burner - built-in boiler anti-cycling woukld prevent valve
hunting. The return temperature is far more stable than the flow too adding
to stability. TRVs and a Smart pump would reduce excessive flow too. It
will work, but may need a gate valve to balance up.


Option 2; sensible, conventional 3-port mixing. I have one as you
describe with a Siebe mixing valve; very good, if I do say so myself.


That is probably what I will go for, however I like to keep product domestic
if I can as it can confuse dumb plumbers.


Option 3; variable speed injection mixing pump. No valve gland to wear
out. Very reliable, if you know how to do it properly. There's a good
article on the web, but ISTR you derided the author's technical
competence the last time I mentioned him, so I won't offend you by
giving the link here.


Not John Siegenthaler is it? He is bright enough.

I could have a full CH loop an have the compensator switch in a fixed speed
injection pump pumping into the loop when heat is needed, rather than a
3-way diverter valve. The pump uses more power and is bulkier, although you
are right in that it may be more reliable in the long run. Variable speed
injection pumps need a controller, more expense when a simple modulating
valve operated by a weather compensator, and one Smart pump can do the job.


Option 4 as 2 but injection mixing valve. The way I'd go if I ever do
another one.


It offers no more than Option 2. The idea is to get superior comfort
conditions via the weather compensator and the lowest return temperature
from the CH, injected back into the bottom on the thermal store to enhance
condensing. Option one will not create such a stable return temperature but
good enough. Option 2 will create a highly stable return temperature.

Another way is to use a 4 room temperature sensors around the house averaged
and the controller modulating the 3-valve to suit. This may result in very
low temperatures being injected back into the bottom of the store. It is
idiot proof in that all you do is set the setpoint to say 21C (no slope to
set) and the TVRs trim off in the rooms. But more expensive and unwanted
sensors on walls.

Some time back a number of people were installing Sauter valves on
their CH systems. I am looking initially at the BXL valve body and
the
AXCM 117 230v actuator. Anyone find the best/cheapest dealer to buy
from for one off sales?

I bought a number of the motorised actuators a few years ago and
shopped
around for the best price then. That came from Controls Center (i.e.
the specialised controls operation of Wolseley).

I am not sure that Controls Center exists as a separate operation any
longer. Possibly it has been consolidated with Plumb Center.

Do you mean AXCM 117? I can't see such a part number on their site.

Yep.

The AXM series is the normal motorised drive in two versions:

- AXM117F series - fixed positions

- AXM117S series - continuous using a dc control signal.

It looks as though the F series has a 230v model.

Here is the actuator. AXM 117 F200, 230v modulating actuator (230v one
way, 230v the other way) - fixed positions until the controller decides
to nudge it along one way or the other.
http://www.sauterautomation.co.uk/pd...v_en435901.pdf

3-way BXL modulating valve body.
http://www.sauterautomation.co.uk/pd...s_en464072.pdf

Nothing on Plumb Centers site.

OK, so it was AXM. F series.

I had to call Controls Center (as it was), plus a few others. These were
not stock items, but they came back with prices in an hour or so and had
next day availability.

Nothing on any Wolsey sites either. I think the Climate Center will be the
one.

If you're hoping to achieve a form of "analogue" control with an F
series,
the results are not going to be all that good. I tried this as a first
experiment. The problem is that the actuator is essentially dumb. It
has no feedback mechanism and no self calibration.

I don't need feedback from the valve actuator. Just a simple 230v
modulating actuator. It is for a weather compensated rad circuit. The
compensator can switch the boiler burner (with in-built anti-cycle
control)
or pulse a modulating valve one way or the other + or -. No feedback from
valve is needed as the valve position will be wherever it is positioned to
maintain setpoint.

The rad circuit is taken off a thermal store. A Smart pump on the flow and
TRVs all around.

Option 1. a 3-way domestic diverter valve - on/off not modulating. Drayton
make one with an end switch for around £35-40. 3-way valve on the return.
The compensator sense the return pipe as more stable temps on the return.
If compensator says the return should say, be 35C, and it is above
setpoint
the 3-way valve is energised (by the compensator burner mode as it
anti-cycle) and the heating circuit pumps on itself until cooler and below
setpoint of 35C then the valve opens up again taking heat from a thermal
store and allowing cooler water into the bottom of the store. Either full
on or full off. Cheap and will work well enough. Maybe excessive wear on a
domestic 3-way valve motor, but should be OK. 35C water is placed at the
bottom of the thermal store to enhance condensing operation when the
boiler
fires up to reheat the store. Most of the time the water will be below 30C
and the lower store temperature even cooler when DHW is draw off via a
plate
heat exchanger returning very cool water (15 to 25C) back to the lower
part
of the store. 70 to 80% of the latent heat is recovered when the boiler
return temp is 30C, 50% at 35C.

Option 2. A 3-way modulating valve, then ensures the return temperature
from the rads is accurate to what the compensator dictates by modulating
the
valve. This ensures most of the time a trickle of cool water into the
bottom of the thermal store, maintaining thermal layering.

Condensing boiler efficiency is greatly raised and comfort conditions
enhanced by a feed-forward control weather compensator. TRVs trim off
locally.

If the Sauter 3-way valve and actuator are silly prices, I may go with the
3-way domestic diverter valve for ~£40.

Domestic 3-way mid-position valves stall the motor when in mid-position. I
could look at one of these to stall the motor at any position its travel.
I
haven't looked seriously at this yet.- Hide quoted text -

- Show quoted text -

"Onetap" wrote in message
...
On 25 May, 15:08, "Doctor Drivel" wrote:

Spartan or Sontay; neither of them do Sauter but I don'y know why
you'd want Sauter specifically. Sontay do 3-port rotary shoe Siebe
valves, but they've pasted their name over Siebe's on the on-line data
sheets. Siebe valves are good.


I looked at the Sontay catalogue and lo-and-behold, some of their valves are
clearly Sauter with their name on. The actuator is £27 and 3-way valve body
£25. 22mm compression kit is extra, plus VAT. So it looks like it is well
affordable and competitive.

On 25 May, 19:21, "Doctor Drivel" wrote:
"Onetap" wrote in message

I looked at the Sontay catalogue and lo-and-behold, some of their valves are
clearly Sauter with their name on. *The actuator is £27 and 3-way valve body
£25. *22mm compression kit is extra, plus VAT. *So it looks like it is well
affordable and competitive.

There you go, Drivel, you've learnt something from me. Strange that
they do that, I can't see an advantage.
I still go for the Siebe.

Option 4 as 2 but injection mixing valve. The way I'd go if I ever do
another one.
It offers no more than Option 2.

No, lad. All the secondary flow passes through a conventional 3-port
mixing valve.

An injection mixing valve (or pump) only handles the primary flow
going into the secondary variable-temperature circuit. If there's a
big difference between Pri & Sec temperatures, the injection mixing
valve will be smaller and cheaper.

The disadvantage is the mixed proportions will remain constant with a
3-port mixing valve, but with injection mixing, by injection valve or
pump, the proportions and flow temperatures changes with the secondary
flow rate, i.e., TRVs modulating.

"Onetap" wrote in message
...
On 25 May, 19:21, "Doctor Drivel" wrote:
"Onetap" wrote in message

I looked at the Sontay catalogue and
lo-and-behold, some of their valves are
clearly Sauter with their name on. The
actuator is £27 and 3-way valve body
£25. 22mm compression kit is extra, plus
VAT. So it looks like it is well
affordable and competitive.

There you go, Drivel, you've learnt something
from me. Strange that they do that, I can't see
an advantage. I still go for the Siebe.


They are smaller, compression ends, cheaper and still do the same job.

Option 4 as 2 but injection mixing valve.
The way I'd go if I ever do another one.
It offers no more than Option 2.

No, lad. All the secondary flow passes
through a conventional 3-port mixing valve.


That is the idea, as mixing on the CH return will give cooler water
returning to the thermal store.


An injection mixing valve (or pump) only
handles the primary flow going into the
secondary variable-temperature circuit.
If there's a big difference between
Pri & Sec temperatures, the injection mixing
valve will be smaller and cheaper.


Injection mixing will not guarantee cooler return temps back to the store,
more than a simple 3-way mixing valve on the variable temp loop - and only
one Smart pump is needed. An injection pump is cheap and will work, and can
be switched by the weather compensator. In this case, a Gledhill
Boilermate, the compensator can switch the pump via the pcb using a volt
free contact in the compensator. The pcb gives anti-cycle control. When
the store is below 60C the CH pump (could now be the injection pump supplied
with the Gledhill) is switched out to give DHW priority and no cool water
through the rads. Put it this way, a variable temp loop with a Smart pump,
TRVs all around can run though a plate heat exchanger - a full loop. The
Gledhill pump can be the other side of the plate in a very short primary
injection loop. The variable temp loop is isolated. This means no sludge
can enter the thermal store. Just the cost of a plate heat X which is around
£80-90.

In a commercial system fitting a smaller injection pump or valve makes
economic sense. In a small domestic system, there is no price advantage.


The disadvantage is the mixed proportions will remain constant with a
3-port mixing valve, but with injection mixing, by injection valve or
pump, the proportions and flow temperatures changes with the secondary
flow rate, i.e., TRVs modulating.


Mixed proportions are the same - the same goes into the store than what
comes out. That rate can vary as a Smart modulating pump and TVRs raise and
lower the rate into the store.

On the primary loop a Smart pump can be fitted with a 2-port modulating
injection valve, modulated by the weather compensator, sensing the return of
the variable temp loop.

In a variable temp loop the idea is to keep it self contained in flow and
temp and control is easy within that loop - as well as design. So, having
heat injection into the loop that does not influence the characteristics of
the loop makes sense. In a small domestic system this does not apply.

My aim is get a low temp back to the store and maintain enough heat in the
loop to heat the house according to the outside temperature.

Wow! John Siegenthaler and the Yanks have just discovered thermal storage.
A newer approach they say.

"Today, the North American hydronics industry is "rediscovering" the
benefits of hydraulic separation combined with traditional header-type
piping applied to multiload/multitemperature systems. (that means a thermal
store) We're also learning this uses less componentry and lower pumping
wattage relative to primary/secondary piping. As hardware and electricity
prices continue to rise, it's likely these newer approaches will soon become
the standard."

http://www.pmengineer.com/SHT/Home/I...at2Fig10Lg.jpg

"Onetap" wrote in message
...

Option 4 as 2 but injection mixing valve. The way I'd go if I ever do
another one.
It offers no more than Option 2.

No, lad. All the secondary flow passes through a conventional 3-port
mixing valve.


BTW, using a thermal store, the store replaces the primary loop and CH loop
is the variable secondary loop. Think of a thermal store as a very thick,
far superior, vertical header - the primary. A 3-port mixing valve acts
just as one would on a commercial primary loop/secondary loop setup.

Understand why the primary loop is there. A thermal store replaces it. A
direct thermal store on a domestic system gives all the advantages of a
commercial system which domestic system do not have to their detriment. One
reason why primary loops came about was to ensure constant flow through
small tubed, fully pumped, high efficient boilers - the old boilers didn't
even need pumps running. Only direct thermal stores ensure this on domestic
systems. A kludge on domestic is a pressure differential valve to ensure
minimal flow through the boiler, which invariably will not be set properly
hindering the boilers longevity and reducing efficiency on condensing
boilers giving a direct return from flow to return raising the return
temperatures to inefficient levels. When the strings in these valves weaken
with time the condensing efficiency of the system lessens as the return is
short cutted from the flow more often.

Using a 3-port mixing valve on the secondary loop return (CH loop on
domestic) to a thermal store will ensure very low return temperatures to the
bottom of the store too.