I will be installing a new shower shortly and was wondering if any of
you had particular recommendations? Any pros and cons to look out for?

The water system provides hot and cold water at mains pressure
(modulating combi). Static water pressure is OK ( 3bar), flow rate up
to about 15l/min is available from the hot supply - although I would
like to use less than that so as to have something left for the rest of
the house.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

"John Rumm" wrote in message
...
I will be installing a new shower shortly and was wondering if any of
you had particular recommendations? Any pros and cons to look out for?

The water system provides hot and cold water at mains pressure
(modulating combi). Static water pressure is OK ( 3bar), flow rate up
to about 15l/min is available from the hot supply - although I would
like to use less than that so as to have something left for the rest of
the house.

The Mira 415 is the one to go for. Dedicated to mains pressure systems. It
is not thermostatic and has an integral pressure balancing valve. The combi
provides the constant temperature, so no need for a thermostat cartridge in
the mixer. It works very well indeed. When you have equal flow and
pressure on both hot and cold you don't need a thermostat (except where
maybe children are about and they could play about). The 415 adjusts the
hot and cold to equal pressure when any fluctuations. The reaction is far
faster than a thermostat. The 415 is also simpler and if the thermostat
cartridge goes it is usually over £100 to replace. Go for the Mira 415.

"John Rumm"

Recommendation for a thermostatic shower?

IMM wrote:

It is not thermostatic

FUPOS !

"Nick Brooks" wrote in message
...

"John Rumm"

Recommendation for a thermostatic shower?

IMM wrote:

It is not thermostatic

Read my post. He doesn't need a thermostatic mixer with a modulating combi.
He needs a pressure balanced mixer. I'm sure all this has gone right over
your head. Read and learn.

"John Rumm" wrote in message
...
I will be installing a new shower shortly and was wondering if any of
you had particular recommendations? Any pros and cons to look out for?

The water system provides hot and cold water at mains pressure
(modulating combi). Static water pressure is OK ( 3bar), flow rate up
to about 15l/min is available from the hot supply - although I would
like to use less than that so as to have something left for the rest of
the house.


--
Cheers,

John.

I've been using a Hansgrohe Ecostat 2001 for about the last 6 weeks or so
and it's excellent. I've also got a Hansgrohe thermostatic mixer/diverter on
the bath which is great too.

I've tried turning on various taps (hot and/or cold) while the shower is
running and the response is very good - unless you knew someone was going to
turn the tap on I doubt you'd even notice really.

I suspect it depends on the exact details of the implementation, though.

Neil

"Nick Brooks" wrote in message
...

"John Rumm"

Recommendation for a thermostatic shower?

IMM wrote:

It is not thermostatic

FUPOS !

What is FUPOS?

IMM wrote:
"Nick Brooks" wrote in message
...

"John Rumm"


Recommendation for a thermostatic shower?

IMM wrote:


It is not thermostatic


Read my post. He doesn't need a thermostatic mixer with a modulating combi.
He needs a pressure balanced mixer. I'm sure all this has gone right over
your head. Read and learn.



you seem to have accidentally snipped the interesting bit of my post -
read it and learn

IMM wrote:
"Nick Brooks" wrote in message
...

"John Rumm"


Recommendation for a thermostatic shower?

IMM wrote:


It is not thermostatic

FUPOS !


What is FUPOS?



you are !

On Wed, 26 May 2004 15:15:44 +0100, John Rumm
wrote:

I will be installing a new shower shortly and was wondering if any of
you had particular recommendations? Any pros and cons to look out for?

The water system provides hot and cold water at mains pressure
(modulating combi). Static water pressure is OK ( 3bar), flow rate up
to about 15l/min is available from the hot supply - although I would
like to use less than that so as to have something left for the rest of
the house.

I would go for a good quality thermostatic valve like a Mira, Grohe or
Aqualisa.

This will take out any temperature variations with different flows
around the house due to taps being turned on.

You can easily control flow by virtue of using a smaller diameter hose
or even restrictors if need be.


..andy

To email, substitute .nospam with .gl

"Nick Brooks" wrote in message
...
IMM wrote:
"Nick Brooks" wrote in message
...

"John Rumm"


Recommendation for a thermostatic shower?

IMM wrote:


It is not thermostatic

FUPOS !


What is FUPOS?

you are !

You don't say........

"Andy Hall" wrote in message
...
On Wed, 26 May 2004 15:15:44 +0100, John Rumm
wrote:

I will be installing a new shower shortly and was wondering if any of
you had particular recommendations? Any pros and cons to look out for?

The water system provides hot and cold water at mains pressure
(modulating combi). Static water pressure is OK ( 3bar), flow rate up
to about 15l/min is available from the hot supply - although I would
like to use less than that so as to have something left for the rest of
the house.

I would go for a good quality thermostatic valve like a Mira, Grohe or
Aqualisa.

This will take out any temperature variations with different flows
around the house due to taps being turned on.

You can easily control flow by virtue of using a smaller diameter hose
or even restrictors if need be.

Or use a pressure balancing valve or a dedicated combi/main pressure mixer,
like the Mira 415.

"John Rumm" wrote in message
...
I will be installing a new shower shortly and was wondering if any of
you had particular recommendations? Any pros and cons to look out for?

The water system provides hot and cold water at mains pressure
(modulating combi). Static water pressure is OK ( 3bar), flow rate up
to about 15l/min is available from the hot supply - although I would
like to use less than that so as to have something left for the rest of
the house.

Most quality mixers come with a flow restrictor between the hose and the
mixer body. This is usually removable for full flow on lower pressure
systems.

On Wed, 26 May 2004 16:01:45 +0100, "IMM" wrote:




Or use a pressure balancing valve or a dedicated combi/main pressure mixer,
like the Mira 415.

Hmm. We seem to be going down the want/need track again....


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Wed, 26 May 2004 16:01:45 +0100, "IMM" wrote:

Or use a pressure balancing valve or a dedicated combi/main pressure
mixer,
like the Mira 415.

Hmm. We seem to be going down the want/need track again....

There are better solutions than others. This is a better solution.

"Andy Hall" wrote in message
...
On Wed, 26 May 2004 15:15:44 +0100, John Rumm
wrote:

I will be installing a new shower shortly and was wondering if any of
you had particular recommendations? Any pros and cons to look out for?

The water system provides hot and cold water at mains pressure
(modulating combi). Static water pressure is OK ( 3bar), flow rate up
to about 15l/min is available from the hot supply - although I would
like to use less than that so as to have something left for the rest of
the house.

I would go for a good quality thermostatic valve like a Mira, Grohe or
Aqualisa.

This will take out any temperature variations with different flows
around the house due to taps being turned on.

You can easily control flow by virtue of using a smaller diameter hose
or even restrictors if need be.


.andy

We have an Aqualisa "Aquavalve 609" thermostatic mixer in one bathroom and a
Mira "New Excel" in the other. These are both run from a large (Eco Hometec)
fully modulating condensing combi.

The Mira is FAR better than the Aqualisa at regulating the temperature when
other taps or toilets start taking water. The Aqualisa typically runs very
cool for up to I'd guess around 15-20 seconds, whereas the Mira almost
instantly adjusts so you can hardly notice a temperature drop.

This may be due to something in the installation, but I'd be very surprised
as the HW and CW supplies to both showers are taken separately from the
boiler and CW feed down dedicated 22mm pipes that are not teed to anything
else (as per earlier recommendations a while ago by "IMM" or the very
similar "Adam" who mysteriously disappeared about the time that IMM appeared
in this NG).

Regards,
Simon.

"John Rumm" wrote in message
...
I will be installing a new shower shortly and was wondering if any of
you had particular recommendations? Any pros and cons to look out for?

The water system provides hot and cold water at mains pressure
(modulating combi). Static water pressure is OK ( 3bar), flow rate up
to about 15l/min is available from the hot supply - although I would
like to use less than that so as to have something left for the rest of
the house.


--
Cheers,

John.

You could try the Grohetherm 2000 or 3000, they are thermostatic and allow
you to adjust the flow rate. there is a little button on the knob which
stops at about 8 lpm, press it in and you can increase upto 18 lmp (
depending on your supply. Extremely well made and reliable.

Joe

"Simon Stroud" wrote in message
...

"Andy Hall" wrote in message
...
On Wed, 26 May 2004 15:15:44 +0100, John Rumm
wrote:

I will be installing a new shower shortly and was wondering if any of
you had particular recommendations? Any pros and cons to look out for?

The water system provides hot and cold water at mains pressure
(modulating combi). Static water pressure is OK ( 3bar), flow rate up
to about 15l/min is available from the hot supply - although I would
like to use less than that so as to have something left for the rest of
the house.

I would go for a good quality thermostatic valve like a Mira, Grohe or
Aqualisa.

This will take out any temperature variations with different flows
around the house due to taps being turned on.

You can easily control flow by virtue of using a smaller diameter hose
or even restrictors if need be.


.andy

We have an Aqualisa "Aquavalve 609" thermostatic mixer in one bathroom and
a
Mira "New Excel" in the other. These are both run from a large (Eco
Hometec)
fully modulating condensing combi.

The Mira is FAR better than the Aqualisa at regulating the temperature
when
other taps or toilets start taking water. The Aqualisa typically runs very
cool for up to I'd guess around 15-20 seconds, whereas the Mira almost
instantly adjusts so you can hardly notice a temperature drop.

The Excel has intregrated flow control. This reacts quite fast.

This may be due to something in the installation, but I'd be very
surprised
as the HW and CW supplies to both showers are taken separately from the
boiler and CW feed down dedicated 22mm pipes that are not teed to anything
else (as per earlier recommendations a while ago by "IMM" or the very
similar "Adam" who mysteriously disappeared about the time that IMM
appeared
in this NG).

Regards,
Simon.

IMM wrote:

The Mira 415 is the one to go for. Dedicated to mains pressure systems. It
is not thermostatic and has an integral pressure balancing valve. The combi
provides the constant temperature, so no need for a thermostat cartridge in

Why do you say the combi provides a constant temperature? Even
modulating combis with a maximum water temp thermostats will vary
temperature in inverse proportion to requested flow rate (the max temp
rising up to the cap set by the stat at low flow rates)

So if you have the boiler stat set to limit at 60 degrees and draw off 8
l/min then the temp will be 60 deg. If the dishwasher then decides to
take the total hot water flow rate to 15 l/min the temperature will have
to fall. How does the pressure balance cope with that?

(I can see how it would work well on a unvented HW cylinder for example,
because the HW flow rate would not affect the temperature of the water)


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

"John Rumm" wrote in message
...
IMM wrote:

The Mira 415 is the one to go for. Dedicated
to mains pressure systems. It is not thermostatic
and has an integral pressure balancing valve. The combi
provides the constant temperature, so no need for a
thermostat cartridge in

Why do you say the combi provides a
constant temperature?

It has an output thermostat attached that modulates the burner to suit.

Even modulating combis with a maximum
water temp thermostats will vary
temperature in inverse proportion to requested
flow rate (the max temp rising up to the cap
set by the stat at low flow rates)

The temperature stability is not that precise though, but ballpark enough.

So if you have the boiler stat set to limit
at 60 degrees and draw off 8
l/min then the temp will be 60 deg.
If the dishwasher then decides to
take the total hot water flow rate to
15 l/min the temperature will have
to fall.

It will not fall. The burner modulates up to cope. Although some combi's are
better than others in maintaining outlet temperature. Generally the more
expensive the better the control.

How does the pressure balance cope with that?

If you are drawing 8 l/min and then taps are turned on to ramp up to 14
l/min, then the pressure in the hot line will drop. The balancing valve will
drop the cold inlet to the mixer to the same as the hot, preventing
excessive cold being drawn off through the mixer, keeping the temperature
stable.

(I can see how it would work well on
a unvented HW cylinder for example,
because the HW flow rate would not
affect the temperature of the water)

Yes, an unvented cylinder is better in this respect. But, some thermostatic
blending valves will be mandatory on new installations. So, the speed of
reaction of the blending valve may perform like a combi. When the blenders
are mandatory, I would take the hot shower supply direct from cylinder
before any blending valve. Although to conform to the future regs you have
to install something like an Excel mixer with temperature limit setting.

"John Rumm" wrote in message
...
I will be installing a new shower shortly and was wondering if any of
you had particular recommendations? Any pros and cons to look out for?

The water system provides hot and cold water at mains pressure
(modulating combi). Static water pressure is OK ( 3bar), flow rate up
to about 15l/min is available from the hot supply - although I would
like to use less than that so as to have something left for the rest of
the house.

We used an Aqualisa in exactly the same situation and it worked beautifully.
Even when taps were turned on around the house and the flow reduced to not
much more than a dribble at least the temperature remained constant.

Rgds

Andy R

"Neil Jones" wrote in message

I've been using a Hansgrohe Ecostat 2001 for about the last 6 weeks or so
and it's excellent. I've also got a Hansgrohe thermostatic mixer/diverter on
the bath which is great too.

We had a Hansgrohe thermostatic shower though not quite the same
design. Far cheaper than anything else we looked at and worked
perfectly with our Combi and reacted quickly enough when the toilet
was flushed.

Maybe not the only or optimum solution but we never had any issues
with it.

AJ

"John Rumm" wrote in message
...
IMM wrote:

The Mira 415 is the one to go for. Dedicated to mains pressure systems.
It
is not thermostatic and has an integral pressure balancing valve. The
combi
provides the constant temperature, so no need for a thermostat cartridge
in

Why do you say the combi provides a constant temperature? Even
modulating combis with a maximum water temp thermostats will vary
temperature in inverse proportion to requested flow rate (the max temp
rising up to the cap set by the stat at low flow rates)

So if you have the boiler stat set to limit at 60 degrees and draw off 8
l/min then the temp will be 60 deg. If the dishwasher then decides to
take the total hot water flow rate to 15 l/min the temperature will have
to fall. How does the pressure balance cope with that?

(I can see how it would work well on a unvented HW cylinder for example,
because the HW flow rate would not affect the temperature of the water)

Here is a cut & paste from Plumbworld on a stand alone pressure equalising
valve:

"
- Automatically equalises hot and cold water pressure by dynamically
adjusting the higher water pressure to balance with the lower
- Can turn a manual shower into a shower that doesn't suffer temperature
fluctuations
- Provides - stable water temperature
- Pressure range 3psi to 150psi
- Eliminates risk of scalding
- Cost effective and easy to install
- Cast brass body, Premium nickel finish
- 15mm compression connections
- Can be used on low and "mains" pressure hot water systems
- Ideal for - Rest Homes, Hostels, Hotels, Private Homes, Sports Clubs,
Hospitals
- Can turn a manual shower into a shower that doesn't suffer temperature
fluctuations
"
http://www.plumbworld.co.uk/344-0000

BES sell what looks to be the same valve (made in NZ) at the same price.

A poor performing thermostatic valve or a standard mixer can really perform
after fitting one of these on the supply. The Mira 415 has one built-in.
It may be cost effective to buy a standard non-thermostatic mixer and one of
these @ £35 plus VAT, if space is available. Then it is a matter of only
replacing the valve if it goes wrong rather than a whole expensive mixer.

If you are drawing 8 l/min and then taps are turned on to ramp up to 14
l/min, then the pressure in the hot line will drop. The balancing valve
will
drop the cold inlet to the mixer to the same as the hot, preventing
excessive cold being drawn off through the mixer, keeping the temperature
stable.

You clearly live in a doll's house. When I turn on a tap, I get 30 l/min.
This would lead to a drop in temperature. Furthermore, the combi is likely
to be set to 60C output to allow dishwashing. Therefore, even on quite
moderate hot water flow rates, you'll be in the temperature unstable range.

Whilst the Mira is undoubtedly a high quality product, it suffers from a
vital flaw is that it doesn't have separate flow and temperature controls.
My mother uses the cheap thermostatic one downstairs as the Mira is too
difficult to set the temperature of and can't have the flow turned down.

I agree with the first part (but don't mind the high flow) and like to leave
the temperature setting alone and use the flow control as an on/off, not
experimenting to get the right temperature every time.

Christian.

"Christian McArdle" wrote in message
. net...
If you are drawing 8 l/min and then taps are turned on to ramp up to 14
l/min, then the pressure in the hot line will drop. The balancing valve
will
drop the cold inlet to the mixer to the same as the hot, preventing
excessive cold being drawn off through the mixer, keeping the
temperature
stable.

You clearly live in a doll's house.

You clearly know nothing of this subject. We shall continue....

When I turn on a tap, I get 30 l/min.
This would lead to a drop in temperature.

You have a heat bank with a thermostatic blending valve controlling DHW
temperature, not a combi.

Furthermore, the combi is likely
to be set to 60C output to allow dishwashing.
Therefore, even on quite moderate hot water
flow rates, you'll be in the temperature unstable range.

What are you on about? Oh, don't bother.

Whilst the Mira is undoubtedly a high quality
product, it suffers from a vital flaw is that it
doesn't have separate flow and temperature controls.

The 415 only has manual flow control and auto pressure balancing. No auto
temp control to maintain a setpoint temperature, only manual by mixing hot
and cold water to user requirements.

The Excel mixer controls the flow through the mixer and a fast acting
temperature control, one reason why Simon Stroud experiences virtually no
fluctuations.

My mother uses the cheap thermostatic one
downstairs as the Mira is too difficult to set
the temperature of and can't have the flow turned down.

I agree with the first part (but don't mind the high flow) and like to
leave
the temperature setting alone and use the flow control as an on/off, not
experimenting to get the right temperature every time.

Christian.

"Christian McArdle" wrote in message
. net...

My mother uses the cheap thermostatic one downstairs as the Mira is too
difficult to set the temperature of and can't have the flow turned down.

You can regulate the flow on an Mira shower. What are you on about?

You have a heat bank with a thermostatic blending valve controlling DHW
temperature, not a combi.

Yes, but you are proposing that turning on a hot tap would produce only 6
lpm at the tap. You'd got hot water faster by warming cold water between
your buttocks.

Furthermore, the combi is likely
to be set to 60C output to allow dishwashing.
Therefore, even on quite moderate hot water
flow rates, you'll be in the temperature unstable range.

What are you on about? Oh, don't bother.

I'm saying that with the combi set for 60C, the 15 lpm spec of the boiler
(at 40C) equates to around 9.5 litres per minute. Draw any more than this
and the temperature will drop, requiring adjustment at the mixer.

The 415 only has manual flow control and auto pressure balancing. No auto
temp control to maintain a setpoint temperature, only manual by mixing hot
and cold water to user requirements.

I don't dispute that pressure balancing is an essential feature. I would not
buy a shower mixer without that feature. However, it is quite possible
(indeed, is normal) to buy a shower mixer both pressure balanced (for speed
of correction) and thermostatically controlled (for temperature
pre-selection and adjusting to varying water supply temperatures).

Christian.

You can regulate the flow on an Mira shower. What are you on about?

We might be talking about different models. She has a single control.
Anti-clockwise is off. Then rotating clockwise slightly turns it on. Turning
it further adjusts the temperature. It said Mira 415 on the box, but there
might be multiple versions of this mixer.

Christian.

You can regulate the flow on an Mira shower. What are you on about?

We might be talking about different models. She has a single control.

OK. Reading the official Mira 415 instructions:

"Initial anticlockwise movement turns the water on at full flow of cold
water, further
anticlockwise movement increases the temperature. The flow rate is
determined by
the supply pressures at the shower control inlets, or by the effective
output power
of the heater appliance. Flow rates for gas heater appliances can vary
typically
between 8 l/min (winter) and 15 l/min (summer)."

http://www.mirashowers.com/onlinecat...df/p3740_2.pdf

OK, I got clockwise/anticlockwise mixed up. Would you like to explain why
you think a Mira 415 has a flow control?

OTOH, I can't see how the flow rate would be determined by the heater output
without some manually adjusted throttling, although the instructions do say
something about having an automatic device in the combi to throttle when the
flow reduces. Of course, most combis don't have this feature. They just run
cold.

Christian.

"Christian McArdle" wrote in message
. net...
You have a heat bank with a thermostatic blending valve controlling DHW
temperature, not a combi.

Yes, but you are proposing that turning on a hot tap would produce only 6
lpm at the tap.

Where did you get that from?

Furthermore, the combi is likely
to be set to 60C output to allow dishwashing.
Therefore, even on quite moderate hot water
flow rates, you'll be in the temperature unstable range.

What are you on about? Oh, don't bother.

I'm saying that with the combi set for 60C,
the 15 lpm spec of the boiler (at 40C) equates
to around 9.5 litres per minute. Draw any more
than this and the temperature will drop,
requiring adjustment at the mixer.

If you draw large amounts of water at other taps the temp will down. Turn
all your hot taps on your heat bank suffer the same.

The 415 only has manual flow control
and auto pressure balancing. No auto
temp control to maintain a setpoint temperature,
only manual by mixing hot
and cold water to user requirements.

I don't dispute that pressure balancing is an essential feature. I would
not
buy a shower mixer without that feature. However, it is quite possible
(indeed, is normal) to buy a shower mixer both pressure balanced (for
speed
of correction) and thermostatically controlled (for temperature
pre-selection and adjusting to varying water supply temperatures).

It is not normal to buy a mixer with both functions at all. Most buy only
thermostatic mixers only.

"Christian McArdle" wrote in message
. net...
You can regulate the flow on an Mira shower. What are you on about?

We might be talking about different models. She has a single control.
Anti-clockwise is off. Then rotating clockwise slightly turns it on.
Turning
it further adjusts the temperature. It said Mira 415 on the box, but there
might be multiple versions of this mixer.

The 415 has limited flow control. The idea is to get a minimum flow so that
pressure valves can fully open. ON many combi's this is not the case and
just a trickle of water will be enough to fire the burner.

"Christian McArdle" wrote in message
. net...
You can regulate the flow on an Mira shower. What are you on about?

We might be talking about different models. She has a single control.

OK. Reading the official Mira 415 instructions:

"Initial anticlockwise movement turns the water on at full flow of cold
water, further
anticlockwise movement increases the temperature. The flow rate is
determined by
the supply pressures at the shower control inlets, or by the effective
output power
of the heater appliance. Flow rates for gas heater appliances can vary
typically
between 8 l/min (winter) and 15 l/min (summer)."

http://www.mirashowers.com/onlinecat...df/p3740_2.pdf

OK, I got clockwise/anticlockwise mixed up. Would you like to explain why
you think a Mira 415 has a flow control?

The older models certainly did have a good range. The newer versions are
obviously limited.

OTOH, I can't see how the flow rate would
be determined by the heater output
without some manually adjusted throttling,

If the pressure/flow is pretyty equal on cold and hot then the appliance can
ramp it up and down.

although the instructions do say
something about having an automatic device
in the combi to throttle when the
flow reduces. Of course, most combis don't
have this feature. They just run cold.

The up market versions do. If this is a problem then flow controls valves
can be inserted in to the combi inlet and cold to the shower. Set to 15
l/min, the combi maximum flowrate, then you will never run cold.

On Wed, 26 May 2004 21:39:47 +0200, "Joe" (@((I.(( wrote:


"John Rumm" wrote in message
.. .
I will be installing a new shower shortly and was wondering if any of
you had particular recommendations? Any pros and cons to look out for?

The water system provides hot and cold water at mains pressure
(modulating combi). Static water pressure is OK ( 3bar), flow rate up
to about 15l/min is available from the hot supply - although I would
like to use less than that so as to have something left for the rest of
the house.


--
Cheers,

John.

You could try the Grohetherm 2000 or 3000, they are thermostatic and allow
you to adjust the flow rate. there is a little button on the knob which
stops at about 8 lpm, press it in and you can increase upto 18 lmp (
depending on your supply. Extremely well made and reliable.

Joe

One point not covered that I have noticed is to consider if anyone has
any problems with particular controls. In this household one person
has arthritic hands and cannot cope with slippery knobs on taps or
shower controls. Some showers have levers available, possibly as an
option, for flow and temperature controls or a combined lever for
both.
I never thought about such matters when I was young but it
matters now to some of us.

The 415 has limited flow control.

It has no flow control beyond on/off. Once turned on, it will pass as much
water as will fit through the pipework, valve and shower head.

Christian.

It is not normal to buy a mixer with both functions at all. Most buy only
thermostatic mixers only.

Whatever you say.

I have bought 2 cheap thermostatic mixer showers in the last 3 years. Both
had pressure balancing operation as well as thermostatic. Each was under 100
quid. In each case, they were the cheapest thermostatic mixer valves sold by
the shop.

Christian.

The older models certainly did have a good range. The newer versions are
obviously limited.

OK, then. How did you set the flow rate and temperature? Where was this
mythical flow rate setting knob?

Christian.

"Christian McArdle" wrote in message
. net...
The older models certainly did have a good range. The newer versions
are
obviously limited.

OK, then. How did you set the flow rate and temperature?

You turned the knob.

On Fri, 28 May 2004 23:52:59 +0100, "IMM" wrote:


"Christian McArdle" wrote in message
.net...
The older models certainly did have a good range. The newer versions
are
obviously limited.

OK, then. How did you set the flow rate and temperature?

You turned the knob.


On your side?


..andy

To email, substitute .nospam with .gl

In article , Andy Hall
writes
On Fri, 28 May 2004 23:52:59 +0100, "IMM" wrote:


"Christian McArdle" wrote in message
x.net...
The older models certainly did have a good range. The newer versions
are
obviously limited.

OK, then. How did you set the flow rate and temperature?

You turned the knob.


On your side?


I thought turning the knob on your side was for opening the door in your
pyjamas.
--
Peter

Ying tong iddle-i po!

On Sat, 29 May 2004 00:14:25 +0100, Peter Twydell
wrote:

In article , Andy Hall
writes
On Fri, 28 May 2004 23:52:59 +0100, "IMM" wrote:


"Christian McArdle" wrote in message
ex.net...
The older models certainly did have a good range. The newer versions
are
obviously limited.

OK, then. How did you set the flow rate and temperature?

You turned the knob.


On your side?


I thought turning the knob on your side was for opening the door in your
pyjamas.

I haven't got a knob on my side......


..andy

To email, substitute .nospam with .gl

IMM wrote:

Why do you say the combi provides a
constant temperature?


It has an output thermostat attached that modulates the burner to suit.

IME the stat will prevent the boiler exceeding the maximum selected
temperature. However, there is nothing it can do once the maximum heat
output of the boiler is already demanded. For DHW at 60 degrees this
will be at quite modest flow rates even on high output combis. The
result is the DHW temp will fall (and by a large margin). ISTM that a
thermostatic mixer will be able to take account of a large swing in
output temperature from say 60 down to 45 by varing the cold input from
"some" to "practically none" - I can't see how just balancing the
pressure alone can achieve the same result.

How does the pressure balance cope with that?


If you are drawing 8 l/min and then taps are turned on to ramp up to 14
l/min, then the pressure in the hot line will drop. The balancing valve will
drop the cold inlet to the mixer to the same as the hot, preventing
excessive cold being drawn off through the mixer, keeping the temperature
stable.

but that does not take account of the fall in the DHW temperature that
accompanies the pressure fall - if you are balancing only on pressure
you must assume a constant (ish) temperature supply of HW.


--
Cheers,

John.

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