On Tue, 13 Sep 2005 01:15:12 +0100, Peter wrote:

Many people install based on price not performance. So loads of people
go for 24kW models. Lots of these will be old 70% efficient jobs that
can only throw 18kW of heat at the water.

Is this what the power rating is? So a 24kW model *uses* 24kW but does
not *provide* 24kW of power?

Generally the older and less powerful boilers are quoted in what they do
(output). Whilst the newer and more powerful models are listed by what
they eat (input).

Read the small print in your catalogues.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html

John Rumm wrote:
Guess he has to do something while

You piece of filth, Rumm. Why post stuff like that? So
we have to put up not only with Drivel, but juvenile
louts too? Wash your mouth out with Wright's soap,
and say sorry (to the group - not Drivel).

Chris Bacon wrote:

and say sorry (to the group - not Drivel).

I will say sorry to Dave for the implied suggestion...

Now stop being such and old woman.


--
Cheers,

John.

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

Doctor Drivel wrote:
"Fitz" wrote in message
oups.com...

Dave Fawthrop wrote:
There is a disagreement in another thread as to the adequacy of hot
water
supplies from combi boilers.

There must be lots of people here with them, so will these people ple=
ase
answer the question
"Are you satisfied with hot water from a combi boiler, without extra
storage".

Cor, what a lof of fuss some people have made about answering this...

I've lived in 9 different premises in my 30-odd years on this planet
and obviously visited friends relatives, stayed in hotels blah, blah in
countless others.

Of the 9:
4 were stored hot water systems.
1 was a university halls of residence with a giant site wide heating
system
4 were combi boilers.

Obviously the best for everything was the halls of residence. Never
ending hot water at a million liters a minute (approximately ;-)

Of the combis only my most recent has given truly acceptable
performance. It's a new Worcester Bosch Greenstar 35kw. We only have
a single bathroom and use a dishwasher for 95% of dishes. It provides
a very nice shower admittedly at the lower end of acceptable pressure
range. The bath is filled within about 10 minutes which I gather some
people think is a long time. Personally I never have 'emergency' baths
and can easily kill 10 minutes. It does a very, very good job of
heating the house and with the trv's on most rads we have a constant
temperature throughout the house. I think this was actually more luck
than judgement, but the modulating ability of the boiler does keep the
flow ticking over at a low temp in milder times.

The other 3 combis were smaller and older and performance varied, from
utterly unnaceptable to liveable with. A friend of mine is selling a
house where the combi will take an hour to fill the bath. I didn't
believe it until he showed me the flow he was getting. I can't help
but think something is wrong with it.

Of the stored systems all were open systems so relying on gravity for
the pressure. The only one to provide a good shower was boosted by a
noisy pump. The tank was quite small and would run out if we had 4
people to get through the shower.

If I had more bathrooms than I do now I'd like to fit a sealed system
with a stored water capability, but I'll do this as part of an
extension if I ever have one.

So there you go. I do think combi's have there uses but I'm aware of
the limitations as well and would look to a different solution in more
demanding cirumstances.

You have made an assessment on limited experience of combis. Most of this
thread is utter ********

The highest flowrate are floor mounted combis: W-Bosch Highflow 440, Voke=
ra,
Potterton Powermax, Ideal Istor, Viessmann 333, ACV Heatmaster (Stainless
steel hybrid of thermal store, serving the CH, and unvented cylinder and
heat exchanger running through the store, which will deliver 38 litres/min
for 10 mins then drop to 15 litres/min). Beat that!! "never" runs out of
hot water. Hard to on any system.

Welcome back IMM. The high flows rates of the ACV attracted me. I
looked up the ACV (I have never heard of it) and it looks a substantial
piece of combi with a stainless steel tank in tank, which is a cylinder
immersed completely inside another cylinder. The price is about =A32,300
with quality to boot. That sounds expensive, yet if you buy a stainless
steel tank in tank, or just a standard stainless steel unvented
cylinder and a quality condensing boiler of 35kW, after buying all the
controls, you end up paying more than =A32.3 K. It is one of the most
efficient boilers in sedbuk and the dealer said they have good backup.
I am about to order a Rinnai for two Triton tower showers and a boiler
for the CH. I may reconsider and look at the ACV more depth. It is
slightly bigger than a Powermax about 600mm square, and 5.5 foot high,
making it easy enough to go in lofts. The Rinnai never runs out hot
water so can deliver the flow and no time limit to showers.

I'll let people know what I do and how the Rinnai performs if and when
it is installed. I looked at the ACV manual and can't figure out in
detail how it works. Any ideas? Do I have to be BBA approved to fit it?

Wall mounted models with v good flowrates are the Alpha cd50 and
ECO-Hometec.

Want instant water at the taps? Some have a small vessel inside, some ha=
ve
a "keep warm" heat exchanger, and all can have a secondary circulation lo=
op.
Dead leg pipe is a problem with "all" systems,

As many of the idiots on this thread spurted forth, combis are full of si=
lly
old wives tales, which are untrue, pasing off old crap models as the norm.
Want two baths to be filled simultaneously? One can do it. Just choose =
the
model.

Then there is the high flowrate Japanese multi-points which belt out the
flowrates.

I read back on some of the threads. I believe Plowman is shagging Mary. =
Is
that true?

"Chris Bacon" wrote in message
...
John Rumm wrote:
Guess he has to do something while

You piece of filth, Rumm. Why post stuff like that? So
we have to put up not only with Drivel, but juvenile
louts too? Wash your mouth out with Wright's soap,
and say sorry (to the group - not Drivel).

The Rumm bugger neds to boil his head.

In article ws.net,
Doctor Drivel wrote:
"Yes and no" answers seem to be so last week at the moment. 8-;

Just wait till Drivel comes back from holiday. ;-)

I am and I believe you are shagging Mary.

Sad the holiday didn't fix your brain.

--
*The more people I meet, the more I like my dog.

Dave Plowman London SW
To e-mail, change noise into sound.

In article ws.net,
Doctor Drivel wrote:
As many of the idiots on this thread spurted forth, combis are full of
silly old wives tales, which are untrue, pasing off old crap models as
the norm. Want two baths to be filled simultaneously? One can do it.
Just choose the model.

Some of us are used to 25 litres plus per minute of piping hot water to
fill our baths regardless of external conditions.

I'd be interested in your domestic combi on a domestic gas supply that can
do 50 litres plus of water at 60C regardless of external conditions?

But I'll not hold my breath.

--
*A nest isn't empty until all their stuff is out of the attic

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
John Rumm wrote:
Chris Bacon wrote:

and say sorry (to the group - not Drivel).

I will say sorry to Dave for the implied suggestion...

Don't ever worry about me. I've been insulted by experts. ;-)

--
*Why are they called apartments, when they're all stuck together? *

Dave Plowman London SW
To e-mail, change noise into sound.

In article .com,
wrote:
Welcome back IMM.

The sock puppet returns...

--
*Why doesn't glue stick to the inside of the bottle?

Dave Plowman London SW
To e-mail, change noise into sound.

On Tue, 13 Sep 2005 20:08:33 +0100, "Dave Plowman (News)"
wrote:

| In article ws.net,
| Doctor Drivel wrote:
| As many of the idiots on this thread spurted forth, combis are full of
| silly old wives tales, which are untrue, pasing off old crap models as
| the norm. Want two baths to be filled simultaneously? One can do it.
| Just choose the model.
|
| Some of us are used to 25 litres plus per minute of piping hot water to
| fill our baths regardless of external conditions.

Maybe I have seen that a few times in hotels, never at home. I find 8l/m,
measured, perfectly satisfactory. Fills a bath in about 7 mins, as would
the proposed combi. I have set my conventional system to simulate the
proposed combi and there is little difference between what I have now and
the proposed combi. I have no idea where people get 15 mins for a bath
from, maybe it is an Urban Legend.
--
Dave Fawthrop dave hyphenologist co uk
"Intelligent Design?" my knees say *not*.
"Intelligent Design?" my back says *not*.

In message , Andy Hall
writes
On Tue, 13 Sep 2005 00:03:49 +0100, "Doctor Drivel"
wrote:



As many of the idiots on this thread spurted forth, combis are full of silly
old wives tales, which are untrue, pasing off old crap models as the norm.


Gosh, and here was me thinking that they had a burner and a heat
exchanger. What do the old wives tales do? Presumably they talk
up the performance like you do.....


How was Eyebyeza?

Nah I reckon it was one of those "clinics" in Bangkok

Just not the man he used to be .... so to speak

--
geoff

On Tue, 13 Sep 2005 20:03:03 +0100, "Dave Plowman (News)"
scrawled:

In article ws.net,
Doctor Drivel wrote:
"Yes and no" answers seem to be so last week at the moment. 8-;

Just wait till Drivel comes back from holiday. ;-)

I am and I believe you are shagging Mary.

Sad the holiday didn't fix your brain.

Not as sad as the fact that his plane didn't crash.
--
Stuart @ SJW Electrical

Please Reply to group

On Tue, 13 Sep 2005 20:54:06 +0100, Dave Fawthrop
wrote:

On Tue, 13 Sep 2005 20:08:33 +0100, "Dave Plowman (News)"
wrote:

| In article ws.net,
| Doctor Drivel wrote:
| As many of the idiots on this thread spurted forth, combis are full of
| silly old wives tales, which are untrue, pasing off old crap models as
| the norm. Want two baths to be filled simultaneously? One can do it.
| Just choose the model.
|
| Some of us are used to 25 litres plus per minute of piping hot water to
| fill our baths regardless of external conditions.

Maybe I have seen that a few times in hotels, never at home. I find 8l/m,
measured, perfectly satisfactory. Fills a bath in about 7 mins, as would
the proposed combi.

56 litres? That would bearly be enough to paddle in.

I have set my conventional system to simulate the
proposed combi and there is little difference between what I have now and
the proposed combi. I have no idea where people get 15 mins for a bath
from, maybe it is an Urban Legend.

Not really - just simple arithmetic for what is required for a
standard sized bath as opposed to a bidet.


--

..andy

To email, substitute .nospam with .gl

In article , Dave Fawthrop
writes
On Tue, 13 Sep 2005 20:08:33 +0100, "Dave Plowman (News)"
wrote:

| In article ws.net,
| Doctor Drivel wrote:
| As many of the idiots on this thread spurted forth, combis are full of
| silly old wives tales, which are untrue, pasing off old crap models as
| the norm. Want two baths to be filled simultaneously? One can do it.
| Just choose the model.
|
| Some of us are used to 25 litres plus per minute of piping hot water to
| fill our baths regardless of external conditions.

Maybe I have seen that a few times in hotels, never at home. I find 8l/m,
measured, perfectly satisfactory. Fills a bath in about 7 mins, as would
the proposed combi. I have set my conventional system to simulate the
proposed combi and there is little difference between what I have now and
the proposed combi. I have no idea where people get 15 mins for a bath
from, maybe it is an Urban Legend.

What do you do, just wash your feet? or are you talking about a baby
bath? 56 litres is about half of a small bath so its easy to see where
15 mins comes from, its the time a 8l/m combi takes to fill up a small
bath of 100l. My bath takes 180l, I'll leave that calculation to you
--
David

On Wed, 14 Sep 2005 08:38:17 +0100, David
wrote:

| In article , Dave Fawthrop
| writes
| On Tue, 13 Sep 2005 20:08:33 +0100, "Dave Plowman (News)"
| wrote:
|
| | In article ws.net,
| | Doctor Drivel wrote:
| | As many of the idiots on this thread spurted forth, combis are full of
| | silly old wives tales, which are untrue, pasing off old crap models as
| | the norm. Want two baths to be filled simultaneously? One can do it.
| | Just choose the model.
| |
| | Some of us are used to 25 litres plus per minute of piping hot water to
| | fill our baths regardless of external conditions.
|
| Maybe I have seen that a few times in hotels, never at home. I find 8l/m,
| measured, perfectly satisfactory. Fills a bath in about 7 mins, as would
| the proposed combi. I have set my conventional system to simulate the
| proposed combi and there is little difference between what I have now and
| the proposed combi. I have no idea where people get 15 mins for a bath
| from, maybe it is an Urban Legend.
|
| What do you do, just wash your feet? or are you talking about a baby
| bath? 56 litres is about half of a small bath so its easy to see where
| 15 mins comes from, its the time a 8l/m combi takes to fill up a small
| bath of 100l. My bath takes 180l, I'll leave that calculation to you

I am describing experiments done with a 10 litre bucket, a stop watch and a
digital thermometer. I then used the full bath and found it satisfactory.


--
Dave Fawthrop dave hyphenologist co uk
"Intelligent Design?" my knees say *not*.
"Intelligent Design?" my back says *not*.

Dave Plowman (News) wrote:
In article .com,
wrote:
Welcome back IMM.

The sock puppet returns...

The leader of the moron pack is at it again. I have literally given put
reading most of what they write as it is totally predicable and not
much value at all.


--
*Why doesn't glue stick to the inside of the bottle?

Dave Plowman London SW
To e-mail, change noise into sound.

Dave Plowman (News) wrote:
In article .com,
wrote:
Welcome back IMM.

The sock puppet returns...

The leader of the moron pack is at it again. I have literally given put
reading most of what they write as it is totally predicable and not
much value at all.

--
*Why doesn't glue stick to the inside of the bottle?

Dave Plowman London SW
To e-mail, change noise into sound.

Dave Plowman (News) wrote:
In article .com,
wrote:
Welcome back IMM.

The sock puppet returns...

The leader of the moron pack is still at it. Most of this thread is
infested with them.

--
*Why doesn't glue stick to the inside of the bottle?

Dave Plowman London SW
To e-mail, change noise into sound.

In article , Dave Fawthrop
writes
On Wed, 14 Sep 2005 08:38:17 +0100, David
wrote:

| In article , Dave Fawthrop
| writes
| On Tue, 13 Sep 2005 20:08:33 +0100, "Dave Plowman (News)"
| wrote:
|
| | In article ws.net,
| | Doctor Drivel wrote:
| | As many of the idiots on this thread spurted forth, combis are full of
| | silly old wives tales, which are untrue, pasing off old crap models as
| | the norm. Want two baths to be filled simultaneously? One can do it.
| | Just choose the model.
| |
| | Some of us are used to 25 litres plus per minute of piping hot water to
| | fill our baths regardless of external conditions.
|
| Maybe I have seen that a few times in hotels, never at home. I find 8l/m,
| measured, perfectly satisfactory. Fills a bath in about 7 mins, as would
| the proposed combi. I have set my conventional system to simulate the
| proposed combi and there is little difference between what I have now and
| the proposed combi. I have no idea where people get 15 mins for a bath
| from, maybe it is an Urban Legend.
|
| What do you do, just wash your feet? or are you talking about a baby
| bath? 56 litres is about half of a small bath so its easy to see where
| 15 mins comes from, its the time a 8l/m combi takes to fill up a small
| bath of 100l. My bath takes 180l, I'll leave that calculation to you

I am describing experiments done with a 10 litre bucket, a stop watch and a
digital thermometer. I then used the full bath and found it satisfactory.

So how big is your bath then? and would you say you like a
hot/warm/medium bath? would you say you a standard human being?

--
David

Dave Fawthrop wrote:

"Are you satisfied with hot water from a combi boiler, without extra
storage".

Abundantly.
we have 14 l/min at 30 degree temp rise so running at 55 degrees HW temp
gives more than ample supply for shower, and as we rarely use baths
anyway, it's still well ample for a bath fill when 'er self want's a soak.

I used to have a HW tank heated from a backboiler with a "real"
powershower pump feeding a mixer shower. The HW tank would empty in
about 7 minutes and the shower would then run tepid.

So, a combi is the dogs bollarks. I would never go back to stored HW.

--
http://gymratz.co.uk - Best Gym Equipment & Bodybuilding Supplements UK.
http://trade-price-supplements.co.uk - TRADE PRICED SUPPLEMENTS for ALL!
http://fitness-equipment-uk.com - UK's No.1 Fitness Equipment Suppliers.
http://gymratz.co.uk/hot-seat.htm - Live web-cam! (sometimes)

In article .com,
wrote:
The sock puppet returns...

The leader of the moron pack is at it again. I have literally given put
reading most of what they write as it is totally predicable and not
much value at all.

But at least it's English...

And posted only once...

--
*If a turtle doesn't have a shell, is he homeless or naked?

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Dave Fawthrop wrote:
| What do you do, just wash your feet? or are you talking about a baby
| bath? 56 litres is about half of a small bath so its easy to see where
| 15 mins comes from, its the time a 8l/m combi takes to fill up a small
| bath of 100l. My bath takes 180l, I'll leave that calculation to you

I am describing experiments done with a 10 litre bucket, a stop watch
and a digital thermometer. I then used the full bath and found it
satisfactory.

You are of course entitled to your opinion. But most who like a decent
bath would disagree with you. I like a bath to fill in the time it takes
to get undressed etc.

--
*Husbands should come with instructions

Dave Plowman London SW
To e-mail, change noise into sound.

In message .com,
writes

Dave Plowman (News) wrote:
In article .com,
wrote:
Welcome back IMM.

The sock puppet returns...

The leader of the moron pack is at it again.


I have literally given put
reading most of what they write

Aha dIMM speak at last




--
geoff

Out of curiosity could you take a guess at how many kW of combi boiler
power would be required to fill a bath at the same rate as a stored
hot water system?

In article ,
Peter wrote:
Out of curiosity could you take a guess at how many kW of combi boiler
power would be required to fill a bath at the same rate as a stored
hot water system?

It would depend on the stored system, as some can be very poor.

--
*If you try to fail, and succeed, which have you done?

Dave Plowman London SW
To e-mail, change noise into sound.

On Thu, 15 Sep 2005 09:34:17 +0100, Peter wrote:

Out of curiosity could you take a guess at how many kW of combi boiler
power would be required to fill a bath at the same rate as a stored
hot water system?

It depends on how effective your 'stored' arragements are but if you took
a typical 20 litre/min of mixed water (a correctly installed unvented
system might well give twice that). The you'd be looking at around 50kW
more or less depending on the inlet water temp.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html

On Wed, 14 Sep 2005 19:19:51 +0100, "Dave Plowman (News)"
wrote:


| You are of course entitled to your opinion. But most who like a decent
| bath would disagree with you. I like a bath to fill in the time it takes
| to get undressed etc.

Well I have no problem getting undressed in 30 sec, so with your 100l bath,
you must have 200l/min. I very much doubt it.

--
Dave Fawthrop dave hyphenologist co uk
"Intelligent Design?" my knees say *not*.
"Intelligent Design?" my back says *not*.

In article , Dave Fawthrop
wrote:
On Wed, 14 Sep 2005 19:19:51 +0100, "Dave Plowman (News)"
wrote:


| You are of course entitled to your opinion. But most who like a decent
| bath would disagree with you. I like a bath to fill in the time it
| takes to get undressed etc.

Well I have no problem getting undressed in 30 sec, so with your 100l
bath, you must have 200l/min. I very much doubt it.

Fine. I'll give you some figures. I get near 30 l/min of hot at 60C and
the same flow rate of 'cold' at probably around 10C since it comes from a
storage tank too. So it fills the bath in *about* the same time as it
takes to get undressed and get organised for a bath. If I'm in a rush to
get washed, I use the shower. Which also delivers the same sort of flow -
being an Aqualisa fed from 22mm.

If you'd care to recommend a combi which can match this I'll buy it
tomorrow. Unless, of course, it needs a commercial gas supply, etc.

--
*The fact that no one understands you doesn't mean you're an artist

Dave Plowman London SW
To e-mail, change noise into sound.

In message , "Dave Plowman (News)"
writes
In article ,
Peter wrote:
Out of curiosity could you take a guess at how many kW of combi boiler
power would be required to fill a bath at the same rate as a stored
hot water system?

It would depend on the stored system, as some can be very poor.

It also depends if the combi is limited e.g. to 10l/min as in the Worcs
28i Junior

--
geoff

...you'd be looking at around 50kW
more or less depending on the inlet water temp.

Thanks Ed. That's quite some power for sure. I was concerned about
that. So I would be needing a very big gas combi or a three-phase
supply to drive some fancy, semi-industrial, Stiebel-Eltron kind of
electric device.

Dave Plowman (News) wrote:
In article , Dave Fawthrop
wrote:
On Wed, 14 Sep 2005 19:19:51 +0100, "Dave Plowman (News)"
wrote:


| You are of course entitled to your opinion. But most who like a decent
| bath would disagree with you. I like a bath to fill in the time it
| takes to get undressed etc.

Well I have no problem getting undressed in 30 sec, so with your 100l
bath, you must have 200l/min. I very much doubt it.

Fine. I'll give you some figures. I get near 30 l/min of hot at 60C and
the same flow rate of 'cold' at probably around 10C since it comes from a
storage tank too. So it fills the bath in *about* the same time as it
takes to get undressed and get organised for a bath. If I'm in a rush to
get washed, I use the shower. Which also delivers the same sort of flow -
being an Aqualisa fed from 22mm.

If you'd care to recommend a combi which can match this I'll buy it
tomorrow. Unless, of course, it needs a commercial gas supply, etc.

The ACV Heatmaster 35 KW combi supplies 38 litres per minute of hot
water at 60 degree C. I have all the details. As you are now going to
buy one as it beats your 30 litres, take out a loan tomorrow as you
have clearly stated.

30 litres a minute from a tank in the loft? I would say 28mm pipes and
3/4" single bath taps to get that. Who has single taps anymore? I have
only ever seen them in hospitals. I only ever fit mixers which do lower
the combined flow. Single taps lower the price of a place.

Peter wrote:
...you'd be looking at around 50kW
more or less depending on the inlet water temp.

Thanks Ed. That's quite some power for sure. I was concerned about
that. So I would be needing a very big gas combi or a three-phase
supply to drive some fancy, semi-industrial, Stiebel-Eltron kind of
electric device.

Peter,

There are stored water combis. They have everything in one box with
some stored water inside. You don't get too concerned about the
innards. The ACV Heatmaster will deliver 38 litres per minute and is
only 35 KW. The domestic meter will deliver around 60 KW. 35KW is just
over half of the meter capacity, so just ticking over. The Powermax,
Gledhill and Viessmann both have high flowrates as well.

The Japanese Rinnai multi points have high flowrates with the downside
of no CH. I am seriously in the market for one of these.

On 15 Sep 2005 15:48:37 -0700, wrote:


The ACV Heatmaster 35 KW combi supplies 38 litres per minute of hot
water at 60 degree C. I have all the details.


Clearly you haven't read them properly, or have just looked at the
glossy brochure. Have you been taking dIMM pills.?

That is the short term peak value.

The HM35TC is claimed to be able to deliver 224 litres per 10 minutes
at 60 degrees.

However, the constant flow rate is 9.6 litres per minute at the same
temperature rise of 50 degrees. At the more commonly quoted
temperature rise of 35 degrees, the constant flow rate is 15 litres
per minute which is as predicted by the appliance rating.

They conveniently omit what the size of hot water storage actually is,
so that one cannot determine the real performance of the system.

The sales brochure describes the unit as "light weight". Hmmm... the
spec. says 170kg empty.

It's also described as "small". The actual size is 670 x 600 x 1700
which is hardly that. It won't even fit into a standard washing
machine footprint. This means that it will either be taking up
valuable space in a kitchen (which would have to configured in a
non-standard way, or to be placed in a cupboard. In effect, the size
is the same as a storage tank and there is virtually no usable space
saving compared with a conventional cylinder and separate small
boiler.

This is not to say that the design isn't reasonable in principle, but
there is considerable specmanship and hype in the way it's described.



--

..andy

To email, substitute .nospam with .gl

On 15 Sep 2005 16:00:03 -0700, wrote:


Peter wrote:
...you'd be looking at around 50kW
more or less depending on the inlet water temp.

Thanks Ed. That's quite some power for sure. I was concerned about
that. So I would be needing a very big gas combi or a three-phase
supply to drive some fancy, semi-industrial, Stiebel-Eltron kind of
electric device.

Peter,

There are stored water combis. They have everything in one box with
some stored water inside. You don't get too concerned about the
innards.

You should be.


The ACV Heatmaster will deliver 38 litres per minute and is
only 35 KW.

It will do that for an unspecified short time. Refer to other post.

The domestic meter will deliver around 60 KW. 35KW is just
over half of the meter capacity, so just ticking over. The Powermax,
Gledhill and Viessmann both have high flowrates as well.

For a short period. It is not possible to get a quart from a pint
pot.



The Japanese Rinnai multi points have high flowrates with the downside
of no CH. I am seriously in the market for one of these.

I expect that the marketing guy is rubbing his hands with glee.

--

..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On 15 Sep 2005 15:48:37 -0700, wrote:


The ACV Heatmaster 35 KW combi supplies 38 litres per minute of
hot
water at 60 degree C. I have all the details.


Clearly you haven't read them properly, or have just looked at the
glossy brochure. Have you been taking dIMM pills.?
snip

I suspect he is dIMM....

wrote in message
oups.com...

snip
the combined flow. Single taps lower the price of a place.


Total crap, if there is either a separate shower enclosure or mixer
were is the need for mixer taps?

Andy Hall wrote:
On 15 Sep 2005 15:48:37 -0700, wrote:

The ACV Heatmaster 35 KW combi supplies 38 litres per minute of hot
water at 60 degree C. I have all the details.

Clearly you haven't read them properly, or have just looked at the
glossy brochure. Have you been taking dIMM pills.?

That is the short term peak value.

The HM35TC is claimed to be able to deliver 224 litres per 10 minutes
at 60 degrees.

60 degrees? Do you want to have third degree burns? Do you know how hot
that is?

However, the constant flow rate is 9.6 litres per minute at the same
temperature rise of 50 degrees. At the more commonly quoted
temperature rise of 35 degrees, the constant flow rate is 15 litres
per minute which is as predicted by the appliance rating.

I downloaded the installation manual. Here are the figures pasted in
for you, which are very impressive:
----------
DOMESTIC HOT WATER FEATURES
HeatMaster=C2=AE
Operating conditions at 80=C2=B0C 35 TC

Peak flow at 40=C2=B0C [=CE=94T =3D 30=C2=B0C] L/10=E2=80=99 419
Peak flow at 40=C2=B0C [=CE=94T =3D 30=C2=B0C] L/60=E2=80=99 1312
Constant flow at 40=C2=B0C [=CE=94T =3D 30=C2=B0C] L/h 1057
Peak flow at 45=C2=B0C [=CE=94T =3D 35=C2=B0C] L/10=E2=80=99 381
Peak flow at 45=C2=B0C [=CE=94T =3D 35=C2=B0C] L/60=E2=80=99 1080
Constant flow at 45=C2=B0C [=CE=94T =3D 35=C2=B0C] L/h 898
Peak flow at 60=C2=B0C [=CE=94T =3D 50=C2=B0C] L/10=E2=80=99 224
Peak flow at 60=C2=B0C [=CE=94T =3D 50=C2=B0C] L/60=E2=80=99 692
Constant flow at 60=C2=B0C [=CE=94T =3D 50=C2=B0C] L/h 578

Pre-heat time minutes 37
---------

It will deliver 381 litres for 10 minutes at a sensible 45C. That is 38
litres per minute, then drops down to 15 litres per minute continuously
never running out of hot water. Many people on this thread are happy
with less than 15 litres per minutes from their combis. Two
simultaneous baths can be filled. The mains pipe temperature is around
20C at the moment, the ACV would right now deliver 42 litres per minute
for 10 minutes, then down to near 18 litres per minute. That will fill
a large jacuzzi no problem at all. The figures are very impressive and
I have no reason to disbelieve them as ACV are largely in the
commercial market. The new Scottish Parliament building has banks of
Heatmasters. See the ACV web site.

They conveniently omit what the size of hot water storage actually is,
so that one cannot determine the real performance of the system.

The sales brochure describes the unit as "light weight". Hmmm... the
spec. says 170kg empty.

It's also described as "small". The actual size is 670 x 600 x 1700
which is hardly that. It won't even fit into a standard washing
machine footprint. This means that it will either be taking up
valuable space in a kitchen (which would have to configured in a
non-standard way, or to be placed in a cupboard. In effect, the size
is the same as a storage tank and there is virtually no usable space
saving compared with a conventional cylinder and separate small
boiler.

There is space savings. No boiler in the kitchen, which are a pain and
restricts kitchen design, which is great bonus for me. The ACV can go
in then loft like the Powermaxes. A bit of a lift but possible. I asked
ACV about loft mounting they said no problems as the unit is well
insulated.

This is not to say that the design isn't reasonable in principle, but
there is considerable specmanship and hype in the way it's described.

I don't quite understand how it works in detail. ACV have configured a
lower chamber to force cool water for the condensing operation. Perhaps
IMM/Evil can explain. It is all stainless steel which says a lot. I
would not say there is hype in the table I pasted above. It is very
clear. Having over the past 7 years looked at combis that save space
and deliver high flows, the ACV is the most impressive I have seen by
far. It is also one of the most efficient boioers around, whoch is a
good plus point on selling. A rennovated house with a high efficient
quality boiler makes it easier to sell. I=E2=80=99m not sure if it is up to
high continuous flows that the Rinnai delivers for a couple of
simultaneous Tower Showers. The ACV is on the shortlist for the next
job, as is a Rinnai.
=20
=20
--=20
=20
.andy
=20
To email, substitute .nospam with .gl

:::Jerry:::: wrote:
wrote in message
oups.com...

snip
the combined flow. Single taps lower the price of a place.


Total crap, if there is either a separate shower enclosure or mixer
were is the need for mixer taps?

I wish all my buyers were as easy to please as you, as I would save a
fortune and put in cheap contractor materials.

Andy Hall wrote:
On 15 Sep 2005 16:00:03 -0700, wrote:


Peter wrote:
...you'd be looking at around 50kW
more or less depending on the inlet water temp.

Thanks Ed. That's quite some power for sure. I was concerned about
that. So I would be needing a very big gas combi or a three-phase
supply to drive some fancy, semi-industrial, Stiebel-Eltron kind of
electric device.

Peter,

There are stored water combis. They have everything in one box with
some stored water inside. You don't get too concerned about the
innards.

You should be.

I am only interested in what the combi delivers in flowrates. How it
works inside is only of passive interest.

The ACV Heatmaster will deliver 38 litres per minute and is
only 35 KW.

It will do that for an unspecified short time. Refer to other post.

Please do refer to my other post. The time is not unspecified, it is
clearly 10 minutes. It will fill a 380 litre bath in 10 minutes and a
normal bath in a few minutes.

The domestic meter will deliver around 60 KW. 35KW is just
over half of the meter capacity, so just ticking over. The Powermax,
Gledhill and Viessmann both have high flowrates as well.

For a short period. It is not possible to get a quart from a pint
pot.

The Powermax, Gledhill and Viessmann are all two bathroom models, and
then drop down to basic low flow continuously. The high flows are
enough to fill baths and have two simultaneous showers.


The Japanese Rinnai multi points have high flowrates with the downside
of no CH. I am seriously in the market for one of these.

I expect that the marketing guy is rubbing his hands with glee.

He should be as they are the biggest seller in the world. I'm off to
Travis Perkins now.

--

.andy

To email, substitute .nospam with .gl

In article .com,
writes

:::Jerry:::: wrote:
wrote in message
oups.com...

snip
the combined flow. Single taps lower the price of a place.


Total crap, if there is either a separate shower enclosure or mixer
were is the need for mixer taps?

I wish all my buyers were as easy to please as you, as I would save a
fortune and put in cheap contractor materials.

I think you're stretching it a bit timegoesby, how much do single taps
lower the price by? and have you had any experiences specifically about
that?

--
David