I am about to install a new combi system in a four-bed house - don't
lecture me on tanks please - but I am unsure about combi capacity. Is
bigger flow always better, equalling buying the most expensive boiler
I can afford basically? For this little excercise, capital cost for
the boiler shall not be important, I am interested in the priniciple
rather the practical.

Fred

On Sat, 11 Sep 2004 23:57:46 +0000 (UTC), (Fred)
wrote:

I am about to install a new combi system in a four-bed house - don't
lecture me on tanks please - but I am unsure about combi capacity. Is
bigger flow always better, equalling buying the most expensive boiler
I can afford basically? For this little excercise, capital cost for
the boiler shall not be important, I am interested in the priniciple
rather the practical.

Fred

In this case, bigger is better.

Combi boilers are specified in terms of the rate of flow that they can
achieve for a given temperature rise - usually 35 degrees, but do
check specs.

In the winter time, this figure will equate to the maximum flow for a
shower or for filling a bath. Considering that a bath needs 100
litrres for little more than a splash in the bottom or 150litres plus
for a reasonable one, then a typical 13lpm combi will take 10 - 15
minutes to fill it at 40 degrees. You need to decide whether you
are OK with this.

There are domestic combis with flow rates of 22lpm, which is obviously
a lot better, but these are not at the cheap end of the scale.

For almost all with any significant power level, an upgrade to 22mm or
above of the gas pipe from the meter to the appliance is needed if it
hasn't been done already.


..andy

To email, substitute .nospam with .gl

In message , Andy Hall
writes
On Sat, 11 Sep 2004 23:57:46 +0000 (UTC), (Fred)
wrote:

I am about to install a new combi system in a four-bed house - don't
lecture me on tanks please - but I am unsure about combi capacity. Is
bigger flow always better, equalling buying the most expensive boiler
I can afford basically?

In this case, bigger is better.

snip
In the winter time, this figure will equate to the maximum flow for a
shower or for filling a bath. Considering that a bath needs 100
litrres for little more than a splash in the bottom or 150litres plus
for a reasonable one, then a typical 13lpm combi will take 10 - 15
minutes to fill it at 40 degrees. You need to decide whether you
are OK with this.

We have an average mid sized combi, 100,000 btu DHW heating capacity -
about 15 l/m or so max (for decent water temp) IIRC, we are happy with
this, but I certainly wouldn't suggest going for anything smaller. We
are a shower family -except 3 yr old daughter so bath filling isn't an
issue. Bigger would be better, but depending on your requirements not
necessarily worth it.

For almost all with any significant power level, an upgrade to 22mm or
above of the gas pipe from the meter to the appliance is needed if it
hasn't been done already.

Yep, ours needed 22mm up to I think 3m of boiler, According to my
plumber neighbour some larger ones require 28mm
--
Chris French, Leeds

(Fred) wrote in message ...
I am about to install a new combi system in a four-bed house - don't
lecture me on tanks please - but I am unsure about combi capacity. Is
bigger flow always better, equalling buying the most expensive boiler
I can afford basically? For this little excercise, capital cost for
the boiler shall not be important, I am interested in the priniciple
rather the practical.

Fred

Look at IMMs recent overview of combis, he is the expert on this group
for this sort of stuff. His post is excellent. I just did a Google
search on "Combined Primary Storage Unit" and it came up. The higher
rate of water flow is the figure you should be going for. The higher
the better. IMM did suggest installing "two" Worcester Bosch Junior
combi boilers for two bathroom houses with one doing the heating for
upstairs and one for downstairs, zoning the house off. I like this
idea. I think he suggested combining the hot water outlet to give a
higher rate of water flow using check valves. This was a cheap way of
having higher rates of flow as two of these boilers is not expensive.
Do a Google on "Junior" and that may bring it up. I noticed that B&Q
do the Biasi combi boilers for around £390. Having two of these gives
around 21 litres of water flow for less than £800. Not bad at all. If
you are fitting yourself, a combi is a doddle. Cylinders and tanks can
be difficult and very time consuming to install if you want to do a
professional looking job.

In article ,
timegoesby wrote:
Look at IMMs recent overview of combis, he is the expert on this group
for this sort of stuff. His post is excellent.

While you're entitled to your view, there are far more authoritative
sources available on here than IMM. People who actually install and use
these things in anger - not just quote makers' best scenario claims as IMM
does, while never giving the downside.

I'm not an expert in heating, but a fair expert in sorting out the wheat
from the chaff in reading newsgroups. And IMM is mainly chaff.

--
*Hard work pays off in the future. Laziness pays off now *

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

In article ,
timegoesby wrote:
If you are fitting yourself, a combi is a doddle. Cylinders and tanks
can be difficult and very time consuming to install if you want to do a
professional looking job.

Assuming you're not a pro, or 'doing up' a house to sell, installing a
central heating and hot water system in your own house is probably the
biggest single expense you'll have.

And most with any sense will take the care to find out the very best
possible system for their needs regardless of whether it can be thrown in
quickly or needs some thought and care in installing. Because a decent
system will have a very long satisfactory life. A poorly installed under
specced one will annoy from day one.

As regards making a tidy job of pipework, I learned how to do it - largely
self taught. It's not particularly difficult in terms of the things many
DIY - and indeed needs little in the way of expensive tools.

--
*I used to have an open mind but my brains kept falling out *

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

In message , timegoesby
writes
(Fred) wrote in message
.. .
I am about to install a new combi system in a four-bed house - don't
lecture me on tanks please - but I am unsure about combi capacity. Is
bigger flow always better, equalling buying the most expensive boiler
I can afford basically? For this little excercise, capital cost for
the boiler shall not be important, I am interested in the priniciple
rather the practical.

Fred

Look at IMMs recent overview of combis, he is the expert on this group
for this sort of stuff. His post is excellent.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!

--
Chris French, Leeds

Andy Hall wrote:

In this case, bigger is better.

Combi boilers are specified in terms of the rate of flow that they can
achieve for a given temperature rise - usually 35 degrees, but do
check specs.

I have a hard time to beat the Worcester Bosch 40 Greenstar with a
flow rate of 16l/min. Baxi, Vaillant and the lot do not seem to match
even this. Where can I find bigger flow rated boilers then?

For almost all with any significant power level, an upgrade to 22mm or
above of the gas pipe from the meter to the appliance is needed if it
hasn't been done already.

That seems to be the right choice anyhow. Too bad that in my case that
is going to be necessary. At least that is what the plumber said and
he seems trustworthy. Speaking of trustworthy, how do you gauge a
plumber? I go by gut feeling and things like this: warnings that the
pipe needs upgrading and so on, and what are the implications of a
condensing boiler yadayada. I am not savvy enough to ask him much
more. As long as he can beat a British Gas quote, I am usually not
concerned about money too much anymore. Is that about right?

Fred

In message , "Dave Plowman (News)"
writes
In article ,
timegoesby wrote:
Look at IMMs recent overview of combis, he is the expert on this group
for this sort of stuff. His post is excellent.

While you're entitled to your view, there are far more authoritative
sources available on here than IMM. People who actually install and use
these things in anger - not just quote makers' best scenario claims as IMM
does, while never giving the downside.

I'm not an expert in heating, but a fair expert in sorting out the wheat
from the chaff in reading newsgroups. And IMM is mainly chaff.

When it's not cha cha chaf

--
geoff

On Sun, 12 Sep 2004 16:21:06 +0000 (UTC), (Fred)
wrote:

Andy Hall wrote:

In this case, bigger is better.

Combi boilers are specified in terms of the rate of flow that they can
achieve for a given temperature rise - usually 35 degrees, but do
check specs.

I have a hard time to beat the Worcester Bosch 40 Greenstar with a
flow rate of 16l/min. Baxi, Vaillant and the lot do not seem to match
even this. Where can I find bigger flow rated boilers then?

http://www.man-heiztechnik.de/index_e.php

Look at Micromat EC range.

Sold badged in the UK by Eco Hometec and MHS Boilers.
The EC38 will deliver 46kW to hot water and give 22lpm.

Viessmann (www.viessmann.de) have them in the 18-22lpm range.


For almost all with any significant power level, an upgrade to 22mm or
above of the gas pipe from the meter to the appliance is needed if it
hasn't been done already.

That seems to be the right choice anyhow. Too bad that in my case that
is going to be necessary. At least that is what the plumber said and
he seems trustworthy. Speaking of trustworthy, how do you gauge a
plumber? I go by gut feeling and things like this: warnings that the
pipe needs upgrading and so on, and what are the implications of a
condensing boiler yadayada. I am not savvy enough to ask him much
more. As long as he can beat a British Gas quote, I am usually not
concerned about money too much anymore. Is that about right?

Ask for references? Get competitive quotes. Obviously check CORGI
registration.

It is easy to beat a BG quote. I could do that, pay for CORGI
membership and insurance and still be under a BG price.




Fred

..andy

To email, substitute .nospam with .gl

On Sun, 12 Sep 2004 16:58:19 GMT, raden wrote:

In message , "Dave Plowman (News)"
writes
In article ,
timegoesby wrote:
Look at IMMs recent overview of combis, he is the expert on this group
for this sort of stuff. His post is excellent.

While you're entitled to your view, there are far more authoritative
sources available on here than IMM. People who actually install and use
these things in anger - not just quote makers' best scenario claims as IMM
does, while never giving the downside.

I'm not an expert in heating, but a fair expert in sorting out the wheat
from the chaff in reading newsgroups. And IMM is mainly chaff.

When it's not cha cha chaf


Or Tango Oscar Sierra Sierra




..andy

To email, substitute .nospam with .gl

"Dave Plowman (News)" wrote in message ...
In article ,
timegoesby wrote:
Look at IMMs recent overview of combis, he is the expert on this group
for this sort of stuff. His post is excellent.

While you're entitled to your view, there are far more authoritative
sources available on here than IMM. People who actually install and use
these things in anger - not just quote makers' best scenario claims as IMM
does, while never giving the downside.

I'm not an expert in heating,

Thank you. That is all I need to know.
The most authoritative person in this group on heating and water
systems is by a mile IMM. Any half intelligent person can see that.
Please take your ridiculous prejudices elsewhere, I don't want to
know.

"Dave Plowman (News)" wrote in message ...
In article ,
timegoesby wrote:
If you are fitting yourself, a combi is a doddle. Cylinders and tanks
can be difficult and very time consuming to install if you want to do a
professional looking job.

Assuming you're not a pro, or 'doing up' a house to sell, installing a
central heating and hot water system in your own house is probably the
biggest single expense you'll have.

And most with any sense will take the care to find out the very best
possible system for their needs regardless of whether it can be thrown in
quickly or needs some thought and care in installing. Because a decent
system will have a very long satisfactory life. A poorly installed under
specced one will annoy from day one.

As regards making a tidy job of pipework, I learned how to do it - largely
self taught. It's not particularly difficult in terms of the things many
DIY - and indeed needs little in the way of expensive tools.

Good advice, and I do consider all alternatives that is why I
occasionally look into this group and Google on it. I have fitted
tanks and cylinders and they are a time consuming pain to fit with
pipes all over the show. A good combi is cheaper to fit with far less
hassle and gives the same, if not better, performance. I previously
took IMMs advice and fitted a combi with the water section supplying
only the showers. The CH side, besides heating the radiators, heated a
very large combination cylinder to fill two baths quickly and it
worked very well. Doing it again I would consider one very large combi
or two smaller combi boilers. Two smaller combi boilers is cheap and
quick to install, and far less hassle than tanks and cylinders. I have
also been looking into heat banks and no matter how I assess, one
large or two small combi boilers comes out the best option all around
for me.

good night.

In article ,
timegoesby wrote:
I'm not an expert in heating,

Thank you. That is all I need to know.

*******************

From: timegoesby
Subject: Combi fans: is bigger better
Date: Mon, 13 Sep 2004 02:30
Newsgroups: uk.d-i-y

As regards making a tidy job of pipework, I learned how to do it -
largely self taught. It's not particularly difficult in terms of the
things many DIY - and indeed needs little in the way of expensive
tools.

Good advice

***********


Please make up your mind.

--
*I went to school to become a wit, only got halfway through.

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

"timegoesby" wrote in message
m...
"Dave Plowman (News)" wrote in message
...
In article ,
timegoesby wrote:
Look at IMMs recent overview of combis, he is the expert on this group
for this sort of stuff. His post is excellent.

While you're entitled to your view, there are far more authoritative
sources available on here than IMM. People who actually install and use
these things in anger - not just quote makers' best scenario claims as
IMM
does, while never giving the downside.

I'm not an expert in heating,

Thank you. That is all I need to know.

That is all you need to know!!!! Don't take advice from people who think
they know but know very little at all. That can be very dangerous.

"Christian McArdle" wrote in message
. net...
I have also been looking into heat banks and no matter how I assess,
one large or two small combi boilers comes out the best option all
around for me.

You should remember that a standard heat bank is good for around 40lpm (at
60C). This is equivalent to 63lpm in combi delta Ts. That would require 5
cheap instantaneous combi boilers and a commercial gas supply to run them.

That is nearly true. But most people don't need a commercial setup. Most
people are content on a bath fill of 5 minutes and a excellent showers. A
combi, or combi's, can do that with less hassle in installation and lower
cost .

Depensing on how a boiler is conected to a heat bank (dirrect with a
blending valve is the best) you will run out of hot water. Two small combi's
will never. The teenagers can stay in the shower all day. Flowrates are
important up to a point, but you have to look at the big picture.

It is required if you wish to fill a bath in 2 minutes, which, for me, is
an
essential characteristic.

In most homes that would lead to floods.

"raden" wrote in message
...
In message , "Dave Plowman (News)"
writes
In article ,
timegoesby wrote:
Look at IMMs recent overview of combis, he is the expert on this group
for this sort of stuff. His post is excellent.

While you're entitled to your view, there are far more authoritative
sources available on here than IMM. People who actually install and use
these things in anger - not just quote makers' best scenario claims as
IMM
does, while never giving the downside.

I'm not an expert in heating, but a fair expert in sorting out the wheat
from the chaff in reading newsgroups. And IMM is mainly chaff.

When it's not cha cha chaf

Maxie,nice one. Nice to see you are in good spirits. Good for your soul.

"Fred" wrote in message
...
Andy Hall wrote:

In this case, bigger is better.

Combi boilers are specified in
terms of the rate of flow that they can
achieve for a given temperature rise - usually
35 degrees, but do check specs.

I have a hard time to beat the Worcester
Bosch 40 Greenstar with a flow rate of 16l/min.
Baxi, Vaillant and the lot do not seem to match
even this. Where can I find bigger flow rated boilers then?

The Greenstar is a v good boiler, with a good flowrate and well priced too.

At least that is what the plumber said and
he seems trustworthy. Speaking of trustworthy,
how do you gauge a plumber?

The thing to do is know your specification and ask them to quote on it. The
Greenstar is a god choice, so go for that, do not be persuaded otherwise.
It does require a 28mm gas supply, but can be reduced to 22mm towards the
boiler depending on the run. Tell him that you checked wityh the maer on the
gas pipe size. Some cowboys would keep, or fit, 22mm.

Go on recommendations and ask them to quote. Combi's are easy to fit, even
for a dumb plumber, so not that much to go wrong.

"Fred" wrote in message
...

I have a hard time to beat the Worcester Bosch 40 Greenstar with a
flow rate of 16l/min. Baxi, Vaillant and the lot do not seem to match
even this. Where can I find bigger flow rated boilers then?

Fred, read on, if you haven't read this already:

Go for a high flow combi, if the water mains flow is OK, such as:

1. Vaillant AquaPlus
2. Alpha CB50
3. Worcester-Bosch Greenstar 40kW (condensing boiler)

A combi explanation for you....

Firstly, a combi is a "combination" of the heating and water system in one
case, eliminating external tanks and cylinders, and generally supply hot
water at high main pressure. To confuse a little, some can run at very low
pressures and even off tanks. Generally most are fed from the mains. It is
generally a matter of mounting the boiler and connect up the pipes. The
expert designers have done the hard work for you and put all in one case.

There are three types of combi:

1) The Infinitely Continuous Combi -

Heats cold mains water instantly as it runs through the combi. It never runs
out of hot water. This is the most common type of combi, generally having
lower flowrates than Nos 2 & 3 below. The largest flow rate instant combi is
a two bathroom model, 22 litres/min ECO-Hometec. Being a condenser it is
very economical too. http://www.eco-hometec.co.uk

2) Unvented Cylinder Combi -

An unvented cylinder is a similar to a conventional cylinder but run off the
high-pressure cold mains. A combi with an integral unvented cylinder has
approx 60 litre cylinder heated to approx 80C, with a quick recovery coil
that takes all the boilers output. A fast acting cylinder thermostat ensures
the boiler pumps heat into the cylinder ASAP with a recovery rate from cold
around 5-8 mins (Ariston claim 8 mins). The 80C water is blended down to
about 45-50C. e.g's, Ariston Genus 27 Plus, Glow Worm, Powermax, Alpha
CB50.

3) Infinately Continuous/Unvented cylinder combi -

An example being the Alpha CB50, a combination of both having a two stage
flowrate, of high flowrate when using the stored water with an automatic
flow regulator switching in to reduce flow to an invinately continuous
flowrate of approx 11 litres/min.
http://www.alpha-boilers.com/products/CB50.html

4) Heat Bank Combi -

Incoming water is instantly heated running through a plate heat exchanger
(as is most instantaneous combi's) that takes its heat from a "domestic hot
water only" store of water at approx 80C (instantaneous combi's take the
heat from a heat-exchanger heater via the burner). A fast acting thermostat
ensures the boiler pumps all of its heat into the store ASAP with a recovery
rate about 5-8 mins from cold. The 80C water is blended down to about
45-50C. They are generally two stage flow rates, in that when the thermal
store is exhausted it reverts to what the burner can produce, which is
approx 11-12 litre/minute. e.g. Vokera & Worcester floor standing models
(standard washing machine sizes).

N.B. The heat bank is a variation of a thermal store, but is "not" a thermal
store in the conventional sense in that a coil carrying cold mains water
runs though a store of hot water kept at about 80C. Heat-banks are far more
efficient and give higher flowrates than conventional coiled thermal stores.
The stainless steel plate heat-exchangers do not scale up so easily.

5) Combined Primary Storage Unit

(Not classed as a combi, but a derivative of a combi, but still a one box
solution, so still in the same family)

These are a combination of a large thermal store, or heat bank, and boiler
in one casing. The units are large (larger than standard washing machine
size) and floor mounted. The heating is taken off the thermal store, which
in many cases the DHW taken off the store using a plate heat-exchanger
(heat-bank). Unlike the Heat-bank in 3) above the thermal store supplies
heating "and" DHW, giving the "combined" to the title. They are available
from 1 to 2.5 bathroom models. Gledhill do an excellent condensing
version, the Gulfsream 2000. http://www.gledhill.net

Nos. 2), 3), 4) & 5) have high flowrates. No. 1 "generally" has low
flowrates but there are always exceptions and some can be high - e.g. the
ECO-Hometec infinitely continuous combi, actually has a very high flowrate.
Nos 2), 3), 4) & 5) use stored water, but in different ways. Unlike No. 1
"some" versions will eventually run cold, but that takes quite a time, hence
some are referred to as "two bathroom" models, having the ability to fill
two
baths with very fast recovery rates. As hot water is being drawn off the
high rating burner is also reheating. Very rare do these combi's run out of
hot water in average use. When taking one shower the burner may be
re-heating faster than what can be drawn-off. No. 3) above uses stored
water but will not run out of hot water (high and low flowrates). Most
versions of No. 4) above are two stage flowrate models (high and low
flowrates) and will also not run out of hot water.

There are combi models that give hot water and heating simultaneously as
Combined Primary Storage Units do. Most don't as they are hot water
priority.

On Mon, 13 Sep 2004 16:03:13 +0100, "IMM" wrote:


"Christian McArdle" wrote in message
.net...
I have also been looking into heat banks and no matter how I assess,
one large or two small combi boilers comes out the best option all
around for me.

You should remember that a standard heat bank is good for around 40lpm (at
60C). This is equivalent to 63lpm in combi delta Ts. That would require 5
cheap instantaneous combi boilers and a commercial gas supply to run them.

That is nearly true. But most people don't need a commercial setup. Most
people are content on a bath fill of 5 minutes and a excellent showers. A
combi, or combi's, can do that with less hassle in installation and lower
cost .

Where are you going to find a domestic combi able to deliver 30lpm?



..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Mon, 13 Sep 2004 16:03:13 +0100, "IMM" wrote:


"Christian McArdle" wrote in message
.net...
I have also been looking into heat banks and no matter how I assess,
one large or two small combi boilers comes out the best option all
around for me.

You should remember that a standard heat bank is good for around 40lpm
(at
60C). This is equivalent to 63lpm in combi delta Ts. That would require
5
cheap instantaneous combi boilers and a commercial gas supply to run
them.

That is nearly true. But most people don't need a commercial setup. Most
people are content on a bath fill of 5 minutes and a excellent showers.
A
combi, or combi's, can do that with less hassle in installation and lower
cost .

Where are you going to find a domestic combi able to deliver 30lpm?

average bath is 100 litres with 2/3 to 3/4 of that hot and thebnrst cold
water. So 70/5 = 14. That is 14 litres/min, which is well short of
ECO-Hometecs 22 litres/min.

IMM wrote:

will never. The teenagers can stay in the shower all day. Flowrates are
important up to a point, but you have to look at the big picture.

Like the fact your heating would be off all day as a result of said
teenagers using DHW all the time?



--
Cheers,

John.

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

On Mon, 13 Sep 2004 20:49:42 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Mon, 13 Sep 2004 16:03:13 +0100, "IMM" wrote:


"Christian McArdle" wrote in message
.net...
I have also been looking into heat banks and no matter how I assess,
one large or two small combi boilers comes out the best option all
around for me.

You should remember that a standard heat bank is good for around 40lpm
(at
60C). This is equivalent to 63lpm in combi delta Ts. That would require
5
cheap instantaneous combi boilers and a commercial gas supply to run
them.

That is nearly true. But most people don't need a commercial setup. Most
people are content on a bath fill of 5 minutes and a excellent showers.
A
combi, or combi's, can do that with less hassle in installation and lower
cost .

Where are you going to find a domestic combi able to deliver 30lpm?

average bath is 100 litres with 2/3 to 3/4 of that hot and thebnrst cold
water. So 70/5 = 14. That is 14 litres/min, which is well short of
ECO-Hometecs 22 litres/min.


No, that's a dribble in the bottom.

Your assumption regarding 2/3 to 3/4 hot to cold ratio assumes spring
to autumn water temperatures. During the winter, the entire combi
output will be needed. At 14lpm and 150 litres - a more realistic
volume for the bath - filling will take over ten minutes.


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Mon, 13 Sep 2004 20:49:42 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Mon, 13 Sep 2004 16:03:13 +0100, "IMM" wrote:


"Christian McArdle" wrote in
message
.net...
I have also been looking into heat banks and no matter how I
assess,
one large or two small combi boilers comes out the best option all
around for me.

You should remember that a standard heat bank is good for around
40lpm
(at
60C). This is equivalent to 63lpm in combi delta Ts. That would
require
5
cheap instantaneous combi boilers and a commercial gas supply to run
them.

That is nearly true. But most people don't need a commercial setup.
Most
people are content on a bath fill of 5 minutes and a excellent
showers.
A
combi, or combi's, can do that with less hassle in installation and
lower
cost .

Where are you going to find a domestic combi able to deliver 30lpm?

average bath is 100 litres with 2/3 to 3/4 of that hot and thebnrst cold
water. So 70/5 = 14. That is 14 litres/min, which is well short of
ECO-Hometecs 22 litres/min.

No, that's a dribble in the bottom.

Your assumption regarding 2/3 to 3/4 hot to cold ratio assumes spring
to autumn water temperatures. During the winter, the entire combi
output will be needed. At 14lpm and 150 litres - a more realistic
volume for the bath - filling will take over ten minutes.

Firstly 100 litres is typical for a modern bath. Secondly, the Worcester
Bosch Greenstar 40 at 16 litres/min will do. Thridly if you have 150 litres
get it replaced as you are adding to global warming.

On Mon, 13 Sep 2004 23:08:19 +0100, "IMM" wrote:



Firstly 100 litres is typical for a modern bath.

No it isn't. I measured one and posted the results recently.

Secondly, the Worcester
Bosch Greenstar 40 at 16 litres/min will do.

Do what and who? Better than 11 or 13lpm I suppose,


Thridly if you have 150 litres
get it replaced as you are adding to global warming.


What on earth are you talking about?


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Mon, 13 Sep 2004 23:08:19 +0100, "IMM" wrote:



Firstly 100 litres is typical for a modern bath.

No it isn't.

Oh my God! He is at it again.

Secondly, the Worcester
Bosch Greenstar 40 at 16 litres/min will do.

Do what and who? Better than 11 or 13lpm I suppose,

Clear indication of poor comprehension.

Thridly if you have 150 litres
get it replaced as you are adding to global warming.

What on earth are you talking about?

He can't even get that. You are consuming more resources than what you need
to, so are totally irresponsible.

In message , IMM writes

"Andy Hall" wrote in message
.. .
On Mon, 13 Sep 2004 23:08:19 +0100, "IMM" wrote:



Firstly 100 litres is typical for a modern bath.

No it isn't.

Oh my God! He is at it again.

Secondly, the Worcester
Bosch Greenstar 40 at 16 litres/min will do.

Do what and who? Better than 11 or 13lpm I suppose,

Clear indication of poor comprehension.

Thridly if you have 150 litres
get it replaced as you are adding to global warming.

What on earth are you talking about?

He can't even get that. You are consuming more resources than what you need
to, so are totally irresponsible.

DIMM, you're consuming precious oxygen, please decease
--
geoff

In article ,
Andy Hall wrote:
Where are you going to find a domestic combi able to deliver 30lpm?

You don't need 30 lpm, Andy. IMM has said so. Why don't you trust his
judgement?

--
*He who dies with the most toys is, nonetheless, dead.

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

On Mon, 13 Sep 2004 23:34:28 +0100, "IMM" wrote:


You are consuming more resources than what you need
to, so are totally irresponsible.


It seems to me that the prize for greenhouse gas emission should go to
you........


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Mon, 13 Sep 2004 23:34:28 +0100, "IMM" wrote:


You are consuming more resources than what you need
to, so are totally irresponsible.


It seems to me that the prize for greenhouse gas emission should go to
you........

Wow....

"raden" wrote in message
...
In message , IMM writes

"Andy Hall" wrote in message
.. .
On Mon, 13 Sep 2004 23:08:19 +0100, "IMM" wrote:



Firstly 100 litres is typical for a modern bath.

No it isn't.

Oh my God! He is at it again.

Secondly, the Worcester
Bosch Greenstar 40 at 16 litres/min will do.

Do what and who? Better than 11 or 13lpm I suppose,

Clear indication of poor comprehension.

Thridly if you have 150 litres
get it replaced as you are adding to global warming.

What on earth are you talking about?

He can't even get that. You are consuming more resources than what you
need
to, so are totally irresponsible.

DIMM, you're consuming precious oxygen, please decease

Maxie, do you think I am going to cruise in on your Din Lin the far eastern
luscious lovely? Believe she is all yours. I would never take her away from
you.

"Andy Hall" wrote in message
...
On Mon, 13 Sep 2004 16:03:13 +0100, "IMM" wrote:


"Christian McArdle" wrote in message
.net...
I have also been looking into heat banks and no matter how I assess,
one large or two small combi boilers comes out the best option all
around for me.

You should remember that a standard heat bank is good for around 40lpm
(at
60C). This is equivalent to 63lpm in combi delta Ts. That would require
5
cheap instantaneous combi boilers and a commercial gas supply to run
them.

That is nearly true. But most people don't need a commercial setup. Most
people are content on a bath fill of 5 minutes and a excellent showers.
A
combi, or combi's, can do that with less hassle in installation and lower
cost .

Where are you going to find a domestic combi able to deliver 30lpm?

I am not a fan of combi boilers as they provide no back up, which you do get
with an indirect cylinder and immersion heater, and the flow rates are a bit
poor. I have, however, now experienced my second good combi boiler. The
first was in a chalet at Centre Parcs and the second at a holiday cottage in
Cornwall. They were both boxes about 1m in each direction and floor mounted,
and the cold pressure was high. They did work most satisfactorily, though.
The answer to the question posed in the subject line is "yes" (but you still
have no back-up water heating, or source of heat for the airing cupboard).


--
Bob Mannix
(anti-spam is as easy as 1-2-3 - not)

"Bob Mannix" wrote in message
...

"Andy Hall" wrote in message
...
On Mon, 13 Sep 2004 16:03:13 +0100, "IMM" wrote:


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

I have also been looking into heat banks and no matter how I
assess,
one large or two small combi boilers comes out the best option all
around for me.

You should remember that a standard
heat bank is good for around 40lpm
(at 60C). This is equivalent to 63lpm in
combi delta Ts. That would require
5 cheap instantaneous combi boilers
and a commercial gas supply to run
them.

That is nearly true. But most people don't
need a commercial setup. Most
people are content on a bath fill of 5
minutes and a excellent showers.

A combi, or combi's, can do that with less
hassle in installation and lower cost .

Where are you going to find a domestic
combi able to deliver 30lpm?

I am not a fan of combi boilers as they
provide no back up, which you do get
with an indirect cylinder and immersion heater,

An in-line instant elecric heater can be installed to supply one tap and a
shower. Not expensive and easy to do.

and the flow rates are a bit
poor.

My God not another one!!!! You can get 22 litres/minute from combi's. You
can also get 9 litres/min, which you seem to think all are like that.

I have, however, now experienced my second good combi boiler. The
first was in a chalet at Centre Parcs and the second at a holiday cottage
in
Cornwall. They were both boxes about 1m in each direction and floor
mounted,
and the cold pressure was high. They did work most satisfactorily, though.
The answer to the question posed in the subject line is "yes"

You have contradicted what you have said above when you said they have poor
flowrates.

(but you still have no back-up water heating,
or source of heat for the airing cupboard).

--
Bob Mannix
(anti-spam is as easy as 1-2-3 - not)

In article ,
IMM wrote:
I am not a fan of combi boilers as they
provide no back up, which you do get
with an indirect cylinder and immersion heater,

An in-line instant elecric heater can be installed to supply one tap and
a shower. Not expensive and easy to do.

But doesn't provide a hot water back up as an immersion does. If you just
want some water for the washing up, boiling a kettle will do in an
emergency. But not for a bath or shower.

Just as well you're not a doctor. You'd be amputating legs for a cold...

--
*Red meat is not bad for you. Fuzzy green meat is bad for you.

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

IMM wrote:

My God not another one!!!! You can get 22 litres/minute from combi's. You
can also get 9 litres/min, which you seem to think all are like that.

Two points:

You can get 180 mph from a saloon car... is yours that quick? What you
fail to allow for (yet again) is the fact that you can get 22lpm from a
combi is not relevant. Most peoples experiance is of far more modest
combis. That is because that is what tends to get recommended and
installed by their plumbers, and that is what most people are prepared
to pay for. Many people I have spoken to would not even be able to tell
you the input power of the combi they have!

Note also he did say the flow rates are "a bit poor" - not "very poor"
or "inadequate". For somone used to a good storage system 22 lpm *is* a
bit poor in comparison.

You have contradicted what you have said above when you said they have poor
flowrates.

I suggest you go and re-read the thread.

--
Cheers,

John.

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

My God not another one!!!! You can get 22 litres/minute from combi's.
You
can also get 9 litres/min, which you seem to think all are like that.

Two points:

You can get 180 mph from a saloon
car... is yours that quick?

Silly analogy.

What you fail to allow for (yet again)
is the fact that you can get 22lpm from a
combi is not relevant.

It isn't? When people say they only give poor flow and many have high flows
that is not relevant? Amazing. Must be third world logic.

Most peoples experiance is of far more modest
combis. That is because that is what tends
to get recommended

...and I recommend they get the flow to suit tneir needs and high flows are
avaiable.

and installed by their plumbers,

Plumbers? Great for drains and gutters.

and that is what most people are prepared
to pay for.

Don't gripe that your car can't do 130 mph if you bought a Lada.

Many people I have spoken to would
not even be able to tell
you the input power of the combi they have!

They don't need to. they just want it to provide the flowrates and heat the
house.

Note also he did say the flow rates
are "a bit poor" - not "very poor"
or "inadequate".

The word "poor" was there, many combi's are far from poor and are very good.

For somone used to a good storage
system 22 lpm *is* a
bit poor in comparison.

Most storage systems don't do much better, if they do. 22 l/pm will fill a
100 litre bath with 2/3 hot and the rest cold in 3 minutes and no tanks or
cylinders

You have contradicted what you have
said above when you said they have poor
flowrates.

I suggest you go and re-read the thread.

I suggest you don't comment on topics you obviously know nothing about.

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

will never. The teenagers can stay in the shower all day. Flowrates are
important up to a point, but you have to look at the big picture.

Like the fact your heating would be off all day as a result of said
teenagers using DHW all the time?

Some combi's do CH & DHW simultaneously. If you have teenagers in the shower
for excessive periods then you need to be a form parent. They will wither
in that water.

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

My God not another one!!!! You can get 22 litres/minute from combi's.
You
can also get 9 litres/min, which you seem to think all are like that.

Two points:

You can get 180 mph from a saloon car... is yours that quick? What you
fail to allow for (yet again) is the fact that you can get 22lpm from a
combi is not relevant. Most peoples experiance is of far more modest
combis. That is because that is what tends to get recommended and
installed by their plumbers, and that is what most people are prepared
to pay for. Many people I have spoken to would not even be able to tell
you the input power of the combi they have!

Note also he did say the flow rates are "a bit poor" - not "very poor"
or "inadequate". For somone used to a good storage system 22 lpm *is* a
bit poor in comparison.

You have contradicted what you have said above when you said they have
poor
flowrates.

I suggest you go and re-read the thread.

I tend not to respond to wilful misunderstandings - thanks for doing it for
me! Quite, quite and quite (to your points). I meant (and you, at least,
could clearly understand) that I had only found adequate flow rates from
rather large combis that would be impractical to install in my/most home(s).
In their place (for example a restored listed building rented out where a
"conventional" system was undesirable and the *large* combi could be put
outside) it did a fine job.


--
Bob Mannix
(anti-spam is as easy as 1-2-3 - not)

"Bob Mannix" wrote in message
...

I tend not to respond to wilful misunderstandings - thanks for doing it
for
me!

He did a lousy job for you.

Quite, quite and quite (to your points). I meant (and you, at least,
could clearly understand) that I had only found adequate flow rates from
rather large combis that would be impractical to install in my/most
home(s).

High flow combi's can be wall mounted.

In their place (for example a restored listed building rented out where a
"conventional" system was undesirable and the *large* combi could be put
outside) it did a fine job.

IMM wrote:

Like the fact your heating would be off all day as a result of said
teenagers using DHW all the time?


Some combi's do CH & DHW simultaneously. If you have teenagers in the shower

Yes _some_ do, the great majority do not, something you often fail to
point out I notice.

Perhaps you could compile a list of those you know of which are able to
provide DHW and CH simultaneously?

(I suggest this not because I doubt they exist, but because the
information might actualy be useful to someone in the future)

for excessive periods then you need to be a form parent. They will wither
in that water.

Huh? Write English please.


--
Cheers,

John.

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