I'm about to start the last major upheaval in my house.
Replaceing the ancient back-boiler.
The whole project may involve most of these:

Move or remove Water tank. I don't want it where it is it is in the way of a
subsequent minor loft conversion/over stairs mezzanine.

Move or remove water cylinder from landing to a cupboard in 3rd bedroom or
loft. Mainly for the same reason as above.

Install new boiler in 1/ under stairs, 2/ in loft 3/ somewhere else. Though
exhaust of 1/ may interfere with subsequent garage updgrade at future date.

Finally new gas fire in lounge to replace back boiler.

These are the major considerations, how else do I choose Combi boiler or
stored water?

Current shower is balanced gravity fed which is newish in a new bathroom
that I don't want to upset - though I would like to improve shower
performance possibly in conjunction with raising water tank since I need to
move/replace it. Alternatively a combi boiler would give the needed extra
pressure or I could add a pump?

As you can see I have so many variables it is hard to pin any of them down?
Where do I start?

--
Mike W

On Mon, 20 Sep 2004 17:19:43 GMT, "VisionSet"
wrote:

I'm about to start the last major upheaval in my house.
Replaceing the ancient back-boiler.
The whole project may involve most of these:

Move or remove Water tank. I don't want it where it is it is in the way of a
subsequent minor loft conversion/over stairs mezzanine.

Move or remove water cylinder from landing to a cupboard in 3rd bedroom or
loft. Mainly for the same reason as above.

OK. This gives you the choice of

a) combi boiler (can be DIY install with notification to Building
Control)

b) pressurised sealed HW cylinder (must be professionally installed)

c) heatbank. ((as (a))

These all involve using mains cold water, so the first thing to check
is that the mains flow at the kitchen tap is adequate. Time filling
a bucket and calculate. If it's less than 20 litres/min as a rule
of thumb then you will need to upgrade the pipework if need be to the
street or all of these will be disappointing.



Install new boiler in 1/ under stairs, 2/ in loft 3/ somewhere else. Though
exhaust of 1/ may interfere with subsequent garage updgrade at future date.


You can get around that. Quite a number of boilers can use pairs of
50mm high temperature plastic waste pipe which can be routed over long
distances to avoid this issue.


Finally new gas fire in lounge to replace back boiler.

These are the major considerations, how else do I choose Combi boiler or
stored water?

If you have the space for a cylinder or a heatbank (similar sizes)
then this will give far superior performance to a combi.




Current shower is balanced gravity fed which is newish in a new bathroom
that I don't want to upset - though I would like to improve shower
performance possibly in conjunction with raising water tank since I need to
move/replace it. Alternatively a combi boiler would give the needed extra
pressure or I could add a pump?

This would all depend on the cold mains and the performance of a
combi. You can get combis that will give 18 litres per minute of
shower temperature water.

You can use a pump together with a gravity tank but not on the mains.




As you can see I have so many variables it is hard to pin any of them down?
Where do I start?

Check the water supply before anything else. THis may dictate what
can and can't be economically done.


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Mon, 20 Sep 2004 17:19:43 GMT, "VisionSet"
wrote:

I'm about to start the last major upheaval in my house.
Replaceing the ancient back-boiler.
The whole project may involve most of these:

Move or remove Water tank. I don't want it where it is it is in the way
of a
subsequent minor loft conversion/over stairs mezzanine.

Move or remove water cylinder from landing to a cupboard in 3rd bedroom
or
loft. Mainly for the same reason as above.

OK. This gives you the choice of

a) combi boiler (can be DIY install with notification to Building
Control)

b) pressurised sealed HW cylinder (must be professionally installed)

c) heatbank. ((as (a))

and:

d) Two cheap combi's to give excellent flow rates and give CH zoning of
pone boiler doing upstairs and one downstairs. Cost effective.

These all involve using mains cold water, so the first thing to check
is that the mains flow at the kitchen tap is adequate. Time filling
a bucket and calculate. If it's less than 20 litres/min as a rule
of thumb then you will need to upgrade the pipework if need be to the
street or all of these will be disappointing.

Install new boiler in 1/ under stairs, 2/ in loft 3/ somewhere else.
Though
exhaust of 1/ may interfere with subsequent garage updgrade at future
date.


You can get around that. Quite a number of boilers can use pairs of
50mm high temperature plastic waste pipe which can be routed over long
distances to avoid this issue.


Finally new gas fire in lounge to replace back boiler.

These are the major considerations, how else do I choose Combi boiler or
stored water?

If you have the space for a cylinder or a heatbank (similar sizes)
then this will give far superior performance to a combi.

Depends on the hot water demands. An Alpha CB50 combi will give excellent
performance with using only one bathrrom. How many bathrooms?

Current shower is balanced gravity fed which is newish in a new bathroom
that I don't want to upset - though I would like to improve shower
performance possibly in conjunction with raising water tank since I need
to
move/replace it. Alternatively a combi boiler would give the needed
extra
pressure or I could add a pump?

This would all depend on the cold mains and the performance of a
combi. You can get combis that will give 18 litres per minute of
shower temperature water.

You can use a pump together with a gravity tank but not on the mains.




As you can see I have so many variables it is hard to pin any of them
down?
Where do I start?

Check the water supply before anything else. THis may dictate what
can and can't be economically done.


.andy

To email, substitute .nospam with .gl

"VisionSet" wrote in message
...
I'm about to start the last major upheaval in my house.
Replaceing the ancient back-boiler.
The whole project may involve most of these:

Move or remove Water tank. I don't want it where it is it is in the way of
a
subsequent minor loft conversion/over stairs mezzanine.

Move or remove water cylinder from landing to a cupboard in 3rd bedroom or
loft. Mainly for the same reason as above.

Install new boiler in 1/ under stairs, 2/ in loft 3/ somewhere else.
Though
exhaust of 1/ may interfere with subsequent garage updgrade at future
date.

Finally new gas fire in lounge to replace back boiler.

These are the major considerations, how else do I choose Combi boiler or
stored water?

Current shower is balanced gravity fed which is newish in a new bathroom
that I don't want to upset - though I would like to improve shower
performance possibly in conjunction with raising water tank since I need
to
move/replace it. Alternatively a combi boiler would give the needed extra
pressure or I could add a pump?

As you can see I have so many variables it is hard to pin any of them
down?
Where do I start?

Your requirements point to a mains water fed system with no tanks. Check
the mains pressure/flow. The Powermax may be suitable, with all being in
one box.

Some info:

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 a 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) Invinately Continuous/Unvented cylinder combi -

The Alpha CB50 is a combination of both having atwo 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 bunrer 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 N. 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, 20 Sep 2004 18:50:13 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Mon, 20 Sep 2004 17:19:43 GMT, "VisionSet"
wrote:

I'm about to start the last major upheaval in my house.
Replaceing the ancient back-boiler.
The whole project may involve most of these:

Move or remove Water tank. I don't want it where it is it is in the way
of a
subsequent minor loft conversion/over stairs mezzanine.

Move or remove water cylinder from landing to a cupboard in 3rd bedroom
or
loft. Mainly for the same reason as above.

OK. This gives you the choice of

a) combi boiler (can be DIY install with notification to Building
Control)

b) pressurised sealed HW cylinder (must be professionally installed)

c) heatbank. ((as (a))

and:

d) Two cheap combi's to give excellent flow rates and give CH zoning of
pone boiler doing upstairs and one downstairs. Cost effective.

I was covering the sensible solutions.


These all involve using mains cold water, so the first thing to check
is that the mains flow at the kitchen tap is adequate. Time filling
a bucket and calculate. If it's less than 20 litres/min as a rule
of thumb then you will need to upgrade the pipework if need be to the
street or all of these will be disappointing.

Install new boiler in 1/ under stairs, 2/ in loft 3/ somewhere else.
Though
exhaust of 1/ may interfere with subsequent garage updgrade at future
date.


You can get around that. Quite a number of boilers can use pairs of
50mm high temperature plastic waste pipe which can be routed over long
distances to avoid this issue.


Finally new gas fire in lounge to replace back boiler.

These are the major considerations, how else do I choose Combi boiler or
stored water?

If you have the space for a cylinder or a heatbank (similar sizes)
then this will give far superior performance to a combi.

Depends on the hot water demands. An Alpha CB50 combi will give excellent
performance with using only one bathrrom. How many bathrooms?

Mediochre would be a fairer description. This product delivers 50
litres of water at 60 degrees and then falls back to 11 lpm of 40
degree water.




..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Mon, 20 Sep 2004 18:50:13 +0100, "IMM" wrote:

"Andy Hall" wrote in message
.. .
On Mon, 20 Sep 2004 17:19:43 GMT, "VisionSet"
wrote:

I'm about to start the last major upheaval in my house.
Replaceing the ancient back-boiler.
The whole project may involve most of these:

Move or remove Water tank. I don't want it where it is it is in the
way
of a
subsequent minor loft conversion/over stairs mezzanine.

Move or remove water cylinder from landing to a cupboard in 3rd
bedroom
or
loft. Mainly for the same reason as above.

OK. This gives you the choice of

a) combi boiler (can be DIY install with notification to Building
Control)

b) pressurised sealed HW cylinder (must be professionally installed)

c) heatbank. ((as (a))

and:

d) Two cheap combi's to give excellent flow rates and give CH zoning of
pone boiler doing upstairs and one downstairs. Cost effective.

I was covering the sensible solutions.

But not well enough.

These all involve using mains cold water, so the first thing to check
is that the mains flow at the kitchen tap is adequate. Time filling
a bucket and calculate. If it's less than 20 litres/min as a rule
of thumb then you will need to upgrade the pipework if need be to the
street or all of these will be disappointing.

Install new boiler in 1/ under stairs, 2/ in loft 3/ somewhere else.
Though
exhaust of 1/ may interfere with subsequent garage updgrade at future
date.


You can get around that. Quite a number of boilers can use pairs of
50mm high temperature plastic waste pipe which can be routed over long
distances to avoid this issue.


Finally new gas fire in lounge to replace back boiler.

These are the major considerations, how else do I choose Combi boiler
or
stored water?

If you have the space for a cylinder or a heatbank (similar sizes)
then this will give far superior performance to a combi.

Depends on the hot water demands. An Alpha CB50 combi will give
excellent
performance with using only one bathrrom. How many bathrooms?

Mediochre would be a fairer description.

You have never seen one. Stop making things up.

This product delivers 50
litres of water at 60 degrees and then falls back to 11 lpm of 40
degree water.

Near 60 litres. Performance for one bath and shower is excellent. Well
worth considering.

On Mon, 20 Sep 2004 19:46:42 +0100, "IMM" wrote:



d) Two cheap combi's to give excellent flow rates and give CH zoning of
pone boiler doing upstairs and one downstairs. Cost effective.

I was covering the sensible solutions.

But not well enough.

Your last duo-combi solution needed funding of £2500 and an upgrade to
the gas supply from the street.




Depends on the hot water demands. An Alpha CB50 combi will give
excellent
performance with using only one bathrrom. How many bathrooms?

Mediochre would be a fairer description.

You have never seen one. Stop making things up.

There's nothing to make up. the spec. gives the entire story.



This product delivers 50
litres of water at 60 degrees and then falls back to 11 lpm of 40
degree water.

Near 60 litres. Performance for one bath and shower is excellent. Well
worth considering.

It's barely adequate for a drop in the bottom bath and 11lpm for a
shower is woefully inadequate.


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Mon, 20 Sep 2004 19:46:42 +0100, "IMM" wrote:



d) Two cheap combi's to give excellent flow rates and give CH zoning
of
pone boiler doing upstairs and one downstairs. Cost effective.

I was covering the sensible solutions.

But not well enough.

Your last duo-combi solution needed funding of £2500 and an upgrade to
the gas supply from the street.

Two W-B Juniors can provide excellent flow rates, back up as two boilers is
there and CH zones without any additional zones valves. Installation is
fully DIY and simple. Electrical work consists of a mains to each and one
wire to a clock programmer to each. It is also cost effective costing
around £1100. Cheaper if you negotiate as you are buying two.

Depends on the hot water demands. An Alpha CB50 combi will give
excellent
performance with using only one bathrrom. How many bathrooms?

Mediochre would be a fairer description.

You have never seen one. Stop making things up.

There's nothing to make up. the spec. gives the entire story.

Pitty you can't understand it.

This product delivers 50
litres of water at 60 degrees and then falls back to 11 lpm of 40
degree water.

Near 60 litres. Performance for one bath and shower is excellent. Well
worth considering.

It's barely adequate for a drop in the bottom bath and 11lpm for a
shower is woefully inadequate.

Yo are an idiot.

On Mon, 20 Sep 2004 20:03:13 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Mon, 20 Sep 2004 19:46:42 +0100, "IMM" wrote:



d) Two cheap combi's to give excellent flow rates and give CH zoning
of
pone boiler doing upstairs and one downstairs. Cost effective.

I was covering the sensible solutions.

But not well enough.

Your last duo-combi solution needed funding of £2500 and an upgrade to
the gas supply from the street.

Two W-B Juniors can provide excellent flow rates, back up as two boilers is
there and CH zones without any additional zones valves. Installation is
fully DIY and simple. Electrical work consists of a mains to each and one
wire to a clock programmer to each. It is also cost effective costing
around £1100. Cheaper if you negotiate as you are buying two.

These require 28kW apiece. If you want to run other appliances in
the house - e.g. cook something - a supply upgrade would be needed.



Depends on the hot water demands. An Alpha CB50 combi will give
excellent
performance with using only one bathrrom. How many bathrooms?

Mediochre would be a fairer description.

You have never seen one. Stop making things up.

There's nothing to make up. the spec. gives the entire story.

Pitty you can't understand it.

There's nothing to understand. It's a 57 litre store at 60 degrees
and a 28kW boiler. Nothing more that one needs to know to determine
exactly how it will behave.



This product delivers 50
litres of water at 60 degrees and then falls back to 11 lpm of 40
degree water.

Near 60 litres. Performance for one bath and shower is excellent. Well
worth considering.

It's barely adequate for a drop in the bottom bath and 11lpm for a
shower is woefully inadequate.

Yo are an idiot.

We did the sums on this last week.


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Mon, 20 Sep 2004 20:03:13 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Mon, 20 Sep 2004 19:46:42 +0100, "IMM" wrote:



d) Two cheap combi's to give excellent flow rates and give CH
zoning
of
pone boiler doing upstairs and one downstairs. Cost effective.

I was covering the sensible solutions.

But not well enough.

Your last duo-combi solution needed funding of £2500 and an upgrade to
the gas supply from the street.

Depends on what flowrate you want.

Two W-B Juniors can provide excellent flow rates, back up as two boilers
is
there and CH zones without any additional zones valves. Installation is
fully DIY and simple. Electrical work consists of a mains to each and
one
wire to a clock programmer to each. It is also cost effective costing
around £1100. Cheaper if you negotiate as you are buying two.

These require 28kW apiece.

They have 24 and 28

If you want to run other appliances in
the house - e.g. cook something - a
supply upgrade would be needed.

Depends on the hot water demands. An Alpha CB50 combi will give
excellent
performance with using only one bathrrom. How many bathrooms?

Mediochre would be a fairer description.

You have never seen one. Stop making things up.

There's nothing to make up. the spec. gives the entire story.

Pitty you can't understand it.

There's nothing to understand. It's a 57 litre store at 60 degrees
and a 28kW boiler. Nothing more that one needs to know to determine
exactly how it will behave.

You still haven't got it.

This product delivers 50
litres of water at 60 degrees and then falls back to 11 lpm of 40
degree water.

Near 60 litres. Performance for one bath and shower is excellent.
Well
worth considering.

It's barely adequate for a drop in the bottom bath and 11lpm for a
shower is woefully inadequate.

You are an idiot.

We did the sums on this last week.

We? You you mean. You are still an idiot.

On Mon, 20 Sep 2004 20:31:12 +0100, "IMM" wrote:



Two W-B Juniors can provide excellent flow rates, back up as two boilers
is
there and CH zones without any additional zones valves. Installation is
fully DIY and simple. Electrical work consists of a mains to each and
one
wire to a clock programmer to each. It is also cost effective costing
around £1100. Cheaper if you negotiate as you are buying two.

These require 28kW apiece.

They have 24 and 28

Even at 48kW there's barely enough left for a cooker.



You have never seen one. Stop making things up.

There's nothing to make up. the spec. gives the entire story.

Pitty you can't understand it.

There's nothing to understand. It's a 57 litre store at 60 degrees
and a 28kW boiler. Nothing more that one needs to know to determine
exactly how it will behave.

You still haven't got it.

There's nothing to get.



This product delivers 50
litres of water at 60 degrees and then falls back to 11 lpm of 40
degree water.

Near 60 litres. Performance for one bath and shower is excellent.
Well
worth considering.

It's barely adequate for a drop in the bottom bath and 11lpm for a
shower is woefully inadequate.

You are an idiot.

We did the sums on this last week.

We? You you mean. You are still an idiot.

Sorry I forgot. You had problems with multiplication and division and
understanding the formula for mixing water of two different
temperatures together.






..andy

To email, substitute .nospam with .gl

"VisionSet" wrote in message
...
I'm about to start the last major upheaval in my house.
Replaceing the ancient back-boiler.
....

I'll add a little more detail maybe you two can agree on something ;-)

House is 3-bed semi. 1 bathroom/toilet (ie one room). 6 rads + 1 teeny
one.

So the upshot is that nowadays combis are worth considering?
I'm think that when I had a look 6 years back that wasn't so much the case.

I am going to do all the work myself though get a corgi chap in for final
gas hook up to maintain boiler guarantee - that is the case is it not?

mains flow is 19.8 l/min - I guess that is okay.

One issue that concerns me is reliability of a combi - my back boiler gets
next to no service and is 30 years old - glowworm model I'm finding it
excellent value! okay so it isn't quite the efficient boiler of today. Have
combis got more reliable of late?

If I put the boiler under the stairs (prefered location) available dims are
1240mm high x 770mm wide (width better alot less) depth slim as possible but
no actual restriction.

Hollow floors eases plumbing. All existing pipework is copper. 15mm
throughout except 22mm joins upstairs to downstairs rads. Shower is gravity
fed from same loft tank with very little head of water - perhaps 3ft max
shower head tank water level (full). Had a just tollerable dribble for too
long now :-( With a Trevie ceramic mixer valve.

There is the usual heating top up tank - Do any new real candidate systems
still need this?

Can I put the whole shooting match in the loft?
Loft is too low for a full loft conversion so I might as well use it for
something - I think the one thing that I don't like about that my perception
of heat waste from the cylinder and boiler - I kind of liked the idea of
putting them somewhere I would benefit from any inefficiencies. However I
rather suspect these days those innefficiencies may well be negligble - or
at least unbenefittable from.

If it is ill advised to put the whole lot in the loft - which bits are a
good idea to put up there? House is 1930's with the hefty purlins and very
low since the rafter line is part in 1st floor. So height of any apparatus
is a factor.

Andy - do you see away to ditch the tanks without going combi? Is that
pressurised system?

I need to do some reading definitions of these systems - any links?

--
Mike W

"VisionSet" wrote in message
...


Hollow floors eases plumbing. All existing pipework is copper. 15mm
throughout except 22mm joins upstairs to downstairs rads.

Oh and 22mm H&C to bath - gravity fed

--
Mike W

"VisionSet" wrote in message
...

"VisionSet" wrote in message
...
I'm about to start the last major upheaval in my house.
Replaceing the ancient back-boiler.
...

I'll add a little more detail maybe you two can agree on something ;-)

House is 3-bed semi. 1 bathroom/toilet (ie one room). 6 rads + 1 teeny
one.

So the upshot is that nowadays combis are worth considering?
I'm think that when I had a look 6 years back that wasn't so much the
case.

I am going to do all the work myself though get a corgi chap in for final
gas hook up to maintain boiler guarantee - that is the case is it not?

mains flow is 19.8 l/min - I guess that is okay.

That is quite low. and just about acceptable for a low flowrate combi. Look
at getting the mains from the road updated.

One issue that concerns me is reliability of a combi - my back boiler gets
next to no service and is 30 years old - glowworm model I'm finding it
excellent value! okay so it isn't quite the efficient boiler of today.
Have
combis got more reliable of late?

In general they were never unreliable. Some models were crap, but so are
some cars, washing machines, etc.

If I put the boiler under the stairs
(prefered location) available dims are
1240mm high x 770mm wide (width better
alot less) depth slim as possible but
no actual restriction.

Hollow floors eases plumbing. All existing pipework is copper. 15mm
throughout except 22mm joins upstairs to downstairs rads. Shower is
gravity
fed from same loft tank with very little head of water - perhaps 3ft max
shower head tank water level (full). Had a just tollerable dribble for
too
long now :-( With a Trevie ceramic mixer valve.

There is the usual heating top up tank - Do any new real candidate systems
still need this?

Can I put the whole shooting match in the loft?

Yep.

Loft is too low for a full loft conversion so I might as well use it for
something - I think the one thing that I don't like about that my
perception
of heat waste from the cylinder and boiler - I kind of liked the idea of
putting them somewhere I would benefit from any inefficiencies. However I
rather suspect these days those innefficiencies may well be negligble - or
at least unbenefittable from.

If it is ill advised to put the whole lot in the loft - which bits are a
good idea to put up there? House is 1930's with the hefty purlins and
very
low since the rafter line is part in 1st floor. So height of any
apparatus
is a factor.

Andy - do you see away to ditch the tanks without going combi? Is that
pressurised system?

A heat bank. Look at a Potterton Powermax (boiler and cylinder all in one
box). It can go in the loft.

An Alpha CB50 combi will be fine for you. 19 litres/min and drops to 11
litres/min when internal store exhausted. You will fill a bath reasonably
quickly and have good showers.

I need to do some reading definitions
of these systems - any links?

http://www.heatweb.com Good explanation.

Look at my recent post, 20/9/2004 on combi boiler explanations.

On Mon, 20 Sep 2004 22:44:33 GMT, "VisionSet"
wrote:


"VisionSet" wrote in message
...
I'm about to start the last major upheaval in my house.
Replaceing the ancient back-boiler.
...

I'll add a little more detail maybe you two can agree on something ;-)

House is 3-bed semi. 1 bathroom/toilet (ie one room). 6 rads + 1 teeny
one.

So the upshot is that nowadays combis are worth considering?
I'm think that when I had a look 6 years back that wasn't so much the case.

I am going to do all the work myself though get a corgi chap in for final
gas hook up to maintain boiler guarantee - that is the case is it not?

mains flow is 19.8 l/min - I guess that is okay.


Should be fine.


One issue that concerns me is reliability of a combi - my back boiler gets
next to no service and is 30 years old - glowworm model I'm finding it
excellent value! okay so it isn't quite the efficient boiler of today. Have
combis got more reliable of late?

I'd defer to Ed Sirett, John Stumbles or John Boilerdoc on that one
since they have regular contact, and raden because his company fixes
boards and supplies spares.

Like anything if you buy a decent one then results should be good.
Generally boilers of German origin or design seem to fare well.


If I put the boiler under the stairs (prefered location) available dims are
1240mm high x 770mm wide (width better alot less) depth slim as possible but
no actual restriction.

This would give you a fair choice. Most should fit that.



Hollow floors eases plumbing. All existing pipework is copper. 15mm
throughout except 22mm joins upstairs to downstairs rads. Shower is gravity
fed from same loft tank with very little head of water - perhaps 3ft max
shower head tank water level (full). Had a just tollerable dribble for too
long now :-( With a Trevie ceramic mixer valve.

There is the usual heating top up tank - Do any new real candidate systems
still need this?

Most boilers will run a pressurised primary.

You can DIY install a combi or a combi with indirect heatbank - i.e.
where the coil is in the primary circuit. This could be interesting
to do if you had a small combi relatively close to the kitchen and
used its directly produced water downstairs and then heated a cylinder
upstairs for the bathroom. In effect, you heat the cylinder by using
the CH part of the combi with the normal motorised valves as though
you were using a conventional boiler.

In a heatbank application you can buy the complete package, and
typically the heatbank cylinder is run vented. They can come with a
feed tank for this integral with the cylinder. You would heat the
heatbank via a coil and then the bulk (tertiary) water in the
heatbank is pumped through a plate heat exchanger to heat the DHW.
This arrangement can be DIYed because there is no large bulk of water
at mains pressure.

You could even have this arrangement with the CH vented and a direct
heatbank, but then the top of the heatbank must be above the highest
radiator. With a pressurised primary you do have more flexibility.


Can I put the whole shooting match in the loft?
Loft is too low for a full loft conversion so I might as well use it for
something - I think the one thing that I don't like about that my perception
of heat waste from the cylinder and boiler - I kind of liked the idea of
putting them somewhere I would benefit from any inefficiencies. However I
rather suspect these days those innefficiencies may well be negligble - or
at least unbenefittable from.

Yes you can. If you go for a decent condensing boiler, they run very
efficiently and you can also have the cylinder foamed to 100mm instead
of the typical 50mm.

You do have to board the relevant part of the loft and provide a rail.
THis is a Health and Safety requirement so that gas fitters can work
safely to service the boiler.




If it is ill advised to put the whole lot in the loft - which bits are a
good idea to put up there? House is 1930's with the hefty purlins and very
low since the rafter line is part in 1st floor. So height of any apparatus
is a factor.

No reason why not if it will fit. Positioning the cylinder where
the roof tank was should be OK, otherwise locate over a loadbearing
wall.






Andy - do you see away to ditch the tanks without going combi? Is that
pressurised system?

Yes you can do that.

One option are a heatbank as described. Albion do them as one
example. You can DIY this because the cylinder water is not
pressurised.

The other is a sealed pressurised cylinder.

This is not a DIY job as the Building Regulations require that a
trained fitter installs them. They are also supposed to have annual
maintenance under the terms of some insurance policies.



..andy

To email, substitute .nospam with .gl

On Tue, 21 Sep 2004 00:02:59 +0100, "IMM" wrote:



A heat bank. Look at a Potterton Powermax (boiler and cylinder all in one
box). It can go in the loft.

Watch the weight.



An Alpha CB50 combi will be fine for you. 19 litres/min and drops to 11
litres/min when internal store exhausted. You will fill a bath reasonably
quickly and have good showers.

On this I differ and presented the calculations as to why last week.


I need to do some reading definitions
of these systems - any links?

http://www.heatweb.com Good explanation.


Yes, although the claims on some of the products miss out vital
information like the temperature of the cold water used in tests.

It is highly advisable to do sanity checks on what is physically
possible rather than relying on marketware.


..andy

To email, substitute .nospam with .gl

In message , VisionSet
writes

"VisionSet" wrote in message
...
I'm about to start the last major upheaval in my house.
Replaceing the ancient back-boiler.
...

I'll add a little more detail maybe you two can agree on something ;-)

House is 3-bed semi. 1 bathroom/toilet (ie one room). 6 rads + 1 teeny
one.

So the upshot is that nowadays combis are worth considering?
I'm think that when I had a look 6 years back that wasn't so much the case.

I am going to do all the work myself though get a corgi chap in for final
gas hook up to maintain boiler guarantee - that is the case is it not?

mains flow is 19.8 l/min - I guess that is okay.


Hi Mike,

I too have followed some of the to-ing and fro-ing over combis versus
traditional boiler and tanks. I can only give you *my experience* in
this matter as a user.

We just replaced a fairly standard boiler/header tanks/immersion - baxi
back boiler with a Halstead Ace High (combi).

There are a lot of figures quoted on here about flow rates, well this is
a bog standard combi quoted at 35 degree rise at 13 l/pm.

It's quite simply the best shower I've had. Lots of water, lots of heat.
The boiler DHW temperature control is set to about two thirds and the
mixer valve on the shower at a little over 50% hot. I have never yet
fully extended the shower lever for maximum flow. I *assume* therefore,
that the 13 l/pm is more than enough for what I expect of a shower.

Because of other threads on here, I specifically asked the girlfriend
how long it takes her to fill the bath. She reckoned 5 or 10 minutes.
Whether it is actually longer or shorter than 5/10 mins, I don't know.
The fact that she was so non-chalant about it makes me assume she's
never thought about it, and so I would guess it is not an issue for her.

(I have never measured the volume of the bath, and for other readers
here - NO I am not going to. It looks like a normal bath to me).

FYI, the house is a 3 bed semi, 1 bathroom & 1 toilet. If I'm in the
shower and the hot tap in the kitchen is turned on, it is noticeable. It
doesn't bother me at all, but it yes, it is noticeable.

One issue that concerns me is reliability of a combi - my back boiler gets
next to no service and is 30 years old - glowworm model I'm finding it
excellent value! okay so it isn't quite the efficient boiler of today. Have
combis got more reliable of late?

No idea, wouldn't know if they ever were/were not reliable to start
with.

You can get the Ace High branded as Wickes own model (identical boiler
from the same factory but with a different badge) for 500 ish quid. At
that price, I don't think reliability is the biggest issue.


If I put the boiler under the stairs (prefered location) available dims are
1240mm high x 770mm wide (width better alot less) depth slim as possible but
no actual restriction.

I believe most manufacturers publish the physical installation
characteristics, certainly Halstead do.

Can I put the whole shooting match in the loft?
Loft is too low for a full loft conversion so I might as well use it for
something - I think the one thing that I don't like about that my perception
of heat waste from the cylinder and boiler - I kind of liked the idea of
putting them somewhere I would benefit from any inefficiencies. However I
rather suspect these days those innefficiencies may well be negligble - or
at least unbenefittable from.

One of the things I love about the combi is the space we have saved -
and even if I found something which bugged me about it, I doubt it would
ever out-do the advantage of the extra space. We used to have 2 airing
cupboards basically taken over by heating, one for the immersion and one
for the pumps and other various gubbins. (This latter cupboard was not
particularly well done and was actually a source of amusement for any
plumber who ever saw it).

On top of that, the room with the back boiler which *had* to have the
gas fire front + hearth etc etc, and of course the various tanks in the
loft.

That is now all gone. The space saved in the loft is quite remarkable
(so much so that I've held off finishing decorating upstairs in order to
have a staircase put into the loft as a starting point for a full loft
conversion) and downstairs, we now have a full height 3ft wide by 3ft
deep cupboard to use as we wish.

If it is ill advised to put the whole lot in the loft - which bits are a
good idea to put up there? House is 1930's with the hefty purlins and very
low since the rafter line is part in 1st floor. So height of any apparatus
is a factor.

This particular combi includes frost protection, pump cycling etc. For
this reason I imagine you could site it virtually anywhere - the main
constraint being the flue routing.


Andy - do you see away to ditch the tanks without going combi? Is that
pressurised system?

I need to do some reading definitions of these systems - any links?


Those are just my thoughts as a user, having in the past three months
gone from a traditional system to a combi. I wouldn't go back, I love
it.

Maybe you should ask again in the middle of winter, when apparently the
incoming water supply is that much colder - personally I don't see this
as a problem, but won't know until the depths of winter. I assume and
expect that the combi will just carry on as normal and I'll still have a
good shower.

[What now follows is a blow by blow account of what other boiler I could
have had tuppence cheaper, with a higher flow rate, how it is useless in
the event of a power cut, how I could have had two of them instead of
one and how the [Toytown/Tinseltown*] [Combi/Trad*] model [10/40*] is
better because it uses a 4mm metric thread on the case screws instead of
5mm.]. (*Delete as appropriate).

All the best :-)
Bill

"invalid" wrote in message
...
In message , VisionSet
writes

"VisionSet" wrote in message
...
I'm about to start the last major upheaval in my house.
Replaceing the ancient back-boiler.
...

I'll add a little more detail maybe you two can agree on something ;-)

House is 3-bed semi. 1 bathroom/toilet (ie one room). 6 rads + 1 teeny
one.

So the upshot is that nowadays combis are worth considering?
I'm think that when I had a look 6 years back that wasn't so much the
case.

I am going to do all the work myself though get a corgi chap in for final
gas hook up to maintain boiler guarantee - that is the case is it not?

mains flow is 19.8 l/min - I guess that is okay.


Hi Mike,

I too have followed some of the to-ing and fro-ing over combis versus
traditional boiler and tanks. I can only give you *my experience* in
this matter as a user.

We just replaced a fairly standard boiler/header tanks/immersion - baxi
back boiler with a Halstead Ace High (combi).

Good boiler. The Wickes Combi 102 with 2 yr guaranteee. I fitted one about
2.5 years ago and it works very well. It is a doddle to fit. For a 13
litres/min combi it is about the cheapest around from Wickes. They do a
smaller one, the Combi 80. Service is good from Halstead.

There are a lot of figures quoted on here about flow rates, well this is
a bog standard combi quoted at 35 degree rise at 13 l/pm.

It's quite simply the best shower I've had. Lots of water, lots of heat.
The boiler DHW temperature control is set to about two thirds and the
mixer valve on the shower at a little over 50% hot. I have never yet
fully extended the shower lever for maximum flow. I *assume* therefore,
that the 13 l/pm is more than enough for what I expect of a shower.

Because of other threads on here, I specifically asked the girlfriend
how long it takes her to fill the bath. She reckoned 5 or 10 minutes.
Whether it is actually longer or shorter than 5/10 mins, I don't know.
The fact that she was so non-chalant about it makes me assume she's
never thought about it, and so I would guess it is not an issue for her.

Many people fill the bath to a level with they can just sit in, which will
fill pretty quickly, and let the tap run as they are in the bath.

If bath fills are a problem, a combi such as the Alpha CB50 will be
absolutely excellent.

(I have never measured the volume of the bath, and for other readers
here - NO I am not going to. It looks like a normal bath to me).

FYI, the house is a 3 bed semi, 1 bathroom & 1 toilet. If I'm in the
shower and the hot tap in the kitchen is turned on, it is noticeable. It
doesn't bother me at all, but it yes, it is noticeable.

It is best to put an in-line isolating valve on the tap and throttle it
back. Cost about £1.50 from Wickes. You don't need firehose flow and
pressures from the kitchen tap, or any tap for that matter, only the shower.

You can also fit before the shower mixer an equalizing valve. Both hot and
cold run through it. It balances the pressures to both pipes, avoiding any
severe pressure drop problems if a tap a tap is turned on. They are
available from B&Q Warehouse for about £20.

If it is ill advised to put the whole lot in the loft - which bits are a
good idea to put up there?

No problem. I have a similar size house to you. 3 bed, 1 bath.

I have a Worcester Bosch Greenstar 28HE in the loft feeding a DPS Pandora
heat bank, also in the loft. No additional cold tanks at all. Hot water is
mains pressure, with a flow rate of 40 litres per minute @ 60C.

Basically, both a system like this and a combi are going to provide
absolutely superb showers, as they both provide mains pressure and the
shower head or valve will limit flow rate to below the capacity of the
boiler.

The main differences between the systems will be on bath filling performance
or on having multiple showers. If you have/do neither regularly, then the
combi will save you money.

Note that if you install in the loft, there may be additional costs, most of
which didn't apply to me because they were already present.

1. Loft must be boarded.
2. Loft must have lighting.
3. Loft must have mounted loft ladder (can fold away).
4. Hatch must have guard rails.
5. You need a slightly more expensive vertical flue.
6. You need longer pipe and electrical control runs.

Christian.

On Tue, 21 Sep 2004 00:53:21 GMT, invalid wrote:


Maybe you should ask again in the middle of winter, when apparently the
incoming water supply is that much colder - personally I don't see this
as a problem, but won't know until the depths of winter. I assume and
expect that the combi will just carry on as normal and I'll still have a
good shower.


Right now the mains water temperature is around the 15 degree area,
so for a shower, the temperature has to be raised by 25 degrees.

In winter it will fall to 5-8 degrees, so the temperature will have to
be raised by 35 degrees.

The flow rate will fall by 40%.



..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Tue, 21 Sep 2004 00:53:21 GMT, invalid wrote:


Maybe you should ask again in the middle of winter, when apparently the
incoming water supply is that much colder - personally I don't see this
as a problem, but won't know until the depths of winter. I assume and
expect that the combi will just carry on as normal and I'll still have a
good shower.


Right now the mains water temperature is around the 15 degree area,
so for a shower, the temperature has to be raised by 25 degrees.

In winter it will fall to 5-8 degrees, so the temperature will have to
be raised by 35 degrees.

The flow rate will fall by 40%.

He doesn't use it all anyway, so will still have a great shower.

In article ,
invalid wrote:
We just replaced a fairly standard boiler/header tanks/immersion - baxi
back boiler with a Halstead Ace High (combi).

There are a lot of figures quoted on here about flow rates, well this is
a bog standard combi quoted at 35 degree rise at 13 l/pm.

It's quite simply the best shower I've had. Lots of water, lots of heat.

Then your storage system was incompetently designed, or the shower not
suitable. The flow rate from that is only limited by the head and size of
pipes - not how quickly it can heat the water.

--
*I just got lost in thought. It was unfamiliar territory.

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

On Tue, 21 Sep 2004 10:16:56 +0100, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Tue, 21 Sep 2004 00:53:21 GMT, invalid wrote:


Maybe you should ask again in the middle of winter, when apparently the
incoming water supply is that much colder - personally I don't see this
as a problem, but won't know until the depths of winter. I assume and
expect that the combi will just carry on as normal and I'll still have a
good shower.


Right now the mains water temperature is around the 15 degree area,
so for a shower, the temperature has to be raised by 25 degrees.

In winter it will fall to 5-8 degrees, so the temperature will have to
be raised by 35 degrees.

The flow rate will fall by 40%.

He doesn't use it all anyway, so will still have a great shower.

Mmmm.


..andy

To email, substitute .nospam with .gl

"IMM" wrote in message ...
"Andy Hall" wrote in message
...
On Mon, 20 Sep 2004 19:46:42 +0100, "IMM" wrote:
It's barely adequate for a drop in the bottom bath and 11lpm for a
shower is woefully inadequate.

Yo are an idiot.

As soon as you resort to ad hominem attacks (as you always do), you
have lost the argument.

MBQ

"MBQ" wrote in message
om...
"IMM" wrote in message
...
"Andy Hall" wrote in message
...
On Mon, 20 Sep 2004 19:46:42 +0100, "IMM" wrote:
It's barely adequate for a drop in the bottom bath and 11lpm for a
shower is woefully inadequate.

Yo are an idiot.

As soon as you resort to ad hominem attacks (as you always do), you
have lost the argument.

There was not an argument. Just me attempting educate the uneducated. I
don't argue with him, I tell him.

Of course I should have mentioned that cost is a factor.

Those thermal stores look a great idea but they look pricey.

I suppose a combi is the cheapest option, but I have a feeling it won't be
up to the job, simultaneous use, bath filling. I only have 3 bed semi - but
for resale and our own use, perhaps combi isn't the way to go.

I guess if I go for anthing other than combi and consdidering I'm doing the
whole system, except rads & pipework, I should not replace with old hat tank
& cylinder. I suppose I can get a decent regular boiler for not much, is
condensing worth it?

What are those German boiler manufacturers alluded to?

What sort of cost am I looking at for boiler, heat store, controllers?

--
Mike W

What sort of cost am I looking at for boiler, heat store, controllers?

For good quality components, you're talking between 1500-2000, including all
controls, zone valves, condensing boiler, heat bank, programmer,
programmable room stat. It could be done cheaper, if you intend to use less
regarded brands, however the above will get you something decent, like a
Worcester Bosch Greenstar and DPS heatbank.

Basically a stored energy mains pressure hot water system will cost you
twice that of an equivalent quality instantaneous combi in parts, although
the time spent fitting will have less of a difference and hot water
performance will be in a different league.

Christian.

On Tue, 21 Sep 2004 14:34:03 GMT, "VisionSet"
wrote:

Of course I should have mentioned that cost is a factor.

Those thermal stores look a great idea but they look pricey.

I suppose a combi is the cheapest option, but I have a feeling it won't be
up to the job, simultaneous use, bath filling. I only have 3 bed semi - but
for resale and our own use, perhaps combi isn't the way to go.

If you are looking at short term sale then it doesn't matter because
most buyers won't know the difference - especially if you sell in the
spring to autumn when the water is warm.


I guess if I go for anthing other than combi and consdidering I'm doing the
whole system, except rads & pipework, I should not replace with old hat tank
& cylinder. I suppose I can get a decent regular boiler for not much, is
condensing worth it?

Definitely. I have made savings of between 25 and 30% compared with
my previous conventional boiler.



What are those German boiler manufacturers alluded to?

Worcester Bosch, Vaillant, Viessmann, MAN,......


What sort of cost am I looking at for boiler, heat store, controllers?

For the lot, something in the £1500-2000 range if you want decent
ones.



..andy

To email, substitute .nospam with .gl

In article ,
Christian McArdle wrote:
Basically a stored energy mains pressure hot water system will cost you
twice that of an equivalent quality instantaneous combi in parts,
although the time spent fitting will have less of a difference and hot
water performance will be in a different league.

Of course many don't start from scratch and may already have a storage
system much of which can be re-used.

--
*Fax is stronger than fiction *

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

"VisionSet" wrote in message
...
Of course I should have mentioned that cost is a factor.

Those thermal stores look a great
idea but they look pricey.

I suppose a combi is the cheapest option,
but I have a feeling it won't be
up to the job, simultaneous use, bath filling.
I only have 3 bed semi - but for resale and
our own use, perhaps combi isn't the way to go.

The Alpha CB50 will do you fine. The flowrate is excellent and will fill a
bath quicko and give excellent showers. Take no notice of amateur
know-it-alls, a large flow combi is ideal for you. If I was you that is
what I would go for.

It is also a very cost effective way to go, also saving valuable space in
your semi.

"IMM" wrote in message
...

"VisionSet" wrote in message
...
Of course I should have mentioned that cost is a factor.

Those thermal stores look a great
idea but they look pricey.

I suppose a combi is the cheapest option,
but I have a feeling it won't be
up to the job, simultaneous use, bath filling.
I only have 3 bed semi - but for resale and
our own use, perhaps combi isn't the way to go.

The Alpha CB50 will do you fine. The flowrate is excellent and will fill a
bath quicko and give excellent showers. Take no notice of amateur
know-it-alls, a large flow combi is ideal for you. If I was you that is
what I would go for.

It is also a very cost effective way to go, also saving valuable space in
your semi.

Look at:
http://www.alpha-boilers.co.uk/products/CB50.html

The Worcester Bosch Greenstar 40kW condensing combi is good too.

On Tue, 21 Sep 2004 17:26:14 +0100, "IMM" wrote:


"VisionSet" wrote in message
...
Of course I should have mentioned that cost is a factor.

Those thermal stores look a great
idea but they look pricey.

I suppose a combi is the cheapest option,
but I have a feeling it won't be
up to the job, simultaneous use, bath filling.
I only have 3 bed semi - but for resale and
our own use, perhaps combi isn't the way to go.

The Alpha CB50 will do you fine. The flowrate is excellent and will fill a
bath quicko and give excellent showers.

The marketing literature is full of claims which do not look nearly so
good when the technical data is checked.

- The flow rate is specified as 18lpm but this is only until the 57
litre store is empty. This equates to a total of 90 litres mixed
with cold water for a bath (which is not enough)
After that it will be 11lpm because the output to water is 28kW.

- The marketing information claims that the vessel is fully recovered
in 3.5 minutes. The data sheet says to 70% of capacity and with the
boiler already running.

Take no notice of amateur
know-it-alls,

Quite.

a large flow combi is ideal for you.

Except that this isn't one.

If I was you that is
what I would go for.

It is also a very cost effective way to go, also saving valuable space in
your semi.


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Tue, 21 Sep 2004 17:26:14 +0100, "IMM" wrote:


"VisionSet" wrote in message
...
Of course I should have mentioned that cost is a factor.

Those thermal stores look a great
idea but they look pricey.

I suppose a combi is the cheapest option,
but I have a feeling it won't be
up to the job, simultaneous use, bath filling.
I only have 3 bed semi - but for resale and
our own use, perhaps combi isn't the way to go.

The Alpha CB50 will do you fine.
The flowrate is excellent and will fill a
bath quicko and give excellent showers.

The marketing literature is full of claims
which do not look nearly so
good when the technical data is checked.

- The flow rate is specified as 18lpm but this is only until the 57
litre store is empty. This equates to a total of 90 litres mixed
with cold water for a bath (which is not enough)
After that it will be 11lpm because the output to water is 28kW.

Alpha say:
"When the store is fully charged an equivalent domestic hot water output of
50kW gives a flow rate of 18 litres per minute at 60°C, enough to fill an
average bath in about 3.5 minutes.

If the store did run out 11 litres/min will still top the bath up. So, an
average bath can be filled quicko. Showers will be high pressure.

Take no notice of amateur
know-it-alls,

Quite.

a large flow combi is ideal for you.

Except that this isn't one.

That's if you have seen large flowrate combi. This man is wanting info to
make a decision on a water system for his home. For his situation and needs
the Alpha and Greenstar 40kW are ideal.

You acting the goat doesn't help at all.

If I was you that is
what I would go for.

It is also a very cost effective way
to go, also saving valuable space in
your semi.

In article ,
IMM wrote:
Take no notice of amateur know-it-alls, a large flow combi is ideal for
you.

The standard answer from a fool regardless of the question or requirements.

If I was you that is what I would go for.

Of course. You can only cope with simple installations. Hence the one
answer to everything.

--
*Heart attacks... God's revenge for eating his animal friends

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

"Dave Plowman (News)" wrote in message
...
In article ,
Christian McArdle wrote:
Basically a stored energy mains pressure hot water system will cost you
twice that of an equivalent quality instantaneous combi in parts,
although the time spent fitting will have less of a difference and hot
water performance will be in a different league.

Of course many don't start from scratch and may already have a storage
system much of which can be re-used.


Maybe I'm overlooking something but it seems the prices are almost
comparable

worcester bosch 40kw combi £1350

worcester bosch 28 HE system boiler & pandora heat bank £1500

I know you can get a cheaper combi - but to try and reduce performance
problem...

This at present is leaning me towards the latter

--
Mike W

On Tue, 21 Sep 2004 18:00:36 +0100, "IMM" wrote:



Alpha say:
"When the store is fully charged an equivalent domestic hot water output of
50kW gives a flow rate of 18 litres per minute at 60°C, enough to fill an
average bath in about 3.5 minutes.

This is bull**** marketing like music power on amplifiers.

It is not an equivalent power output of 50kW because it lasts for a
short time.

Plugging the numbers in, the boiler will deliver 90 litres of water,
mixed with cold at bath temperature. It will take longer than 3.5
minutes to do it as well.

After that, the remaining 60 litres of water needed for the bath will
be at 11lpm.


If the store did run out 11 litres/min will still top the bath up. So, an
average bath can be filled quicko. Showers will be high pressure.

Take no notice of amateur
know-it-alls,

Quite.

a large flow combi is ideal for you.

Except that this isn't one.

That's if you have seen large flowrate combi. This man is wanting info to
make a decision on a water system for his home. For his situation and needs
the Alpha and Greenstar 40kW are ideal.

They are completely different products.

The Greenstar could be considered to be "high" flow rate if you
consider 16lpm at 40 degrees to be high flow rate. A storage system
can outperform that in every way.

The Alpha has a tiny store and a standard sized burner and is very
limited as a result. The marketing information that you have read is
not borne out in the technical specs.





..andy

To email, substitute .nospam with .gl

"VisionSet" wrote in message
...

"Dave Plowman (News)" wrote in message
...
In article ,
Christian McArdle wrote:
Basically a stored energy mains pressure hot water system will cost
you
twice that of an equivalent quality instantaneous combi in parts,
although the time spent fitting will have less of a difference and hot
water performance will be in a different league.

Of course many don't start from scratch and may already have a storage
system much of which can be re-used.


Maybe I'm overlooking something but it seems the prices are almost
comparable

worcester bosch 40kw combi £1350

worcester bosch 28 HE system boiler & pandora heat bank £1500

I know you can get a cheaper combi - but to try and reduce performance
problem...

This at present is leaning me towards the latter

An alpha CB50 is approx 1K. One box , on the wall. and performance is all
you need.

"Andy Hall" wrote in message
...
On Tue, 21 Sep 2004 18:00:36 +0100, "IMM" wrote:



Alpha say:
"When the store is fully charged an equivalent domestic hot water output
of
50kW gives a flow rate of 18 litres per minute at 60°C, enough to fill an
average bath in about 3.5 minutes.

snip tripe

"Dave Plowman (News)" wrote in
:


It's quite simply the best shower I've had. Lots of water, lots of
heat.

Then your storage system was incompetently designed, or the shower not
suitable. The flow rate from that is only limited by the head and size
of pipes

Not even by that, with a booster pump

mike

In article ,
IMM wrote:
An alpha CB50 is approx 1K. One box , on the wall. and performance is
all you need.

Correction. All *you* may need. Not the same thing - by a long chalk.

--
*Strip mining prevents forest fires.

Dave Plowman London SW
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