Hi All,

I am still deciding on the best replacement heating system and the DHW flow rate is quite important. Whilst browsing many websites I came across the Albion Water Heaters http://www.albion-online.co.uk site and in particular the Superduty tanks that provide a very quick recharge. And the site has a schematic for a system using this tank with a combi. I have attached this diagram.

I would really like to have your views on this solution, as if it is ok, it could provide me an answer and looks pretty easy to install, although I am not sure what is different between this and a "conventional" system!

Thanks

Andy

On Sun, 23 Jan 2005 21:38:05 +0000, AndyHingston
wrote:


Hi All,

I am still deciding on the best replacement heating system and the DHW
flow rate is quite important. Whilst browsing many websites I came
across the Albion Water Heaters http://www.albion-online.co.uk site and
in particular the Superduty tanks that provide a very quick recharge.
And the site has a schematic for a system using this tank with a combi.
I have attached this diagram.

I would really like to have your views on this solution, as if it is
ok, it could provide me an answer and looks pretty easy to install,
although I am not sure what is different between this and a
"conventional" system!




It's basically a conventional storage system with the CH part of the
combi used to heat the radiators or the cylinder. Not an
unreasonable solution. Flow rate for the bath can be what you want it
to be if you have a large enough tank and cylinder and you do some of
the pipework from tank to cylinder to tap in 28mm.

However, watch out for the wording.

The 45 litre CF45 will contain water at 60 degrees, but the amount
stored could well be too little for filling a bath. The heat
exchanger is quite efficient because it has a large surface area, but
will be limited by what the boiler can produce.

The 80 litre model would be a far safer choice and is not
substantially larger in terms of cupboard space requirements.

The combi part of the set up could feed a shower or kitchen taps and
in effect the bath would not impact or be impacted.




--

..andy

To email, substitute .nospam with .gl

"AndyHingston" wrote in message
...

Hi All,

I am still deciding on the best replacement heating system and the DHW
flow rate is quite important. Whilst browsing many websites I came
across the Albion Water Heaters http://www.albion-online.co.uk site and
in particular the Superduty tanks that provide a very quick recharge.
And the site has a schematic for a system using this tank with a combi.
I have attached this diagram.

I would really like to have your views on this solution, as if it is
ok, it could provide me an answer and looks pretty easy to install,
although I am not sure what is different between this and a
"conventional" system!

A conventional system is using a system boiler and no mains pressure to the
shower. All is off the cold tank in the loft.

I prefer a combination cylidner of tank/cylidner with a quick recovery coil
to do all oulets at low pressure and a combi to do the high pressure shower
only. The heating side of the combi re-heats the cylidner. Justy like the
drawing on Albion.
Look at: http://www.rcmgroup.co.uk/specialized.htm The bottom one on the
right, sized to suit. Far better setup than than an unvented cylidner, or
silly power shower pumps.

Using a combination tank/cylinder eliminates tanks in the loft. In fact you
could put it in the loft out of the way.

It gives you what you want. Instant high pressure showers from the combi.
Fast flow for quick bath fillups.

"Andy Hall" wrote in message
...
On Sun, 23 Jan 2005 21:38:05 +0000, AndyHingston
wrote:


Hi All,

I am still deciding on the best replacement heating system and the DHW
flow rate is quite important. Whilst browsing many websites I came
across the Albion Water Heaters http://www.albion-online.co.uk site and
in particular the Superduty tanks that provide a very quick recharge.
And the site has a schematic for a system using this tank with a combi.
I have attached this diagram.

I would really like to have your views on this solution, as if it is
ok, it could provide me an answer and looks pretty easy to install,
although I am not sure what is different between this and a
"conventional" system!




It's basically a conventional storage system with the CH part of the
combi used to heat the radiators or the cylinder. Not an
unreasonable solution. Flow rate for the bath can be what you want it
to be if you have a large enough tank and cylinder and you do some of
the pipework from tank to cylinder to tap in 28mm.

However, watch out for the wording.

The 45 litre CF45 will contain water at 60 degrees, but the amount
stored could well be too little for filling a bath. The heat
exchanger is quite efficient because it has a large surface area, but
will be limited by what the boiler can produce.

The water could be stored at 80C and a blending valve on the hot water
draw-off takes water down to 45C or so. This in effect makes the cylinder
larger. Having a flow switch on the DHW to bring on the boiler immediately
hot water id drawn off, also will extend the size of the cylinder. In
effect using the two points above you can make the cylinder give as much
water as an 80 litre cylinder. If space is a problem then this is the way.
A 45 litre cylinder can go in a kitchen cupboard.

Also see: http://range-cylinders,co.uk

On Sun, 23 Jan 2005 23:42:42 -0000, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Sun, 23 Jan 2005 21:38:05 +0000, AndyHingston
wrote:


Hi All,

I am still deciding on the best replacement heating system and the DHW
flow rate is quite important. Whilst browsing many websites I came
across the Albion Water Heaters http://www.albion-online.co.uk site and
in particular the Superduty tanks that provide a very quick recharge.
And the site has a schematic for a system using this tank with a combi.
I have attached this diagram.

I would really like to have your views on this solution, as if it is
ok, it could provide me an answer and looks pretty easy to install,
although I am not sure what is different between this and a
"conventional" system!




It's basically a conventional storage system with the CH part of the
combi used to heat the radiators or the cylinder. Not an
unreasonable solution. Flow rate for the bath can be what you want it
to be if you have a large enough tank and cylinder and you do some of
the pipework from tank to cylinder to tap in 28mm.

However, watch out for the wording.

The 45 litre CF45 will contain water at 60 degrees, but the amount
stored could well be too little for filling a bath. The heat
exchanger is quite efficient because it has a large surface area, but
will be limited by what the boiler can produce.

The water could be stored at 80C and a blending valve on the hot water
draw-off takes water down to 45C or so. This in effect makes the cylinder
larger. Having a flow switch on the DHW to bring on the boiler immediately
hot water id drawn off, also will extend the size of the cylinder. In
effect using the two points above you can make the cylinder give as much
water as an 80 litre cylinder. If space is a problem then this is the way.
A 45 litre cylinder can go in a kitchen cupboard.

Also see: http://range-cylinders,co.uk




Storing the water at 80 degrees increases the effective capacity of a
45 litre cylinder to *up to* 60 litres.

A flow switch may improve that a little, but may not be desirable,
since without additional controls, the boiler would cycle each time a
tap is turned on and off. Then the system becomes more complex and
further cost is added.

Unless space is exceptionally tight, a larger cylinder is a more
sensible option for a system like this.



--

..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Sun, 23 Jan 2005 23:42:42 -0000, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Sun, 23 Jan 2005 21:38:05 +0000, AndyHingston
wrote:


Hi All,

I am still deciding on the best replacement heating system and the DHW
flow rate is quite important. Whilst browsing many websites I came
across the Albion Water Heaters http://www.albion-online.co.uk site
and
in particular the Superduty tanks that provide a very quick recharge.
And the site has a schematic for a system using this tank with a
combi.
I have attached this diagram.

I would really like to have your views on this solution, as if it is
ok, it could provide me an answer and looks pretty easy to install,
although I am not sure what is different between this and a
"conventional" system!




It's basically a conventional storage system with the CH part of the
combi used to heat the radiators or the cylinder. Not an
unreasonable solution. Flow rate for the bath can be what you want it
to be if you have a large enough tank and cylinder and you do some of
the pipework from tank to cylinder to tap in 28mm.

However, watch out for the wording.

The 45 litre CF45 will contain water at 60 degrees, but the amount
stored could well be too little for filling a bath. The heat
exchanger is quite efficient because it has a large surface area, but
will be limited by what the boiler can produce.

The water could be stored at 80C and a blending valve on the hot water
draw-off takes water down to 45C or so. This in effect makes the cylinder
larger. Having a flow switch on the DHW to bring on the boiler
immediately
hot water id drawn off, also will extend the size of the cylinder. In
effect using the two points above you can make the cylinder give as much
water as an 80 litre cylinder. If space is a problem then this is the
way.
A 45 litre cylinder can go in a kitchen cupboard.

Also see: http://range-cylinders,co.uk

Storing the water at 80 degrees increases
the effective capacity of a
45 litre cylinder to *up to* 60 litres.

yep!

A flow switch may improve that a little,

Yes up to 80 litres, if the boiler is approx 25-28 kW

but may not be desirable,
since without additional controls, the
boiler would cycle each time a
tap is turned on and off.

So, the boiler cycles on and off, so does a combi. An immersion probe stat
can be fitted right near the bottom of the cylinder to detect cold water is
entering and switches on the boiler on pronto. This prevents boiler cycling
when taps are turned on.

Then the system becomes more complex and
further cost is added.

Nope. see above.

Unless space is exceptionally tight,
a larger cylinder is a more
sensible option for a system like this.

Space must be tight as he is wanting a small cylinder. It may be best to
get a square tank specifically made to size by Elson. That will store more
water. A 12" high x 20" d x 23" w, square will go easily into a kitchen
cupboard bottom and holds 90 litres. Put a blending valve on and store
water at 80C and it will produce about 120 litres of hot water.

On Mon, 24 Jan 2005 00:25:53 -0000, "IMM" wrote:


"Andy Hall" wrote in message


Storing the water at 80 degrees increases
the effective capacity of a
45 litre cylinder to *up to* 60 litres.

yep!

A flow switch may improve that a little,

Yes up to 80 litres, if the boiler is approx 25-28 kW


It's impossible to say that because you don't know the flow rate
through the cylinder. Without that information, you have no data to
calculate the amount of energy that 25kW would deliver into the
cylinder.


but may not be desirable,
since without additional controls, the
boiler would cycle each time a
tap is turned on and off.

So, the boiler cycles on and off, so does a combi. An immersion probe stat
can be fitted right near the bottom of the cylinder to detect cold water is
entering and switches on the boiler on pronto. This prevents boiler cycling
when taps are turned on.

OK, so the flow switch was a bad idea.......



Then the system becomes more complex and
further cost is added.

Nope. see above.

By reverting back to a thermostat.


Unless space is exceptionally tight,
a larger cylinder is a more
sensible option for a system like this.

Space must be tight as he is wanting a small cylinder. It may be best to
get a square tank specifically made to size by Elson. That will store more
water. A 12" high x 20" d x 23" w, square will go easily into a kitchen
cupboard bottom and holds 90 litres. Put a blending valve on and store
water at 80C and it will produce about 120 litres of hot water.

Further misinformation.

A tank of the dimensions you give will only hold 90 litres if *all* of
that space is used for water storage. Either this would imply no
insulation, or the net storage capacity would be less.

If the tank has 50mm of insulation, the net dimensions would be
20.5cm x 40.8cm x 48.5cm and would have a capacity of 40.5 litres

With 30mm of insulation, net dimensions would be 24.5 x 45 x 52.5cm
giving just under 58 litres.

Neither anywhere near 90 litres.



--

..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Mon, 24 Jan 2005 00:25:53 -0000, "IMM" wrote:


"Andy Hall" wrote in message


Storing the water at 80 degrees increases
the effective capacity of a
45 litre cylinder to *up to* 60 litres.

yep!

A flow switch may improve that a little,

Yes up to 80 litres, if the boiler is approx 25-28 kW


It's impossible to say that because you don't know the flow rate
through the cylinder. Without that information, you have no data to
calculate the amount of energy that 25kW would deliver into the
cylinder.


but may not be desirable,
since without additional controls, the
boiler would cycle each time a
tap is turned on and off.

So, the boiler cycles on and off, so does a combi. An immersion probe
stat
can be fitted right near the bottom of the cylinder to detect cold water
is
entering and switches on the boiler on pronto. This prevents boiler
cycling
when taps are turned on.

OK, so the flow switch was a bad idea.......

No. two ways of achieving the same.

Then the system becomes more complex and
further cost is added.

Nope. see above.

By reverting back to a thermostat.


Unless space is exceptionally tight,
a larger cylinder is a more
sensible option for a system like this.

Space must be tight as he is wanting a small cylinder. It may be best to
get a square tank specifically made to size by Elson. That will store
more
water. A 12" high x 20" d x 23" w, square will go easily into a kitchen
cupboard bottom and holds 90 litres. Put a blending valve on and store
water at 80C and it will produce about 120 litres of hot water.

Further misinformation.

snip real drivel

The message
from "IMM" contains these words:

snip real drivel

As usual dIMM hasn't a clue about the use of figures and switches to
denial mode. I think he must have been an ostrich in his previous
existence.

--
Roger

"Roger" wrote in message
k...
The message
from "IMM" contains these words:

snip real drivel

As usual

snip more real drivel