"Tim S" wrote in message
...
Hi all,

This has been done to death in the past... But I'm looking to see if
there's
any new developments I've missed.

I want a thermal store/heatbank, about 200-220 litres in capacity, for a
fully open vented system, to buy next March.

So far:

DPS - about 1750 quid
McDonald Thermflow - 890
Gledhill boilermate - 1300

(Prices inc VAT, not exactly comparable, eg McDonald would need some extra
immersions, all except Gledhill need me to build relay control panel)
----------

DPS is nice and the company is easy to visit (Epsom) and I like being able
to specify everything and the use of largely standard ancillary components
(fixable easily, even if the company goes splat).
But, well, it's rather expensive for a tank with 3 pumps, 3x3kW of
immersions and a couple of mixers.

Gledhill is a nice appliance but full of specialist bits (cf DPS). I don't
think this one uses a plate exchanger either for HW.

McDonald - harder to specify and they're in Scotland. But more the sort of
money I'd expect to pay for a fancy tank.

These make stainless stores and heat banks. They will make custom, to
order - about 3 weeks delivery A heat bank, they will provide all the
components and you assemble. They are in the Midlands. Good stuff.
http://www.advanceappliances.co.uk/g...e_systems.html

Look at:
http://www.rcmgroup.co.uk/specialize...ower/index.htm
http://www.mcdonald-engineers.com
http://www.elsonho****er.co.uk/ (make square storage vessels and thermal
stores)
http://www.heatweb.com (make heat banks and storage vessels to size)
http://www.albion-online.co.uk (make thermal stores and storage vessels)
http://www.range-cylinders.co.uk (make cylindrical heat banks and storage
vessels)
http://www.gledhill.net (make heat banks and storage vessels)
http://www.newarkcyl.freeserve.co.uk (make cylindrical thermal stores and
storage vessels. They are quite cheap)
http://www.telford-group.com (make cylindrical thermal stores and storage
vessels. Tristore)

"Doctor Drivel" wrote in message
...

"Tim S" wrote in message
...
Hi all,

This has been done to death in the past... But I'm looking to see if
there's
any new developments I've missed.

I want a thermal store/heatbank, about 200-220 litres in capacity, for a
fully open vented system, to buy next March.

So far:

DPS - about 1750 quid
McDonald Thermflow - 890
Gledhill boilermate - 1300

(Prices inc VAT, not exactly comparable, eg McDonald would need some
extra
immersions, all except Gledhill need me to build relay control panel)
----------

DPS is nice and the company is easy to visit (Epsom) and I like being
able
to specify everything and the use of largely standard ancillary
components
(fixable easily, even if the company goes splat).
But, well, it's rather expensive for a tank with 3 pumps, 3x3kW of
immersions and a couple of mixers.

Gledhill is a nice appliance but full of specialist bits (cf DPS). I
don't
think this one uses a plate exchanger either for HW.

McDonald - harder to specify and they're in Scotland. But more the sort
of
money I'd expect to pay for a fancy tank.

These make stainless stores and heat banks. They will make custom, to
order - about 3 weeks delivery A heat bank, they will provide all the
components and you assemble. They are in the Midlands. Good stuff.
http://www.advanceappliances.co.uk/g...e_systems.html


They will also make a pressurised thermal store or heat bank. Then a system
boiler can be fitted directly - without coils. Also the heating circuit too.

Copperform do a copper pressurised thermal store - internal coil.
http://www.copperform.co.uk

"Tim S" wrote in message
...
Hi all,

This has been done to death in the past... But I'm looking to see if
there's
any new developments I've missed.

I want a thermal store/heatbank, about 200-220 litres in capacity, for a
fully open vented system, to buy next March.

So far:

DPS - about 1750 quid
McDonald Thermflow - 890
Gledhill boilermate - 1300

Gledhill also do the torrent:

On 18 Dec, 23:52, "Doctor Drivel" wrote:
"Tim S" wrote in message
.. .
Hi all,

This has been done to death in the past... But I'm looking to see if
there's
any new developments I've missed.

I want a thermal store/heatbank, about 200-220 litres in capacity, for a
fully open vented system, to buy next March.

So far:

DPS - about 1750 quid
McDonald Thermflow - 890
Gledhill boilermate - 1300

Gledhill also do the torrent:

gledhill is also gone bust. KEep a way or loose yourmoney

wrote in message
...
On 18 Dec, 23:52, "Doctor Drivel" wrote:
"Tim S" wrote in message
.. .
Hi all,

This has been done to death in the past... But I'm looking to see if
there's
any new developments I've missed.

I want a thermal store/heatbank, about 200-220 litres in capacity,
for a
fully open vented system, to buy next March.

So far:

DPS - about 1750 quid
McDonald Thermflow - 890
Gledhill boilermate - 1300

Gledhill also do the torrent:

gledhill is also gone bust. KEep a way or loose yourmoney

Gledhill has not gone bust. One division folded. They are trading as normal
and not under administration.

On 18 Dec, 23:13, "Doctor Drivel" wrote:
"Doctor Drivel" wrote in message

...





"Tim S" wrote in message
. ..
Hi all,

This has been done to death in the past... But I'm looking to see if
there's
any new developments I've missed.

I want a thermal store/heatbank, about 200-220 litres in capacity, for a
fully open vented system, to buy next March.

So far:

DPS - about 1750 quid
McDonald Thermflow - 890
Gledhill boilermate - 1300

(Prices inc VAT, not exactly comparable, eg McDonald would need some
extra
immersions, all except Gledhill need me to build relay control panel)
----------

DPS is nice and the company is easy to visit (Epsom) and I like being
able
to specify everything and the use of largely standard ancillary
components
(fixable easily, even if the company goes splat).
But, well, it's rather expensive for a tank with 3 pumps, 3x3kW of
immersions and a couple of mixers.

Gledhill is a nice appliance but full of specialist bits (cf DPS). I
don't
think this one uses a plate exchanger either for HW.

McDonald - harder to specify and they're in Scotland. But more the sort
of
money I'd expect to pay for a fancy tank.

These make stainless stores and heat banks. They will make custom, to
order - about 3 weeks delivery A heat bank, they will provide all the
components and you assemble. They are in the Midlands. Good stuff.
http://www.advanceappliances.co.uk/g...e_systems.html

They will also make a pressurised thermal store or heat bank. Then a system
boiler can be fitted directly - without coils. Also the heating circuit too.
keep a way frompressurised , dangeros , BIG BOOOOOOOOM
Copperform do a copper pressurised thermal store - internal coil.

http://www.copperform.co.uk

coughed up some electrons that declared:


gledhill is also gone bust. KEep a way or loose yourmoney

Well, to be exact, half has gone bust - specifically the half that did the
interesting products from my POV.

Cheers

Tim

Doctor Drivel coughed up some electrons that declared:

Gledhill also do the torrent:

I'd don't think the Torrent is suitable unfortunately - I'm looking for a
system that will power the rads too (load smoothing on the boiler).

After having done a lot more reading, I've made two observations (which
agree with the wiki entry on heatbanks):

1) Plate exchangers for HW probably produce greater power transfer = flow;
But, with an uncontrolled pump, they are liable to wreck the stratification
in the bank. Gledhill dealt with this by means of a temp sensors to
modulating pump control loop. No-one else does this AFAICS. Even the pump
(Grundfos UPR 15-50) is a bit of a weirdy - not even mentioned on
Grundfos's website, but can be bought as a Gledhill spare part easily
enough, meaning, that given time, I could adapt one onto a DPS bank and
make my own controller (AVR cpu won't be difficult, simple closed loop
control with a bit of damping should do it).

2) Internal coil exchangers for HW probably destroy the stratification less
and need no pump and are inherently self balancing, and may be a good
solution along as it can deliver the power transfer for a good HW flow
rate.

I'm not sure why more manufacturers don't use modulating pumps.

Cheers

tim

Doctor Drivel coughed up some electrons that declared:

They will also make a pressurised thermal store or heat bank. Then a
system boiler can be fitted directly - without coils. Also the heating
circuit too.

Copperform do a copper pressurised thermal store - internal coil.
http://www.copperform.co.uk

I'm shying away from pressurised systems. I'd rather chase airlocks and
bubbles than worry about blowing things up. Irrational, perhaps, but I
understand open vented systems and I like them.

Cheers

Tim

Doctor Drivel coughed up some electrons that declared:

Thanks for this

Quick reordering:

http://www.mcdonald-engineers.com
http://www.heatweb.com (make heat banks and storage vessels to size)
http://www.albion-online.co.uk (make thermal stores and storage vessels)
http://www.range-cylinders.co.uk (make cylindrical heat banks and storage
vessels)

I've studied most of those guys - McDonald are cheap but DPS have more
flexibility is my immediate conclusion.

http://www.gledhill.net (make heat banks and storage vessels)

Good stuff is dead

http://www.rcmgroup.co.uk/specialize...ower/index.htm

Link dead

http://www.elsonho****er.co.uk/ (make square storage vessels and thermal
stores)

http://www.newarkcyl.freeserve.co.uk (make cylindrical thermal stores and
storage vessels. They are quite cheap)

http://www.telford-group.com (make cylindrical thermal stores and storage
vessels. Tristore)

These all look fairly basic.

I think DPS is looking like the best bet. I could leave the way open to
modify the system later - apart from the core tank all the bits are pretty
standard.

There doesn't seem to be very much innovation in this field. Most of these
guys are metal bashers and one that tried to innovate dropper dead.

Cheers

Tim

"Tim S" wrote in message
...
Doctor Drivel coughed up some electrons that declared:

Thanks for this

Quick reordering:

http://www.mcdonald-engineers.com
http://www.heatweb.com (make heat banks and storage vessels to size)
http://www.albion-online.co.uk (make thermal stores and storage vessels)
http://www.range-cylinders.co.uk (make cylindrical heat banks and storage
vessels)

I've studied most of those guys - McDonald are cheap but DPS have more
flexibility is my immediate conclusion.

http://www.gledhill.net (make heat banks and storage vessels)

Good stuff is dead

http://www.rcmgroup.co.uk/specialize...ower/index.htm

Link dead

Now copperform.

http://www.elsonho****er.co.uk/ (make square storage vessels and thermal
stores)

http://www.newarkcyl.freeserve.co.uk (make cylindrical thermal stores and
storage vessels. They are quite cheap)

http://www.telford-group.com (make cylindrical thermal stores and storage
vessels. Tristore)

These all look fairly basic.

I think DPS is looking like the best bet. I could leave the way open to
modify the system later - apart from the core tank all the bits are pretty
standard.

There doesn't seem to be very much innovation in this field. Most of these
guys are metal bashers and one that tried to innovate dropper dead.

They are in the Midlands. Good stuff.
http://www.advanceappliances.co.uk/g...e_systems.html

Tell me what you want and I will narrow it down.

"Tim S" wrote in message
...
Doctor Drivel coughed up some electrons that declared:

Gledhill also do the torrent:

I'd don't think the Torrent is suitable unfortunately - I'm looking for a
system that will power the rads too (load smoothing on the boiler).

After having done a lot more reading, I've made two observations (which
agree with the wiki entry on heatbanks):

1) Plate exchangers for HW probably produce
greater power transfer = flow; But, with an
uncontrolled pump, they are liable to wreck the stratification
in the bank. Gledhill dealt with this by means of a temp sensors to
modulating pump control loop. No-one else does this AFAICS.

DPS use a Danfos RAKV valve to restrict the flow and maintain the DHW
temperature.
http://www.heatweb.com/pdf/DPS/ZedStoreDistrict.pdf

Best use a very large plate heat exchanger - 150 kW. These are very
efficient and will work at a very low store temperature. This means if
stratification is messed up somewhat or the temperature is just low they
deliver the DHW.

Stratification is not messed up too much as the volume of water in the
cylinder is quite large and the DHW pump pumps the right way. The boiler
pump pumps the wrong way but very hot water is pumped into the top of the
cylinder, so not a problem.

A spreader can be fitted on the DHW return. Drill out a compression fitting
pipe stop and slide in the pipe. Have an internal pipe stop end. Drill
holes in the pipe and have the holes face downwards. All pumps must pump
away from the store.

The bottom of the cylinder can be very cool - 30C, while the top 75C. High
condensing efficiency is guaranteed for most of the re-heat burn.

Have a Smart pump on the CH flow with a check valve after. Have a
Magnaclean filter on the CH loop return - essential. With a Smart pump you
can have TRVs all around.

Look at: AVANTA 18v System Only Option 6
http://www.avantaplus.com/docs/Issue...%20Booklet.pdf

This is a dual temperature boiler. The Broag 18V is open vented with an
internal weather compensator. It is very well priced and a quality Dutch
product. An external 3-way valve is energised by two anti-cycle stats on
the upper part (DHW) of the store. All the boilers heat at full temp, goes
to reheating the DHW. When satisfied the 3-way valve diveerts to heating
only the bottom section to the dictates of the weather compensator.

The room stat is linked out and the 3-way valve is controlled by the boiler.
The cyl stat is wired into the boiler. (the two stats using a relay). Just
buy an outside weather temp sensor.

Then the rad water is at the right temperature and in a large volume in the
store too preventing boiler cycling. No mixing valves are needed for CH as
all is done by the boiler controls.

Advance Appliances will put the probes and tappings in the place you
specify. They will provide the plate heat exchanger and most of the bits
and you just connect up. They don't like to connect up electrical parts as
they need to test have certificates etc.

I'm not sure why more manufacturers don't use modulating pumps.

Why when a Danfos valve can give the DHW temp and restrict pump flow?

Doctor Drivel coughed up some electrons that declared:


DPS use a Danfos RAKV valve to restrict the flow and maintain the DHW
temperature.
http://www.heatweb.com/pdf/DPS/ZedStoreDistrict.pdf

That is interesting - thanks

Cheers

Tim

"Tim S" wrote in message
...
Doctor Drivel coughed up some electrons that declared:


DPS use a Danfos RAKV valve to restrict the flow and maintain the DHW
temperature.
http://www.heatweb.com/pdf/DPS/ZedStoreDistrict.pdf

That is interesting - thanks

That is a two-port valve. You can use a 3-port diverter body and have one
port back to the store and the other back to the other side of the pump.
Then the pump will never pump on nothing. If the hot port is closed it
pumps back on itself. After the port back to the suction side of the pump
fit an adjustable restrictor valve to balance up.

"Tim S" wrote in message
...
Doctor Drivel coughed up some electrons that declared:


DPS use a Danfos RAKV valve to restrict the flow and maintain the DHW
temperature.
http://www.heatweb.com/pdf/DPS/ZedStoreDistrict.pdf

That is interesting - thanks

That is a RAVK.

Doctor Drivel coughed up some electrons that declared:

RAVK

Brilliant, thanks.

I'm going to see DPS at their factory in the new year. Looking like I should
use one of their standard GX heatbanks and stick a RAVK valve in
appropriate places along with a self modulating Alpha pump (which are more
common than the external control modulating).

Cheers

Tim

"Tim S" wrote in message
...
Doctor Drivel coughed up some electrons that declared:

RAVK

Brilliant, thanks.

I'm going to see DPS at their factory in the new year. Looking like I
should
use one of their standard GX heatbanks and stick a RAVK valve in
appropriate places along with a self modulating Alpha pump (which are more
common than the external control modulating).

What do you mean by: "(which are more common than the external control
modulating)."? Are you on about the DHW side?

An Alpha pump can be on the CH loop with TRVs all around and no wall stat.
Simple and easy.

Doctor Drivel coughed up some electrons that declared:


"Tim S" wrote in message
...
Doctor Drivel coughed up some electrons that declared:

RAVK

Brilliant, thanks.

I'm going to see DPS at their factory in the new year. Looking like I
should
use one of their standard GX heatbanks and stick a RAVK valve in
appropriate places along with a self modulating Alpha pump (which are
more common than the external control modulating).

What do you mean by: "(which are more common than the external control
modulating)."? Are you on about the DHW side?

Yes. The Gledhill Boilermate OV (and OV SOL) used a Grundfos UPR 3 wire
pump, which is externally speed controllable (don't know if it's was an
analogue voltage or PWM control - can't find any datasheets)

There was a temp sensor on the HW outlet pipe of the plate exchanger and a
computer in between that formed a control loop. DHW not warm enough = make
pump on primary side go faster.

The hydraulics of the control loop (the water) are essentially the same as
the ZED system, only ZED uses a mechanical means to restrict primary flow
to the plate with its temp sensor on the DHW output. I'm suggesting that if
you restrict the flow mechanically, it would be a good idea to use a self
modulating pump (which are more common than the 3 wire kind) so the pump
isn't beating its brains out when a small flow is called for.

Either seem better than a mixer that ends up with full flow round the
primary whether it's needed or not.

An Alpha pump can be on the CH loop with TRVs all around and no wall stat.
Simple and easy.

Yeah I was going to do that.

At least, if DPS don't want to build me a bank with the aforementioned bits,
they will allow me to buy a bank with bits missing so I can DIY the
appropriate valves and pumps myself. I like DPS in that respect - and
there's none of this "we don't like talking to the end user" ********,
which I did get from Gledhill until I was on the point of yelling at them.
I think Gledhill's attitude didn't do them any favours and I've other
similar complaints on various forums.

Cheers

Tim

"Tim S" wrote in message
...
Doctor Drivel coughed up some electrons that declared:


"Tim S" wrote in message
...
Doctor Drivel coughed up some electrons that declared:

RAVK

Brilliant, thanks.

I'm going to see DPS at their factory in the new year. Looking like I
should
use one of their standard GX heatbanks and stick a RAVK valve in
appropriate places along with a self modulating Alpha pump (which are
more common than the external control modulating).

What do you mean by: "(which are more common than the external control
modulating)."? Are you on about the DHW side?

Yes. The Gledhill Boilermate OV (and OV SOL) used a Grundfos UPR 3 wire
pump, which is externally speed controllable (don't know if it's was an
analogue voltage or PWM control - can't find any datasheets)

There was a temp sensor on the HW outlet pipe of the plate exchanger and a
computer in between that formed a control loop. DHW not warm enough =
make
pump on primary side go faster.

The hydraulics of the control loop (the water) are essentially the same as
the ZED system, only ZED uses a mechanical means to restrict primary flow
to the plate with its temp sensor on the DHW output. I'm suggesting that
if
you restrict the flow mechanically, it would be a good idea to use a self
modulating pump (which are more common than the 3 wire kind) so the pump
isn't beating its brains out when a small flow is called for.

As I said, a 3-port diverter RAVK can do the job with a simple cheap pump -
the other port just lops back to the suction side of the pump with an
adjusting valve. Or have a 2-port and a pressure balancing valve after the
pump which again loop back on the other side of the pump - may be cheaper.

Having a Smart pump and a RAVK may mean that one control will fight the
other. I have not rigged that sort up yet and tested for stability. It may
be the answer, but on the surface poses potential problems.

At least, if DPS don't want to build me a bank with the aforementioned
bits,
they will allow me to buy a bank with bits missing so I can DIY the
appropriate valves and pumps myself. I like DPS in that respect - and
there's none of this "we don't like talking to the end user" ********,
which I did get from Gledhill until I was on the point of yelling at them.
I think Gledhill's attitude didn't do them any favours and I've other
similar complaints on various forums.

Gledhill at one time would not supply individual units, only a minimum of
around 5 of them. They only dealt with the new-build sector - the one which
went under. As time went on they relaxed their view.

They had the right idea, having it all easily installed in one case. It
looks neat and the insulation value is phenomenal. DPS and others should
take note.

They never kept up, right with the times - a difficult thing I know. New
boilers like the Broag, and others, with more advanced control systems, like
integral weather compensation, etc, would make some stores sing. Although
Gledhill would put in a Smart pump for you on the CH loop, which saved
installation costs of a room stat. They never took advantage of new
controls on system/heating boilers. I described the Avantplus 18V connected
to a store and real cheap for what the whole system offers.

Gledhill found it difficult offering small improvements, at a little extra
cost, as builders could not see the advantages. Weather compensation? Most
haven't a clue what it is or what it offers. I have seen some boiler with
integral weather compensation and no outside senor fitted. They fit just
on-off room stats. A total waste of a control system because of ignorant
drains centric plumbers. Weather compensation is a good selling point for
homes - the weather lowers and raises the rad temps. And saves money -
selling point too.

Gledhill also never offered stainless stores. I would only go stainless
these days as they are now cost effective. And they last and last.
Advanced Appliances a make custom to order.

Gledhill also do not offer pressurised stores. No G3 required and only a
pressure relief valve needed on the store - also one on the boiler. Only
charged to 1 bar. Best have a temperature high limit with them in case.

If Gledhill, or others, offered:

a) a cased pressurised heat bank
b) integral expssionn vessel
c) integral boiler,
d) weather compensation
e) TRVs all around option
f) integral Magnaclean type of filter
g) Easy to fit
h) Direct boiler and rad circuits

Then it would be No. 1. on SEBUK in efficiency, as the condensing boiler
would rarely would not be condensing with very low temperatures. The boiler
would not cycle and always on full flow through the boiler, which means it
would last and last as controls are not being over activated. The same with
the pumps - no restrictions on flow meaning an easy long life.

ACV Heatmaster, go some way to offering that, but G3 is required and some
external pumps, etc. The Heatmaster is around £3K, but still worth it for
a 2 bathroom one-box solution, as all is in one case.

Doctor Drivel coughed up some electrons that declared:

As I said, a 3-port diverter RAVK can do the job with a simple cheap pump
- the other port just lops back to the suction side of the pump with an
adjusting valve. Or have a 2-port and a pressure balancing valve after
the pump which again loop back on the other side of the pump - may be
cheaper.

Ah, I get it.

Yes - that looks like a solution too.

Cheers

Tim

Tim S wrote:

I'm going to see DPS at their factory in the new year.

It's a fun place to try to find. Behind a row of shops.

Looking like I should use one of their standard GX heatbanks and stick a
RAVK valve in appropriate places along with a self modulating Alpha pump
(which are more common than the external control modulating).

We've got a GX heatbank which is intended to accumulate hot water from
solar, log burner and an LPG boiler. However due to a bone-idle builder
I can't yet give a performance report.

"YAPH" wrote in message
...
On Fri, 19 Dec 2008 12:38:28 +0000, Tim S wrote:

Doctor Drivel coughed up some electrons that declared:

As I said, a 3-port diverter RAVK can do the job with a simple cheap
pump
- the other port just lops back to the suction side of the pump with an
adjusting valve. Or have a 2-port and a pressure balancing valve after
the pump which again loop back on the other side of the pump - may be
cheaper.

Ah, I get it.

Yes - that looks like a solution too.

Tim, I know it's a while off yet but when you do get your system up and
running (and have had time to see how well it works) perhaps you'd report
back here to us on it (maybe with some photos)? It would be a good
addition to the wiki article which IIRC merely speculated on this sort of
approach.

This man DIYed a solar heat bank to great success:
http://www.diynot.com/forums/viewtopic.php?t=137289

He was guided through. His comments on its performance is worth noting.

Doctor Drivel coughed up some electrons that declared:

This man DIYed a solar heat bank to great success:
http://www.diynot.com/forums/viewtopic.php?t=137289

He was guided through. His comments on its performance is worth noting.

Most interesting - thanks - I'm printing it out to read again later.

May Santa bring you 27 mince pies and new batteries for your Prius.

Happy Xmas!

Cheers

Tim

PS

I had started to wonder about regulating the return temp[1] on the primary
side of the plate exchanger for the DHW. It's not like we need totally
precise DHW temp regulation, plate exchangers apparantly get the output
water up to the virtually the temperature of the primary side and anything
that reduced the primary flow back to the store when it's not needed will
benefit stratification.

[1] Might be easier to arrange

Cheers

Tim

YAPH wrote:
On Fri, 19 Dec 2008 12:38:28 +0000, Tim S wrote:

Doctor Drivel coughed up some electrons that declared:

As I said, a 3-port diverter RAVK can do the job with a simple cheap pump
- the other port just lops back to the suction side of the pump with an
adjusting valve. Or have a 2-port and a pressure balancing valve after
the pump which again loop back on the other side of the pump - may be
cheaper.
Ah, I get it.

Yes - that looks like a solution too.

Tim, I know it's a while off yet but when you do get your system up and
running (and have had time to see how well it works) perhaps you'd report
back here to us on it (maybe with some photos)? It would be a good
addition to the wiki article which IIRC merely speculated on this sort of
approach.




Sure thing - behappy too

Cheers

Tim

"Tim S" wrote in message
...
Doctor Drivel coughed up some electrons that declared:

This man DIYed a solar heat bank to great success:
http://www.diynot.com/forums/viewtopic.php?t=137289

He was guided through. His comments on its performance is worth noting.

Most interesting - thanks - I'm printing
it out to read again later.

There are photos there too.
He had to fit an accumulator which is not applicable to you.
There are far too many elbows for my liking in the installation, but does
show a finished system.
He fitted a needless by-pass on an Alpha pump, which needs to be taken out,
which he realised after taking temperatures.
He never fitted a simple pipe spreader either which would enhance
stratification, but the condensing performance is still startling.
As the figures indicate a large kW plate heat exchanger pays dividends, and
not that much more expensive either.

May Santa bring you 27 mince pies and new batteries for your Prius.

The batteries are in great nick and fab. I don't like minced pies.

I had started to wonder about regulating the return temp[1] on the primary
side of the plate exchanger for the DHW. It's not like we need totally
precise DHW temp regulation, plate exchangers apparantly get the output
water up to the virtually the temperature of the primary side and anything
that reduced the primary flow back to the store when it's not needed will
benefit stratification.

The RAVK sensing on one side on the plate and operating on the other is the
best way.

Doctor Drivel coughed up some electrons that declared:


"Tim S" wrote in message
...
Doctor Drivel coughed up some electrons that declared:

This man DIYed a solar heat bank to great success:
http://www.diynot.com/forums/viewtopic.php?t=137289

He was guided through. His comments on its performance is worth noting.

Most interesting - thanks - I'm printing
it out to read again later.

There are photos there too.
He had to fit an accumulator which is not applicable to you.
There are far too many elbows for my liking in the installation, but does
show a finished system.
He fitted a needless by-pass on an Alpha pump, which needs to be taken
out, which he realised after taking temperatures.
He never fitted a simple pipe spreader either which would enhance
stratification, but the condensing performance is still startling.
As the figures indicate a large kW plate heat exchanger pays dividends,
and not that much more expensive either.

Having printed it out, and read it at friends' this morning over coffee
(by "morning" I mean 11am) I was very impressed.

It's cemented the bits I was fairly certain about, added some interesting
stuff and clarified that I shouldn't be buying a very expensive lump of
copper from DPS (as fine folks as they are) - I should be buying a long
thin copper cylinder from a cheaper copper bashers and having them put in a
load more 22mm and immersion bosses where I want.

Let's face it - it's hardly going to take much more time to put together
with standard pumps, flowswitches and mixers, I can put a few extra
tappings in where I'm not sure of the optimum height and replumb later if
it turns out I made a mistake.

What I'd like to do is set up a simple electro-mechanical control system
that works (ie what DPS do), then later pepper it with sensors and a small
AVR cpu board of my design to measure everything. It should then become
clear if further optimisation and/or computer control is likely to be
beneficial - and if it is, I'll retain the electro-mechanical controls as a
failsafe (well, bloody computers always go wrong, don't they...)

May Santa bring you 27 mince pies and new batteries for your Prius.

The batteries are in great nick and fab. I don't like minced pies.

How about mincing pies then?

I had started to wonder about regulating the return temp[1] on the
primary side of the plate exchanger for the DHW. It's not like we need
totally precise DHW temp regulation, plate exchangers apparantly get the
output water up to the virtually the temperature of the primary side and
anything that reduced the primary flow back to the store when it's not
needed will benefit stratification.

The RAVK sensing on one side on the plate and operating on the other is
the best way.

But what's the time constant of the feedback loop likely to be - I feel it
may be too slow?...

Cheers

Tim

"Tim S" wrote in message
...

It's cemented the bits I was fairly
certain about, added some interesting
stuff and clarified that I shouldn't be buying
a very expensive lump of copper from DPS
(as fine folks as they are) - I should be buying a long
thin copper cylinder from a cheaper copper
bashers and having them put in a
load more 22mm and immersion bosses where I want.

That is what I told you.

Let's face it - it's hardly going to take much
more time to put together with standard pumps,
flowswitches and mixers, I can put a few extra
tappings in where I'm not sure of the optimum
height and replumb later if it turns out I made a mistake.

Yep. I guy I know, I taught him about assembling heat banks, assembles them
in his garage. Takes a hour or so. He used them in place of unvented
cylinder. He orders a combination cylinder from a local copper basher with
the tappings where he wants. He makes a fair amount and still undercuts an
unvented cylinder installation.

He does not try to sell the CH part as he finds the customers do not
understand the CH buffer benefits, so sells it as mains pressure DHW, just
replacing a DHW cylinder. When a comprehensive installation he does an
integrated CH/DHW heat bank using a Smart pump and no room stat and TRVs all
around.

What I'd like to do is set up a simple electro-mechanical control system
that works (ie what DPS do), then later pepper it with sensors and a small
AVR cpu board of my design to measure everything. It should then become
clear if further optimisation and/or computer control is likely to be
beneficial - and if it is, I'll retain the electro-mechanical controls as
a
failsafe (well, bloody computers always go wrong, don't they...)

Gledhill use a microprocessor to modulate the DHW pump and monitor the
store. Their pcbs are available, and if they do what you want use one of
those.

The RAVK sensing on one side on the plate
and operating on the other is
the best way.

But what's the time constant of the feedback loop
likely to be - I feel it may be too slow?...

They are fast enough and not too fast. They are used in District heating
sub stations. Oventrop also make them - maybe cheaper.
http://www.oventrop.co.uk/en/index.htm

Go to products, 3-way valves.

On 26 Dec, 21:15, "Doctor Drivel" wrote:
"Tim S" wrote in message

...

It's cemented the bits I was fairly
certain about, added some interesting
stuff and clarified that I shouldn't be buying
a very expensive lump of copper from DPS
(as fine folks as they are) - I should be buying a long
thin copper cylinder from a cheaper copper
bashers and having them put in a
load more 22mm and immersion bosses where I want.

That is what I told you.

Let's face it - it's hardly going to take much
more time to put together with standard pumps,
flowswitches and mixers, I can put a few extra
tappings in where I'm not sure of the optimum
height and replumb later if it turns out I made a mistake.

Yep. I guy I know, I taught him about assembling heat banks, assembles them
in his garage. Takes a hour or so. He used them in place of unvented
cylinder. He orders a combination cylinder from a local copper basher with
the tappings where he wants. He makes a fair amount and still undercuts an
unvented cylinder installation.

He does not try to sell the CH part as he finds the customers do not
understand the CH buffer benefits, so sells it as mains pressure DHW, just
replacing a DHW cylinder. When a comprehensive installation he does an
integrated CH/DHW heat bank using a Smart pump and no room stat and TRVs all
around.

What I'd like to do is set up a simple electro-mechanical control system
that works (ie what DPS do), then later pepper it with sensors and a small
AVR cpu board of my design to measure everything. It should then become
clear if further optimisation and/or computer control is likely to be
beneficial - and if it is, I'll retain the electro-mechanical controls as
a
failsafe (well, bloody computers always go wrong, don't they...)

Gledhill use a microprocessor to modulate the DHW pump and monitor the
store. Their pcbs are available, and if they do what you want use one of
those.
Watch youdont put money up front gleddhill is gone down thetubes,they
are like mfi& wollies they are bust

The RAVK sensing on one side on the plate
and operating on the other is
the best way.

But what's the time constant of the feedback loop
likely to be - I feel it may be too slow?...

They are fast enough and not too fast. They are used in District heating
sub stations. Oventrop also make them - maybe cheaper.http://www.oventrop.co.uk/en/index.htm

Go to products, 3-way valves.

wrote in message
...

Yes?