On Mon, 15 Nov 2004 16:40:21 +0000, John Aston wrote:

Thanks for your help to date. I've distilled the advice from various threads
in this newsgroup to come up with a possible heating design for my house.

The drawing HD01 at http://tinyurl.com/3zv2g shows the proposed hydraulic
design for a large domestic heating system. The boiler and hot water
cylinder is on the left hand side of the drawing, space heating is on the
right. (You might need to rotate the view so that the drawing is in
landscape orientation in your browser)

Some explanatory notes on the design are appended below. Any comments would
be gratefully received but my principal questions a

(1) The internal space heating requirement when it's -3°C outside is 31kW.
In addition, there is a 250L cylinder serving three showers and one bath for
a family of five. Is a 38kW boiler sufficient?

This is similar to a system I installed a couple of years ago. with a 170L
HWC and a Keston C40 (that's about 37kW output but runs at about 35kW due
to service main inadequacy). It works fine. Except I used a 5-way S-plan
and no UFH.

Since this is a sealed primary what does the 'top up' unit mean?


(2) I'm specifying 28mm pipe through the water softener and up to the
cylinder, 22mm for the boiler flow and return, 22mm to potable water cold
taps and 15mm everywhere else. Is that reasonable or over the top?

It's going to be quite some softener unit to process the flow that requires 28mm
pipe 8-)
Main Boiler flow and return should likely be 28mm even if only to the
diverter valve and last return T. Most boilers of this size wil likely have 28mm/R1
connections.
Cold: 22mm for the garden tap. Other wise it really is OTT.


(3) A 22mm pipe is teed off the secondary side of the low loss header. From
this 22mm pipe, I propose to tee off 15mm pipe to each heating zone. What is
the maximum distance between these 15mm tees, and what's the maximum
permissible distance from the furthest 15mm tee to the header? (Keston told
me that there is NO restriction)

Provided they leave and return in the same order. You have check valves to
prevent back flow in the inactive zones. It might mean you need a higher
pump setting for the farther zones.



(4) What's the best way of incorporating two towel rails (bottom right) into
the circuit so that the towel rails come on all year round when there is
either a call for heat or a call for hot water?

Right off the boiler flow and return, suitably balanced against hogging
all the flow.


Design:

The mains cold water supply is treated by a water softener (bottom left).
The softened water is fed to a 250L cylinder under pressure from an
accumulator which keeps the cold water at about 2.5 bar and provides a high
flow rate to all taps.

I take it that you have an inadequate water main?



The water in the cylinder is heated indirectly by the primary of a 38kW
fully-modulating condensing boiler in the room below the cylinder. Hot water
is circulated to the taps by means of a secondary pump. Because the system
is unvented, the hot water is also at a pressure of about 2.5 bar.

Bronze pump needed will (cost will equal total of all the other pumps). 8-(


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

On Mon, 06 Dec 2004 14:04:56 +0000, John Aston wrote:

IMM wrote in message
...

"John Aston" wrote in message
oups.com...
Thanks to everyone who contributed heating design ideas.

The design is finalised and I am considering placement of the
components.

I plan to put the 40kW condensing boiler (Keston C40) and cylinder in a
cupboard at one end of the bathroom. At the opposite end of the
bathroom, 4m away, is the adjoining wall with my bedroom.

Is the boiler likely to keep me awake at night if I put it in this
location?

Make sure the cupboard is well sealed and flimsey. You make need draught
stip on the doors to prevent sopunds getting oit. It does work.

Two Keston Celisus boilers are near the price of one 40kW Keston.


I've heard that the Keston boiler is noisier because the flue fan needs to
go faster to get the air through a 2 inch flue. Any Keston owners out there
care to comment?

As a Keston C25 owner and fitter of Keston systems I would say the
C25 is nigh on inaudible. The C40 is less quiet and in retrospect I would
fit 2x c25 in preference to one C40 - space permitting.
However most of the time the C40 would be nowhere near full power,
unlikely to operate at night, the noise seems mostly to come from
harshness of the bigger burner fan.

I'm not sure how you would implement the controls to decide when to use
the second boiler.

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

"Ed Sirett" wrote in message
news
On Mon, 06 Dec 2004 14:04:56 +0000, John Aston wrote:

IMM wrote in message
...

"John Aston" wrote in message
oups.com...
Thanks to everyone who contributed heating design ideas.

The design is finalised and I am considering placement of the
components.

I plan to put the 40kW condensing boiler (Keston C40) and cylinder in
a
cupboard at one end of the bathroom. At the opposite end of the
bathroom, 4m away, is the adjoining wall with my bedroom.

Is the boiler likely to keep me awake at night if I put it in this
location?

Make sure the cupboard is well sealed and flimsey. You make need
draught
stip on the doors to prevent sopunds getting oit. It does work.

Two Keston Celisus boilers are near the price of one 40kW Keston.


I've heard that the Keston boiler is noisier because the flue fan needs
to
go faster to get the air through a 2 inch flue. Any Keston owners out
there
care to comment?

As a Keston C25 owner and fitter of Keston systems I would say the
C25 is nigh on inaudible.

Those I have come across I would not describe as inaudible. Unless they
were duffers. They were early units and Keston have done a lot to the
Celsius since introduction.

"...sopunds getting oit."

Sounds like a line from 'The Jabberwocky'. The lad has a great future
in nonsense verse. His nonsense prose won't catch on, though.


Whether it would keep you awake? It depends on how noisy it is (I've no
idea) and how lightly you sleep (no idea). There is very little
background noise at, say, 4 a.m. when the boiler might fire up.
'Inaudible' sounds are much more intrusive.

I know a gas fitter who put a boiler in his loft, but found it woke
him up every morning. That was a few years back, boilers may be quieter
now.

In message , IMM
writes

Make sure the cupboard is well sealed and flimsey. You make need draught
stip on the doors to prevent sopunds getting oit. It does work.

Two Keston Celisus boilers are near the price of one 40kW Keston.


You've been quiet for the last few days. Been ill or ?

I'm as right as rain. I have been abroad jet setting.

Costa del Sol in the cheap season then ?

--
geoff

On Tue, 07 Dec 2004 22:14:34 GMT, raden wrote:

In message , IMM
writes

Make sure the cupboard is well sealed and flimsey. You make need draught
stip on the doors to prevent sopunds getting oit. It does work.

Two Keston Celisus boilers are near the price of one 40kW Keston.


You've been quiet for the last few days. Been ill or ?

I'm as right as rain. I have been abroad jet setting.

Costa del Sol in the cheap season then ?


Eyebyeza......?



--

..andy

To email, substitute .nospam with .gl

Ed Sirett wrote in message
news
On Mon, 15 Nov 2004 16:40:21 +0000, John Aston wrote:

The drawing HD01 at http://tinyurl.com/3zv2g shows the proposed
hydraulic
design for a large domestic heating system.
snip

This is similar to a system I installed a couple of years ago. with a 170L
HWC and a Keston C40 (that's about 37kW output but runs at about 35kW due
to service main inadequacy). It works fine. Except I used a 5-way S-plan
and no UFH.


Ed, how do you rate the C40? I'm intending to buy this boiler and Keston's
Spa 300L cylinder.

Since this is a sealed primary what does the 'top up' unit mean?


I was going to use it to add inhibitor to the heating system.

snip

Design:

The mains cold water supply is treated by a water softener (bottom
left).
The softened water is fed to a 250L cylinder under pressure from an
accumulator which keeps the cold water at about 2.5 bar and provides a
high
flow rate to all taps.

I take it that you have an inadequate water main?

It's borderline. Gemonix sell a 300 litre expansion vessel part ZI-318300
for £266.64+VAT.
http://www.geminox-uk.com/expansion_vessels.html
I hope that that will be OK for my application.


The water in the cylinder is heated indirectly by the primary of a 38kW
fully-modulating condensing boiler in the room below the cylinder. Hot
water
is circulated to the taps by means of a secondary pump. Because the
system
is unvented, the hot water is also at a pressure of about 2.5 bar.

Bronze pump needed will (cost will equal total of all the other pumps).
8-(


Thanks, Ed. Maybe I'll lay the pipe for the secondary loop and only add the pump later if the dead legs are a big problem.

John Aston wrote in message
.. .
Ed Sirett wrote in message
news
On Mon, 15 Nov 2004 16:40:21 +0000, John Aston wrote:

The drawing HD01 at http://tinyurl.com/3zv2g shows the proposed
hydraulic design for a large domestic heating system.
snip

This is similar to a system I installed a couple of years ago. with a
170L
HWC and a Keston C40 (that's about 37kW output but runs at about 35kW
due
to service main inadequacy). It works fine. Except I used a 5-way S-plan
and no UFH.


Since posting the drawing, I've decided to do away with the pumps on each
individual radiator circuit and replaced them with zone valves. A single
variable speed pump on the header's secondary outflow gets the hot water to
the various circuits.

I've also changed from Y-plan to S-plan.

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

Make sure the cupboard is well sealed and flimsey. You make need
draught
stip on the doors to prevent sopunds getting oit. It does work.

Two Keston Celisus boilers are near the price of one 40kW Keston.

You've been quiet for the last few days. Been ill or ?

I'm as right as rain. I have been abroad jet setting.

Costa del Sol in the cheap season then ?

I wish it was Maxie. All that cheap sagria!

"John Aston" wrote in message
.. .
Ed Sirett wrote in message
news
On Mon, 15 Nov 2004 16:40:21 +0000, John Aston wrote:

The drawing HD01 at http://tinyurl.com/3zv2g shows the proposed
hydraulic
design for a large domestic heating system.
snip

This is similar to a system I installed a couple of years ago. with a
170L
HWC and a Keston C40 (that's about 37kW output but runs at about 35kW
due
to service main inadequacy). It works fine. Except I used a 5-way S-plan
and no UFH.


Ed, how do you rate the C40? I'm intending to buy this boiler and Keston's
Spa 300L cylinder.

Since this is a sealed primary what does the 'top up' unit mean?


I was going to use it to add inhibitor to the heating system.

snip

Design:

The mains cold water supply is treated by a water softener (bottom
left).
The softened water is fed to a 250L cylinder under pressure from an
accumulator which keeps the cold water at about 2.5 bar and provides a
high
flow rate to all taps.

I take it that you have an inadequate water main?

It's borderline. Gemonix sell a 300 litre expansion vessel part ZI-318300
for £266.64+VAT.
http://www.geminox-uk.com/expansion_vessels.html
I hope that that will be OK for my application.


The water in the cylinder is heated indirectly by the primary of a
38kW
fully-modulating condensing boiler in the room below the cylinder. Hot
water
is circulated to the taps by means of a secondary pump. Because the
system
is unvented, the hot water is also at a pressure of about 2.5 bar.

Bronze pump needed will (cost will equal total of all the other pumps).
8-(


Thanks, Ed. Maybe I'll lay the pipe for the secondary loop and only add
the
pump later if the dead legs are a big problem.

Grundfos make:

1. a dedicated secondary circulation pump for ~£100.
2. a booster pump for ~£80.

The booster can be used with a pipe stat.

In article ,
IMM wrote:
Typo. should be.. Make sure the cupboard is well sealed and not
flimsey. You make need draught strip on the doors to prevent sounds
getting out. It does work.

Are you absolutely certain the maker allows this boiler to be fitted in
what would amount to an air sealed cupboard?

--
*Therapy is expensive, poppin' bubble wrap is cheap! You choose.

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

"Dave Plowman (News)" wrote in message
...
In article ,
IMM wrote:
Typo. should be.. Make sure the cupboard is well sealed and not
flimsey. You make need draught strip on the doors to prevent sounds
getting out. It does work.

Are you absolutely certain the maker allows this boiler to be fitted in
what would amount to an air sealed cupboard?

If you know anything about boilers, which you don't, they can. Air from
outside cools the inside as it enters. Now you know and I'm sure you will
forget immediately due to lack of focus.

In article ,
IMM wrote:
Are you absolutely certain the maker allows this boiler to be fitted in
what would amount to an air sealed cupboard?

If you know anything about boilers, which you don't, they can. Air from
outside cools the inside as it enters.

I'd suggest you catch up on reading the other threads since you've been
away. Without your rubbish to wade through it won't take as long.

Now you know and I'm sure you will forget immediately due to lack of
focus.

I'd take advice from the maker any time before the likes of you.
How's the hacksaw?

--
*Taxation WITH representation ain't much fun, either.

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

On Wed, 08 Dec 2004 10:08:36 +0000, John Aston wrote:


This is similar to a system I installed a couple of years ago. with a 170L
HWC and a Keston C40 (that's about 37kW output but runs at about 35kW due
to service main inadequacy). It works fine. Except I used a 5-way S-plan
and no UFH.


Ed, how do you rate the C40? I'm intending to buy this boiler and Keston's
Spa 300L cylinder.

We had a number of problems mostly that the gas valve kept getting choked
with a fine dust from the old 1" supply pipework (Yes I did blow the pipe
through before reusing it), replacement of thge pipe with new 28mm stuff
put an end to those problems.
After the first year when I removed the burner the top HE tube was
distorted which was replaced under warranty.

The design is the same as the Celsius 25 just bigger. It is not as quiet.
The same money nearly gets you 2 C25s which space permitting would be the
way I would go in future just because
a) there is in built redundancy.
b) 7-50kW output (cf 11-37kW).
c) quieter.


Since this is a sealed primary what does the 'top up' unit mean?


I was going to use it to add inhibitor to the heating system.

Is this essentially a built in funnel with a valve?




The water in the cylinder is heated indirectly by the primary of a 38kW
fully-modulating condensing boiler in the room below the cylinder. Hot
water
is circulated to the taps by means of a secondary pump. Because the
system
is unvented, the hot water is also at a pressure of about 2.5 bar.

Bronze pump needed will (cost will equal total of all the other pumps).
8-(


Thanks, Ed. Maybe I'll lay the pipe for the secondary loop and only add
the pump later if the dead legs are a big problem.

Well in relation to the multi thousand price ticket another £150 is not a
relatively big deal.

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

Ed Sirett wrote:
On Wed, 08 Dec 2004 10:08:36 +0000, John Aston wrote:

Ed, how do you rate the C40? I'm intending to buy this boiler and
Keston's
Spa 300L cylinder.

We had a number of problems mostly that the gas valve kept getting
choked
with a fine dust from the old 1" supply pipework (Yes I did blow the
pipe
through before reusing it), replacement of thge pipe with new 28mm
stuff
put an end to those problems.
After the first year when I removed the burner the top HE tube was
distorted which was replaced under warranty.

The design is the same as the Celsius 25 just bigger. It is not as
quiet.
The same money nearly gets you 2 C25s which space permitting would be
the
way I would go in future just because
a) there is in built redundancy.
b) 7-50kW output (cf 11-37kW).
c) quieter.

Unfortunately, the C25 doesn't have weather compensation. Nor does it
have two switched live inputs (dual flow temperatures for hot water and
central heating). The C40 has both these features and I need them both.

Since this is a sealed primary what does the 'top up' unit mean?


I was going to use it to add inhibitor to the heating system.

Is this essentially a built in funnel with a valve?


To quote from the HVCA's Domestic Heating Design Guide:

"The top-up unit is connected to the highest part of the system and is
fitted with a double check valve assembly and automatic air eliminator.
The unit, which has a water capacity of about three litres, is topped
up manually when the water level drops. It is also useful as an
indicator of leaks in the system. It should be connected either to the
return side of the radiator distribution pipework or to the return side
of the primary domestic hot water circuit.

The commissioning of the system is greatly simplified when a top up
unit is installed as initial pressurisation is unnecessary."
Cheers,
John Aston

On Thu, 09 Dec 2004 15:32:45 -0800, denbigh197 wrote:

=
The design is the same as the Celsius 25 just bigger. It is not as
quiet.
The same money nearly gets you 2 C25s which space permitting would be
the
way I would go in future just because
a) there is in built redundancy.
b) 7-50kW output (cf 11-37kW).
c) quieter.

Unfortunately, the C25 doesn't have weather compensation. Nor does it
have two switched live inputs (dual flow temperatures for hot water and
central heating). The C40 has both these features and I need them both.

I accept these points.

Note that the C40 is set up for
using a 70C-50C design out-of-the-box so that you will only get 70 flow
when the weather is very cold outside. On mild days you may well find the
boiler wants to run at 50C (flow) even when the boler control is turned up
fully. This may or may not bother you. It can also be changed.


Since this is a sealed primary what does the 'top up' unit mean?


I was going to use it to add inhibitor to the heating system.

Is this essentially a built in funnel with a valve?


To quote from the HVCA's Domestic Heating Design Guide:

"The top-up unit is connected to the highest part of the system and is
fitted with a double check valve assembly and automatic air eliminator.
The unit, which has a water capacity of about three litres, is topped
up manually when the water level drops. It is also useful as an
indicator of leaks in the system. It should be connected either to the
return side of the radiator distribution pipework or to the return side
of the primary domestic hot water circuit.

The commissioning of the system is greatly simplified when a top up
unit is installed as initial pressurisation is unnecessary."

There is no way I'd choose to fill a large system 3L at a time when the
mains filling loop is connected.
As far as I can tell it will be useful for
adding chemicals when the system is empty or at least at zero pressure,
there is no way it will top up the system once it is pressured.


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