RE: Condensing boilers & microbore pipe

["Neil Ball" <neilball@xxxxxxx>]

-----Original Message-----
From: Simon Rafferty [mailto:simonr@xxxxxxx]=20
Sent: Saturday, November 29, 2003 18:11
To: ukha_d@xxxxxxx
Subject: Re: [ukha_d] Condensing boilers & microbore pipe


<snip>=20
More expensive systems like TREND can cope and compensate for a thermal
gradient across a building as walls become warmed via sunlight at different
times of day thus inputting varying amounts of heat into different zones,
e=
g
easterly facing rooms may require less heat in the morning and more in the
evening. Beyond this you can link in multiple zoning for heating using
shun=
t
valves and pumps coupled to smart thermostats that set back to a lower
temperature either at night in various zones or when they are not occupied.

On a domestic scale savings are small 10 - 20% max. But we looked at an
installation in a hotel in Eire that was linked to the booking computer.
Th=
e
computer booked rooms a floor at a time and reduced the heat to the floors
that were unoccupied. Coupled with a smart thermostat in each room so that
only rooms that were occupied were heated evening and morning time using
solenoid operated valves. This saved the hotel 65% of its heating bill in
the first year and it paid for the BEMS in 11 months !!!!!
For a simple system have a look at Danfoss Randle
http://www.danfoss-randall.co.uk/default.asp
this is a boiler management
device. If you want to see a full blown BEMS check out
http://www.trend-controls.com/General/English.nsf/Docs/Homepage
we install
and commission quite a few of these systems in everything from football
grounds and sports statdia through office blocks and factories. Next time
you go into B&Q warehouse have a look around, they use them in most of
thei=
r
buildings.

<snip>
=20
=20
Sorry Simon, but I disagree. The savings potential for BEMS in domestic
environments is certainly there because traditional stats and programmers
are so unsophisticated. But in my view BEMS is a commercial controls
packag=
e
that is wholly inadequate for use by non-technical users and therefore in
n=
o
way suitable for domestic installations. The other problem is that the
performance of the system relies entirely on the commissioning engineer
tha=
t
writes the strategy for the installation, and if the strategy is poor then
the control performance will be equally poor. The final problem is cost -
the BEMS equipment requires an enclosure and switchgear as well as
specialist programming and installation which means even a basic system
would probably cost more than =A31000, probably 10 times the cost of the
ba=
sic
controls it will replace. Factor in the savings and you would have a simple
payback of say 10 years, and that excludes the ongoing costs of ownership.
What is really needed is a pre-programmed controller that delivers the
required energy saving strategies in a package that offers an intuitive
use=
r
interface so everyone can use it. It also needs to be simple to install and
set up so that any competent heating engineer can fit it, and be
cost-effective as an installed package to encourage take up. For domestic
systems then the DCD controller looks promising , and I imagine that the
th=
e
offerings from Honeywell & Siemens etc will start to become more
popular as
time goes on as well.
=20
Neil B.


[Non-text portions of this message have been removed]