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Traditional quick-response or
mixed systems do not need to waste
energy by preheating for hours
before occupation; nor will they waste
energy by continuing to provide heat
when the sun comes out. We need a
simple, easy to maintain, adaptable
and genuine low energy solution. If
you go down the ground source heat
pump route, you do of course need
a designer who understands that
heat pump efficiency is related to
flow temperature and undertakes the
design accordingly, including direct
weather compensation.
Over the last few years I’ve been
pleased to display to my employer,
through energy monitoring, how
school heating systems that my
mechanical team have designed in
this way have lower heating energy
consumption than comparative new
buildings with slow-response heating
systems.
Geoff Carter
Accidents waiting to happen?
I read with interest the two articles in
the February Journal, ‘Fit for purpose’
and ‘Digging deep for a solution’
(pages 24 and 47). As an industry
we face huge challenges to embrace
new technologies and integrate
them into projects – essential if we
are to deliver low energy, low carbon
developments.
However, new entrants to
our industry face a health and
safety challenge, too. Indeed, the
photograph of ‘the borehole array’
on page 48 demonstrates this
concern. The photo shows borehole
covers removed, with no physical
barrier put in place to provide
pedestrian or vehicle access control
to the area.
From the photograph, I suspect
the project is at commissioning/
fit-out phase. But it is still cause for
concern – even though, statistically,
33% of accidents occur on building
sites during the final stages of
completion/handover.
Andy Sneyd
ciBse.coM
ReadeRs’ Poll
Each month we will be
posing a question to
readers at our website,
www.cibsejournal.com
Last month we asked:
Will Britain achieve the policy
goal of all new homes being
zero carbon in 2016?
Yes
no
An overwhelming majority of
respondents (84%) said ‘no’
to this question, with 16%
saying ‘yes’.
This month the question is:
Within project teams, are
building services engineers
the best people to take a lead
on pushing for sustainable
design and construction?
Visit www.cibsejournal.com
to have your say.
Manufacturer’s
Viewpoint
The construction industry
seems to be beset by
deadlines. As legislation on
energy efficient and sustainable
buildings mounts, it is easy to put
actions on the backburner until a
deadline is looming closely.
However well this might work, it
is not always the most costeffective
option in the long or
short term.
The air conditioning sector
has already passed an important
deadline. From January 2010
it became illegal to use virgin
HCFC refrigerants, such as R22.
This rule is part of the Ozone
Depleting
Substances
Regulations
(ODS) which
were introduced
in the UK in
October 2000.
This rule means
that air conditioning
systems using R22 are
now obliged to operate
only on recycled
or reconditioned
refrigerant. The next
deadline under ODS is
1 January 2015. At this
point, all HCFC refrigerants will be
illegal. The ODS rules also specify
that any personnel handling
refrigerants must be properly
qualified and certified.
With four years to go, the
phase-out of R22 might not seem
like a pressing problem, but the
effects of ODS are already being
seen in the market. Only around
10% of the required levels of R22
are being returned to suppliers
for recycling, which is pushing
up the price of this refrigerant to
almost three times its level before
the ban.
So waiting to deal with R22
systems is a costly decision.
This is especially true of
business-critical equipment.
What’s more, as the deadline
One option is
to convert an
HCFC system
to a different
refrigerant,
using drop-in
replacements, but
this will change the
system operation
opinion
The industry needs to prepare now for
the phase-out of HCFC gases, writes
Martin Fahey of Mitsubishi Electric,
sponsor of this column
approaches, demand for those
‘certified’ personnel and training
programmes will also increase
– and this seems likely to raise
those costs too.
Planning ahead need not be a
painful process. One option is to
convert an HCFC-based system
to a different refrigerant. This can
be achieved by using ‘drop-in’
replacements. However, it is
important to bear in mind that
these will change the way an air
conditioning system operates,
can lead to reduced energy
efficiency and cooling capacity,
and have significant impact on
warranties and
operating costs
in the medium
and long term.
With three years
to plan, it is
possible to take
a more strategic
approach
and use this
opportunity
to consider
replacing
older systems
with modern
equipment. Not
only is this a more permanent
solution, it also offers the benefits
of greater energy efficiency and
lower carbon emissions from
modern equipment.
Whatever the decision, it is
important that end-users start to
form their strategies for dealing
with HCFC phase-out now. As
the deadline approaches it will
be important to be prepared for
the change, especially where air
conditioning is a business-
critical system.
SPONSORED BY
www.cibsejournal.com April 2011 CIBSE Journal 25