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It is important that the roof can bear the load of the HVAC equipment.
“These designs are then done – with
difficulty at times – to facilitate what is
presented,” he says.
Morne Meyer, business development
manager for Systems and DVM at Fourways
Airconditioning, says that a key function of
a mechanical engineer is to identify the
right ‘type’ of system that complements the
building structure. “The HVAC system plays
such an intricate role in building structures
these days and a lack of planning
considerably limits the options availab le to
the mechanical engineer,” he says.
In instances where the HVAC design is
complex, input for plant room space and
ceiling void space is discussed and
considered during the architectural design
phase. “There are many options available
from a system type solution to HVAC
designers and installers. However, the
system design generally determines the
void space required or vice versa,”
says Cramer.
As construction moves into the green
space, being energy efficient is a
prerequisite from clients. “Because of this,
architects incorporate new energy efficient
building methods and make use of greener
and more energy efficient products
available in the market,” says Cramer.
Easier said than done
Failing to incorporate the HVAC into the
initial design can cause many problems –
and not just for contractors. “Too often
engineers are forced make HVAC systems
work that were never designed or intended
for a specific building structure. Therefore,
the product ends up taking the blame when
it does not work,” says Meyer.
Some issues that concern HVAC
contractors include having access into the
roof. Sometimes the plaster ceiling has
already been installed, and it may require
them to cut through or break the ceiling,
which of course causes damage. “There are
times during the construction phase with
fast-tracked programmes, where roof
structures are in place, but the sheeting or
tiles are not. Mutual respect by all trades
(including the roofing contractor) ensures
that damage to other trade works is not
done,” suggests Cramer.
Meyer explains that sometimes the
roofing contractor may damage the existing
HVAC system by either damaging piping
(gas or water) or ducting. “In both cases it
impacts the whole HVAC system greatly and
it can be very costly to repair. More so in the
case of chilled water systems because in
most cases you need to repair the ceilings,
furniture and piping,” he says.
“Some poor installations – where HVAC
contractors have cut corners to save costs
– highlight hideaway air conditioners that
do not have return air ducting. The air is
supplied into the room, but the air is
returned to the air conditioner from the hot
(or cold air in winter) ceiling void. This adds
excessive load to the air conditioner,
making it ineffective and expensive to run,”
Parry explains.
Drainage is a big concern on any
structure. The system needs to drain the
condensate collected in the drip-tray on the
RESIDENTIAL // COMMERCIAL // INDUSTRIAL
FEBRUARY 2018
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