Projects
1
Martin Davis
2
Condenser water is circulated through a ring main pipe system
on the mall levels. The various shops are each provided with
tap-off valves into the main condenser water pipe ring in direct
proximity to the shop, enabling each tenant’s DX package units
to obtain its cooling water from the ring.
Two air-cooled heat pump chillers are installed in the
main cooling tower plantroom to introduce heat back into
the condenser water circuit for when there is a net heating
demand within the mall or if the condenser water temperature
drops too low.
RACA Journal
RACA Journal
1. The five Evapco cooling towers really tower a person, and
weigh over 25 tonnes each.
2. The heat pump chillers.
3. The induction jet fan for smoke clearance in the lower
parking area.
3
Shop/tenant air conditioning system
The DX package A/C units consist of an air-filter, refrigeration
circuit with compressor, evaporator and water-cooled
condenser, and supply air fan. Two types of units are
distinguished – for smaller shops, in-ceiling type A/C units
are installed, while the larger shops are provided with floor
standing, up-blow A/C units positioned in a plantroom within
the tenant-area.
The units supply filtered and conditioned air into the
shop via externally insulated galvanised sheet metal ducting
installed within the ceiling void. Air is deposited into the shop
via CAV type ceiling diffusers.
The return air passes through return-air grilles and a shop’s
common ceiling plenum space. The DX package A/C units are
energised from the tenant’s electricity distribution boards (DB),
and the energy consumed by these units is thus measured
and can be paid for directly by the tenant. The indoor air
temperature is controlled through a wall-mounted set point
adjuster that allows for individual temperature set point control.
30
RACA Journal I October 2020
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