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The retail offerings cater
for the students.
coefficient of performance [COP]. What we’ve done is
to put ducts on the exhaust side of the air exhausts to
take the cold air away from the unit, so you don’t get a
short circuit with the air cycle in Block B. In Block A, the
air exhausts directly out of the building via the basement
exhaust fans.”
No dead legs
“We made sure that there is a constant flow of hot water,
and so you never get a dead leg by putting in a return
system, which conserves water. What we mean by a
dead leg is a volume of water that grows cold in a pipe,
which usually happens when the showerhead or mixer
is far from the hot water tank. Naturally, it wastes water.
With this system, there is never a dead leg. This system
is also more efficient as it brings the unused water back
here to be reheated.
All the PPR hot reticulation
is insulated in R1-material
as per SANS 10400-XA.
“What has resulted is a Delta T, which is the difference
between the hot water going out and the hot water
coming back, of less than 5°C,” he says.
The insulation is paramount, Elsey explains. “The
pipework is all insulated — if we don’t insulate it
properly with an R1-rated material, then all of this other
work we do is useless. An R1-rated material means that
you lose less than 1°C per hour in heat.
“So, it might be an older building, but we have installed
the very latest in heat pump technology.”
Elsey explains that both Blocks A and B are gravity-fed
systems from roof tanks. “Even engineers think that