PROJECT
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The outdoor units located outside in a ‘hidden’ open room.
The simple room thermostat controlling the room temperature in the kitchen.
There were four in-wall distribution manifolds
installed and connected to the underfloor
water piping system. The Rotex Protect Integril
polystyrene sheet system was installed, into
which the PEX piping for carrying the hot and
cold water was installed, which heats up the
floor screed. A minimum of 50mm of screed
was used on top of the 45mm pipe as well as
high- and low-density polystyrene system.
The two heat pumps can be controlled remotely
via the Rotex mobile app. Which means the
heating, cooling, and hot water temperature can
be controlled from anywhere in the world!
CHALLENGES
The challenge is to ensure the integrity of
the pipe after the underfloor water piping is
installed and put under pressure whilst the
floor screed is laid. The system has to remain
under pressure until final handover, otherwise
the pipes could be compromised and then the
floor would have to be dug up and the pipes
repaired. This was not the case by connecting
www.plumbingafrica.co.za
the underfloor water system to the main water
throughout the construction.
ALL ABOUT EFFICIENCY
The system reduces the cost of heating a
house using electricity. This system was
designed with a heat load of 60W/m 2 due
to the design of the house, which has wall
insulation, good north-facing orientation,
and double glazing, compared to
electrical underfloor wire heating that
uses 100W/m 2 . The heat pump has a
coefficient of performance (COP) of
3.5 and this gives a consumption of only
15W/m 2 . This means the system uses a
quarter of the electricity required by the
electrical underfloor heating.
It is worth noting that the thermal store losses
are only 1°C per 24 hours.
In the end, everything came together well,
and the client was “over the moon” with the
end-result. PA
August 2018 Volume 24 I Number 6