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© STULZ S.p.A. – all rights reserved EN/06.2016/i01
WPA ExPlOrEr OrIGINAl INSTrUCTIONS
4.2 Intended use
This chiller is intended for the chilled water production and for the chilled water control. The
chiller is designed for outdoor installation on the roof of a building or at the ground level. Any
use beyond this is not intended. STULZ is not liable for any damage resulting from such misuse.
The operator alone bears the risk. The chiller must not be used for the warming of water, even if
it is equipped with the free cooling functionality.
4.3 Chiller Design
4.3.1 General
The chillers of the Explorer WPA series with scroll compressors exist in 4 construction sizes
which differ by their dimensions and cooling capacity. The chiller consists of two separate refrig-
erant circuits with two or three hermetic scroll compressors in each circuit, a single plate heat
exchanger or shell & tube evaporator, air cooled condensers and an electronic expansion valves.
After assembling the chiller each unit is pressure tested, evacuated and fully factory charged
with R410A and oil in each of the independent refrigerant circuits. The end of line test also
includes an operational test with water flowing through the evaporator to ensure that each
refrigerant circuit operates correctly.
4.3.2 Versions
The standard version for air cooled chillers with scroll compressors has a unit designation
which takes the following pattern: WPA _ _ _ SCN _ . There are two more versions which will be
described in the following.
Free Cooling Version
The free cooling version is available for the models WPA 060 to WPA 110. This Version addi-
tionally contains free cooling coils positioned directly in front of the condensers and therefore
in V-shape. Please be aware that there is a difference in the design between chillers with two
V-modules and three V-modules.
Two V-modules: The base version of the chillers WPA 060, WPA 070, WPA 080 has two V-mod-
ules and so the free cooling version has. The free cooling coils are positioned directly in front of
the condensers.
Three V-modules: The base version of the chillers WPA 080, WPA 090, WPA 100 has two
V-shape modules but the free cooling version has three. These chillers have the same cool-
ing capacity as the base version. To increase the surface of the free cooling coils there is one
V-shape module only consisting of the free cooling coils (not equipped with condensers).
During free cooling mode a motor-driven 3-way-valve directs the water volume completely
through the free cooling coils.
Each free cooling chiller is equipped with an hydronic group that consists of one storage tank
and at least one pump.
low noise version
With the low noise version of the Explorer WPA chillers you have the possibility to reduce the
noise emissions to up to –10dB.
