Water Connections; Frost Protection; Evaporator Flow Switch And Chilled Water Pump Interlock (Units Without Hydronic Module) - Danfoss BW05 Installation, Operation And Maintenance Instructions

7.2 - Water connections

The diagrams on the following page illustrate a typical
hydronic installation. When the hydronic circuit is filled, use
the air vents to evacuate any residual air pockets.

7.3 - Frost protection

The BW05 units are designed to be installed under cover at
outside temperatures between +5°C and +40°C. Therefore
they do not include anti-freeze protection, as standard.
If the water piping is in an area where the ambient tempera-
ture can fall below 0°C it is recommended to install a trace
heater on the piping and to add an antifreeze solution to
protect the unit and the water piping to a temperature of 10
K below the lowest temperature likely to be reached at the
installation site.
Use only antifreeze solutions, approved for heat exchanger
duty. If the system is not protected by an antifreeze solution
and will not be used during the freezing weather conditions,
draining of the cooler and outdoor piping is mandatory.
Damage due to freezing is not covered by the warranty.
IMPORTANT: Depending on the climatic conditions in your
area you must:
• Add ethylene glycol with an adequate concentration to
protect the installation up to a temperature of 10 K
below the lowest temperature likely to occur at the
installation site.
• If the unit is not used for an extended period, it is
recommended to drain it, and as a safety precaution
add ethylene glycol to the heat exchanger, using the
heat exchanger water entering purge valve connection.
At the start of the next season, refill the unit with water
and add an inhibitor.
• For the installation of auxiliary equipment, the instal-ler
must comply with basic regulations, especially for
minimum and maximum flow rates, which must be
between the values listed in the operating limit table
(application data).
To avoid corrosion by differential aeration, the
complete heat exchange circuit must be charged with
nitrogen, if it is drained for longer than one month. If
the heat exchange fluid does not comply with the
recommendations, the circuit must immediately be
filled with nitrogen.
VUGFB102
7.4 - Evaporator flow switch and chilled water pump
interlock (units without hydronic module)
IMPORTANT: On BW05 units, the unit water flow switch
must be energised, and the chilled water pump interlock
must be connected. Failure to follow this instruction will
void the guarantee.
The flow switch is supplied, installed on the evaporator
entering water pipe and preset at the factory to cut out when
there is insufficient water flow.
Terminals 34 and 35 are provided for field installation of the
chilled water pump interlock (auxiliary contact for pump
operation to be wired on site).
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