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EN/05.2019 © STULZ GmbH – all rights reserved
CYBERHANDLER 2 INSTALLATION, OPERATION AND MAINTENANCE MANUAL
When the vacuum operation has been completed the refrigerant circuit must be filled by the
Schrader valve with the rated quantity of R410A refrigerant (available on the unit nameplate),
following the general rules here below:
• Before the system is filled with refrigerant, it must be clean and dry inside.
• Because R410A is blend and scrolls have discharge check valves, systems should be
liquid-charged on both the high and low sides simultaneously to ensure a positive refrigerant
pressure is present in the compressor before it runs. The majority of the charge should be
placed in the high side of the system to prevent bearing washout during first-time start.
• The standing refrigerant bottle is connected to the suction side via a pressure gauge station.
The weight is noted shortly before filling. The specified amount of refrigerant is now added
when the system is operating. During filling the pressure in the refrigerant bottle will adjust
to that of the system. Filling is then no longer necessary. This can be seen by the icing up of
the bottle or by checking the pressure gauge. The bottle valve must then be closed until a
pressure increase has taken place which is above the suction pressure of the system. This
process can be accelerated if the bottle is wrapped in hot moist towels or it is placed in a
water bath at a maximum temperature of 50°C.
R410A is a binary blend. Take care that you add refrigerant in a liquid state, as the
ratio of the refrigerant components changes if one of the two compounds passes over
into the gaseous phase.
