Technical data

20
Filter-drier
The filter-drier keeps the circuit clean and free of moisture. The
sight glass indicates when it is necessary to change the cartridge
in the filter-drier. A temperature difference between the inlet
and the outlet of the filter-drier indicates fouling of the drier.
NOTE: The unit must run for at least 12 hours before it can
give an accurate indication, because only with the unit running
is the indicator in continuous contact with the refrigerant.
Liquid line service valve
This valve provides, in each circuit, a liquid refrigerant charging
port and, in conjunction with the compressor discharge line
valves, enables liquid refrigerant to be pumped to the high-
pressure side of the system.
Pressure switch setting
High pressure switch
The high pressure switch has fixed non-adjustable settings.
To check: Switch off the unit. Disconnect the fan power, until
the compressor shuts down. This should be at the cut-out
pressure indicated. When the pressure drops to the cut-in
setting, reset the switch.
Low pressure switch (electromechanical version)
This protects against loss of charge.
To check: Slowly close the suction shut-off valve and allow
the compressor to pump down. Do not allow the compressor to
pump down below 3 kPa. The compressor should shut down
when the suction pressure drops to the cut-out pressure, and
restart when it builds up to the cut-in pressure indicated.
Cut-out Cut-in
High pressure switch
30GH/GZ 009-013 2500 kPa 2150 kPa
30GH/GZ 015-035 2900 kPa 2200 kPa
Low pressure switch
30GH/GZ 009-035 50 kPa 150 kPa
(electromechanical control)
Optional hydronic kit
Pump
Verify the water flow rate, using the pump performance curves.
A decrease in the flow rate may be a sign of fouling of the filter
installed upstream of the pump or the hydraulic circuit itself.
Clean as necessary.
During the periodic maintenance check that the current draw is
within the operating range, in order to avoid bearing wear. Also
check the wear of the mechanical fittings.
Expansion tank
Ensure that the Hydroflow module pressure gauge does not
show a pressure drop. The nitrogen pressure can be adjusted
with the valve on the side opposite to the hydraulic connection.
Fan motor replacement
a) 30GH/GZ 009-013 units
Fan motors can be removed through the top of the unit.
Carefully follow the safety considerations and do not damage
the propeller. Label the wires when they are removed.
30GH/GZ 009-013 unit fan
b) 30GH/GZ 015-035 units
This presents no special problems. The work is done from
above the unit.
• Remove the grille with its support air duct assembly.
• Remove the fan shaft protection cap.
• Pull the fan from the shaft using a FACOM U35 or similar
hub puller
• Unscrew the fan motor fixing bolts. Remove only the
lower bolts to prevent the motor from falling.
• Withdraw the fan motor.
Installation is in reverse order. Take care not to damage the
plastic components when installing the fan and position the fan
to maintain a clearance of 170 + 0/+2
mm between the upper
edge of the fan and the upper edge of the volute. Tighten the
fan motor fixing bolts to a torque value of 9 Nm.
CAUTION: On unit sizes 30GH/GZ 015-035 the fan rotation is
counter-clockwise viewed from above.
30GH/GZ015-035 unit fan
Fan motor protection
All fan motors are protected by one thermo-magnetic circuit
breaker (30GH/GZ 009-025) or by two thermo-magnetic circuit
breakers (30GH/GZ 030-035).
Refrigerant circuit
Thermostatic expansion valve (TXV)
The function of the thermostatic expansion is to control the
flow of liquid refrigerant. The valve is controlled by a heat
sensitive sensor bulb in the suction line. It is factory-set to
maintain a superheat of 4 K. Never change the setting, unless
absolutely necessary.
MAXIMUM
CLEARANCE
80 mm + mm
0
2
MAXIMUM
CLEARANCE
170 + mm
0
2