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CAUTION: R-22 oils are absolutely not compatible with R-407C.
Recommended oil:
R-22 semi-hermetic compressors:
-
Mineral oil, Carrier specification No. PP 33-02
-
Suniso 3 GS (Sun Oil Co)
-
Capella WF 32-150
-
Clavus G 32 (Shell Oil Co)
-
Gargoyle Artic (Mobil Oil) - original charge
R-407C semi-hermetic compressors:
-
Polyester oil without additives (POE), Carrier
specification No. PP 47-26
-
Polyolester Mobil Oil EAL 68
WARNING: All fixing devices and fittings which may have
been removed during servicing must always be replaced upon
completion of the work and before restarting the unit.
Tightening torques to be applied
Description
Diameter, mm
Torque, Nm
Discharge valve
M16
135-140
Cylinder head
M12
75-87
Suction and liquid line flange
M12
75-87
Suction valve
M16
135-140
Compressor protection circuit board (STARTERGUARD)
The purpose of this card is to monitor the compressor
operating environment, in particular:
•
the crankcase heaters
•
the contactors
•
the part winding start timer
•
the control wiring between these components
The status of the controlled components is displayed via three
different-coloured LEDs:
•
Green LED: correct operation
•
Orange LED: signals that the magnetic loop of the card
has detected the presence of a current, either in the
compressor crankcase heater or in the compressor motor.
If the green and orange LEDs are illuminated together,
this indicates that there is no fault.
•
Red LED - fault related to:
-
the heater, if the orange LED is not lit
-
the contactor or the power line of the compressor
motor, if the orange LED is lit
If a fault is detected, the compressor is shut down.
Power supply and resetting:
The STARTERGUARD card uses 24 V AC
±
10%, 50 Hz or
60 Hz. When a fault occurs, the 24 V supply must be
interrupted and then restored, in order to reset the card. The
green LED lights up.
Oil pressure safety switch
38AJ/AZ 014-074 units have an oil pressure safety switch
which shuts down the unit if the oil differential pressure at the
compressor either fails to reach or to be held at the proper level.
To restart the unit press the manual reset button on the main
circuit breaker and set the fan switch to OFF and then to ON.
NOTE: Damage resulting from failure to follow these
instruction is not covered by the product warranty.Compressor
motor protection
Compressor protection devices
Circuit breaker
Calibrated, thermo-magnetic, manually reset circuit breaker
protects the compressors against locked rotors and overloads. It
also offers protection against excessive current draw up to the
trip capacity given in the wiring diagram.
WARNING: Never bypass a circuit breaker or increase its
setting. If a circuit breaker trips, find out why it has done so
and correct the problem before resetting the breaker.
Discharge gas thermostat DGT - 38AJ/AZ 018-074
A sensor in each compressor discharge line opens to shut down
the compressor if the discharge gas temperature exceeds the
preset level.
Cut out 146
°
C
Cut in 113
°
C
Crankcase heater
Each compressor is fitted with an electric resistance crankcase
heater which prevents any absorption of refrigerant by the
compressor lubricating oil when the compressor is shut down.
Each heater is held in place by a screw clip which must be
secure. Prolonged exposure of the heater to air will result in its
destruction. The heater is energized when the compressor is
switched off.
WARNING: Never open or disconnect any switch or circuit
breaker which will cut the supply to the heaters, unless the unit
is to be shut down for lengthy service or repair or for a
seasonal shut down. In all cases the heater must be energised
for at least 24 hours before a compressor is restarted.
Condenser coil
We recommend, that finned coils are inspected regularly to
check the degree of fouling. This depends on the environment
where the unit is installed, and will be worse in urban and
industrial installations and near trees that shed their leaves.
For coil cleaning proceed as follows:
•
Remove fibres and dust collected on the condenser face
with a soft brush (or vacuum cleaner).
•
Clean the coil with the appropriate cleaning agents.
We recommend TOTALINE products for coil cleaning:
Part No. P902 DT 05EE: traditional cleaning method
Part No. P902 CL 05EE: cleaning and degreasing.
These products have a neutral pH value, do not contain
phosphates, are not harmful to the human body, and can be
disposed of through the public drainage system.
Depending on the degree of fouling both products can be used
diluted or undiluted.