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7.5.1 - Pressure switch settings
Cut-out
Cut-in
Reset
30SZ/SZV 004-011
High pressurestat
2700 kPa*
-
Manual
30SZ/SZV 018-036
High pressurestat
2700 kPa*
-
Manual
* Factory-fitted
WARNING: Alteration of factory settings other than the
design set-point, without manufacturer's authorisation, may
void the warranty.
If ethylene glycol is used in the system, the manufacturer must
be asked for permission to change the unit protection
parameters.
7.6 - Operating limits
These units have been designed to operate within the following
limits:
30SZ
Water
Minimum
Maximum
Evaporator entering temperature
+9°C
+16°C
Evaporator leaving temperature
+5°C*
+13°C
Condenser entering temperature
+16°C
+50°C
Condenser leaving temperature
+18°C
+55°C
* Operation down to 0°C leaving water temperature is possible with anti-freeze solution and
special control configuration by Carrier Service.
30SZV
Water
Minimum
Maximum
Evaporator entering temperature
+9°C
+16°C
Evaporator leaving temperature
+5°C*
+13°C
Condensing temperature at the de30°C
+60°C
* Operation down to 0°C leaving water temperature is possible with anti-freeze solution and
special control configuration by Carrier Service.
8 - GENERAL MAINTENANCE
ATTENTION: Before starting any servicing or maintenance
operation on the unit, make sure that the power supply has
been disconnected. A current discharge could cause personal
injury.
In order to obtain maximum performance from the unit special
attention should be paid to the following points.
8.1 - Electrical connections
The supply voltage should be within the limits permitted by the
compressor.
Ensure that there are no faulty contacts in the terminal blocks,
printed cicuits, contactors, etc. Make sure that all the electrical
connections are properly tightened, and that all the electrical
components (contactors, relays, etc) are firmly secured to the
corresponding rails. Pay special attention to the condition of
the connecting cables between the control elements and the
electrical box, and to that of the unit power supply cable.
Check the starting and running consumptions are within the
limits specified in the corresponding technical information.
8.2 - Hydraulic connections
Ensure that there is no water leakage in the system. Drain the
unit, if it is expected to be shut down for a prolonged period.
This operation is essential if temperatures are expected to drop
below freezing, and if no glycol solution is used.
Carefully clean the system water filter.