Commissioning; Leak, Pressure And Vacuum - Digitus DN-97332 User Manual

4. The power supply circuit breaker and fuse rating to meet the needs
of the unit.
5. If the monitoring cable, check the monitor cable is connected.
6. Check all cables, connectors have been tightened, without loosening
the fixing screws.

4. Commissioning

4.1. Leak, Pressure and Vacuum

1. After completion of all pipe connections, with a nitrogen leak
pressure test, the inflation pressure should≧ 3MPa, and from the
high and low pressure portion while charged with nitrogen until
equilibrium is.
2. After purged with nitrogen, 24 hours dwell time should be no
leakage, such as large temperature changes within 24 hours, since
the thermal expansion characteristics of the gas, there will be slight
changes in pressure, such as the temperature difference is 3℃,
Pressure changes ≤1%, should be normal, if the pressure change
value is exceeded, then the leak should be found to re-welding
pressure test.
3. After completion of leak, let go of the nitrogen gas in the system, the
vacuum pump to evacuate the system. After the system is evacuated
to an absolute vacuum of 100Pa, Paul negative 2h, if the pressure
does not rise then it is qualified.
Note
1. 3kW/5kW/7kW/12kW prefilled without refrigerant.
2. prohibited the use of oxygen or other gas tightness test.
3. the system leak charged nitrogen pressure plate unit cannot exceed
the nominal maximum working pressure. Even an increase of the
refrigerant pipe length.
If the connecting line between the indoor unit and the outdoor unit over
a certain distance needs to be added to the system to the refrigerant
system operation.
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