Stop Operation; Standby Control - Sinclair SCV-750EB Service Manual

2 Stop Operation

The stop operation occurs for one of the following reasons:
1. Abnormal shutdown: in order to protect the compressors, if an abnormal state occurs the system makes a stop with thermo
off operation and an error code is displayed on the outdoor unit's PCB digital displays and on the user interface.
2. The system stops when the set temperature has been reached.
In order to prevent the compressor from starting and stopping frequently and to balance the pressure in the refrigeration
system, forcibly stop the compressor for 7 minutes before starting. (Except for special controls such as defrosting).

3 Standby Control

3.1 Crankcase Heater Control
The crankcase heater is used to prevent refrigerant from mixing with compressor oil when the compressors are stopped. The
crankcase heater is controlled according to the outdoor ambient temperature and discharge temperature. When the outdoor
ambient temperature is above 40°C, the crankcase heater is off; when the outdoor ambient temperature is below 35°C, the
crankcase heater is controlled according to discharge temperature.
3.2 Water Pump Control
When the outdoor unit is in standby, the circulator pump run continuously.
Ambient temperature < 35
Crankcase heater is controlled according to discharge temperature
Min (Tp1, Tp2) < 40
Notes:
1. Tp1: discharge temperature sensor 1;
2. Tp2: discharge temperature sensor 2.
Crankcase heater off
o
C Ambient temperature > 40
Crankcase heater off
o
C Min (Tp1, Tp2) > 50
Crankcase heater on
o
C
o
C
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