Kaisai 06RY1, Service Manual

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M thermal Mono
16 202008
Midea
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1 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 PCB digital displays and on the user
interface.
2. The system stops when the set temperature has been reached.
2 Standby Control
2.1 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 outdoor ambient temperature and the compressor on/off state. When the
outdoor ambient temperature is above 8°C or the compressor is running, the crankcase heater is off; when the outdoor
ambient temperature is at or below 8°C and either the compressor has been stopped for more than 3 hours or the unit has
just been powered-on (either manually or when the power has returned following a power outage), the crankcase heater
turns on.
2.2 Water Pump Control
When the outdoor unit is in standby, the internal and external circulator pumps run continuously.
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3 Startup Control
3.1 Compressor Startup Delay Control
In initial startup control and in restart control (except in oil return operation and defrosting operation), compressor startup
is delayed such that a minimum of the set re-start delay time has elapsed since the compressor stopped, in order to
prevent frequent compressor on/off and to equalize the pressure within the refrigerant system. The compressor re-
start delays for cooling and heating modes are set on the user interface. Refer to the Mono Engineering Data Book Part 3,
7.5 “COOL MODE SETTING Menu” and Part 3, 7.6 “HEAT MODE SETTING Menu”.
3.2 Compressor Startup Program
In initial startup control and in re-start control, compressor startup is controlled according to outdoor ambient
temperature. Compressor startup follows one of two startup programs until the target rotation speed is reached. Refer to
Figures 3-3.1, 3-3.2, 3-3.3 and 3-3.4.
Figure 3-3.1: 6kW to 12-16kW Compressor startup program
1,2
when ambient temperature is above 3°C
10
20
30
40
50
60
70
80
90
38Hz
40S
32Hz
60S
42Hz
40S
56Hz
40S
66Hz
40S
70Hz
120S
82Hz
120S
目标频率
时间
Hz
Figure 3-3.2: 8-10kW Compressor startup program
1,2
when ambient temperature is above 11°C
42Hz
90S 36Hz
60S
42Hz
40S
56Hz
40S
66Hz
40S
70Hz
40S
82Hz
120S
目标频率
时间
Hz
TIME
TARGET FREQUENCY
TIME
TARGET FREQUENCY
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