Kaisai KMK-60RY1, Service Manual

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M thermal Split
18 202004
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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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Part
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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 Split Engineering Data Book Part
3, 8.5 “COOL MODE SETTING Menu” and Part 3, 8.6 “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
Figure 3-3.1, Figure 3-3.2.
Figure 3-3.1:
KHA-06RY1
compressor startup program
1
when ambient temperature is above 3°C
38rps
Target rotation speed
Compressor rotation speed (rps)
Time (s)
32rps
42rps 56rps
66rps
70rps
40s
60s
40s
40s
40s
120s
82rps
120s
Notes:
1. Once the first, 40-second stage of the program is complete, the program proceeds to the subsequent stages in a step-by-step fashion and exits when the
target rotation speed has been reached.
Figure 3-3.2: KHA-06RY1 compressor startup program
1
when ambient temperature is at or below 3°C
38rps
Target rotation speed
Compressor rotation speed (rps)
Time (s)
0
32rps
42rps 56rps
66rps
70rps
40s
90s
60s
40s
40s
240s
82rps
240s
36rps
90s
Notes:
1. Once the first, 40-second stage of the program is complete, the program proceeds to the subsequent stages in a step-by-step fashion and exits when the
target rotation speed has been reached.
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