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135
Send oil return signal
oil return begins
oil return over
60s
ref. eliminated
30s
Oil return frequency
auto frequency
Low frequency
Inverter compressor
auto frequency
350pulse(E)
running indoor PMV
auto angle
auto angle
120pulse(E)
80(E)
stopped indoor PMV
OFF angle 5(E)
OFF angle 5(E)
Outdoor motor
AUTO
AUTO (TC or ambient temp. control)
AUTO
running indoor motor AUTO
AUTO (set fan speed)
AUTO
stopped indoor motor STOP
STOP
STOP
4-way valve
OFF
OFF
OFF
MULTI:
D: Entering condition
When the compressor running frequency is lower than 58Hz (E) continuously for 8 hrs, the system
will enter oil return operation. In the course of mode changeover, manual unit stop or protective
unit stop, the time will be accumulative. After the compressor restarts up, the time will be counted
continuously. In a continuous 8 hrs, if the compressor running frequency is not less than 72Hz for
over 10 minutes continuously, the accumulative time will be cleared. Also after the heating
defrosting, the time will be cleared.
E: Procedure
Cooling mode: refer to “the oil return procedure in cooling mode”
Heating mode: refer to “the oil return procedure in heating mode”
F: The protection treatment in oil return operation
In the course of oil return, because of protection or abnormal unit stop, after the unit restarts up,
the time will not be cleared, the system will need another oil return operation. In the refrigerant
flow course in the oil return of cooling mode or after the oil return, and within 5 minutes after the
refrigerant being eliminated is over, the anti-freezed protection is invalid, and also the low voltage
protection is invalid. But the other protection is valid.
In the course of oil return from heating mode to cooling mode, if abnormal condition occurs or the
unit stops for protection, then the system needs not another oil return within 3 minutes after the
unit stops and it will start up directly, then to heating mode.
In the course of oil return from heating mode to cooling mode, the anti-freezed protection is null
and void, and the low voltage protection is null either. The other protection is valid.
Oil return procedure in cooling mode:
Summary of Contents for AB25S2SC1FA
Page 1: ...SYJS 04 2017 REV A Edition 2017 04 service manual R32...
Page 3: ...1 Part 1 General Information 1 Indoor outdoor unit models 2 2 Feature 3...
Page 23: ...21 5 Installation For AB25S2SC1FA AB35S2SC1FA 1 Installation procedure...
Page 24: ...22 AB25S2SC1FA AB35S2SC1FA AB25S2SC1FA AB35S2SC1FA...
Page 25: ...23...
Page 26: ...24...
Page 27: ...25 AB25S2SC1FA AB35S2SC1FA...
Page 28: ...26...
Page 29: ...27 For AD25S2SC1FA AD35S2SC1FA Installation procedure AD25S2SS1FA AD35S2SS1FA...
Page 30: ...28 AD25S2SS1FA AD35S2SS1FA AD25S2SS1FA AD35S2SS1FA...
Page 31: ...29...
Page 32: ...30 AD25S2SS1FA AD35S2SS1FA...
Page 33: ...31...
Page 38: ...36 21mm AD50S2SM1FA AD71S2SM1FA Unit model The size of drain opening...
Page 39: ...37...
Page 54: ...52 2 Dimension 1U71S2SM1FA 860 633 unit mm...
Page 91: ...89 R32 R32 R32 R32 R32 R32 R32 R32 R32 10 2 Read before installation...
Page 92: ...90 3 R32 R32 R32 R32 R32 R32 R32...
Page 93: ...91 R32 R32 R32 R32 R32 R32 R32 R32 10A HFC 410A...
Page 96: ...94 10 5 Air tightness test...
Page 97: ...95 R32 R32 10 6 Vacuuming...
Page 123: ...121 PCB 0011800410RA 1U71S2SG1FA Power module 0011800377C 1U71S2SG1FA...