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SiUS091601EA
Control Specification
Part 4 Functions and Control
80
5.3 Controls at Mode Changing/Start-up
5.3.1 Preheating Control
Outline
The inverter operation in open phase starts with the conditions of the outdoor temperature, the
discharge pipe temperature, the radiation fin temperature and the preheating command from the
indoor unit.
Details
09/15 class
Outdoor temperature ≥ –2.5°C (27.5°F)
Control A (preheating for normal state)
Outdoor temperature < –2.5°C (27.5°F)
Control B (preheating of increased capacity)
Control A
ON condition
Discharge pipe temperature < 0°C (32.0°F)
Radiation fin temperature < 85°C (185°F)
OFF condition
Discharge pipe temperature > 2°C (35.6°F)
Radiation fin temperature ≥ 90°C (194°F)
Control B
ON condition
Discharge pipe temperature < 10°C (50.0°F)
Radiation fin temperature < 85°C (185°F)
OFF condition
Discharge pipe temperature > 12°C (53.6°F)
Radiation fin temperature ≥ 90°C (194°F)
12/18/24 class
ON condition
Discharge pipe temperature < Outdoor temperature x
A
+
B
Outdoor temperature <
C
Radiation fin temperature <
D
OFF condition
Discharge pipe temperature > Outdoor temperature x
A
+
E
Outdoor temperature >
F
Radiation fin temperature ≥
G
5.3.2 Four Way Valve Switching
Outline
The four way valve coil is energized/not energized depending on the operation mode.
(Heating: ON, Cooling/Dry/Defrost: OFF)
In order to eliminate the switching sound as the four way valve coil switches from ON to OFF when
the heating is stopped, the OFF delay switch of the four way valve is carried out.
Details
OFF delay switch of four way valve
The four way valve coil is energized for 160 seconds after the operation is stopped.
A
B
C
D
E
F
G
(°C)
(°F)
(°C)
(°F)
(°C)
(°F)
(°C)
(°F)
12 class
0/256
10
0
32
85
185
12
2
35.6
90
194
18/24 class 238/256
35
6
42.8
85
185
37
8
46.4
90
194
Summary of Contents for FTX-N Series
Page 18: ...SiUS091601EA 13 Part 2 Specifications 1 Specifications 14 Part 2 Specifications...
Page 198: ...Check SiUS091601EA 193 Part 6 Service Diagnosis 18 24 class R24538 1 2 3 4 Multimeter...
Page 201: ...SiUS091601EA Check Part 6 Service Diagnosis 196 18 24 class R24539 DC DC W V U...
Page 229: ...SiUS091601EA Piping Diagrams Part 8 Appendix 224 RXL15QMVJU RXL18UMVJU 3D100007 3D123368...
Page 230: ...Piping Diagrams SiUS091601EA 225 Part 8 Appendix RXL24UMVJU 3D107985A...