Control Specification
SiUS071735EB
33
Functions and Control
2.3 Controls at Mode Changing/Start-up
2.3.1 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
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)
2.3.2 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.
Summary of Contents for FDMQ09RVJU
Page 12: ...SiUS071735EB 1 List of Functions Part 1 List of Functions 1 Functions 2 ...
Page 14: ...SiUS071735EB 3 Specifications Part 2 Specifications 1 Specifications 4 ...
Page 125: ...SiUS071735EB Check Service Diagnosis 114 15 18 24 class R25105 1 2 3 4 Multimeter ...
Page 127: ...SiUS071735EB Check Service Diagnosis 116 15 18 24 class R20704 W V U DC_P1 DC_N1 ...
