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Basic Control
SiUS28-902_a
19
Function
2.3
Electronic Expansion Valve PI Control
Main Electronic Expansion Valve EV1 Control
Carries out the electronic expansion valve (Y1E) PI control to maintain the evaporator outlet
superheated degree (SH) at constant during heating operation to make maximum use of the
outdoor unit heat exchanger (evaporator).
The optimum initial value of the evaporator outlet superheated degree is 5°C (9°F), but varies
depending on the discharge pipe superheated degree of inverter compressor.
Subcooling Electronic Expansion Valve EV2 Control
Makes PI control of the electronic expansion valve (Y2E) to keep the superheated degree
(SH)
of the outlet gas pipe on the evaporator side for the full use of the subcooling heat exchanger.
SH = Ts - Te
SH : Evaporator outlet superheated degree (°F)
Ts
: Suction pipe temperature detected by thermistor
R2T (°F)
Te : Low pressure equivalent saturation temperature
(°F)
SH = Tsh
-Te
SH : Outlet superheated degree of evaporator (
°
F)
Tsh : Suction pipe temperature detected with the
thermistor R5T (
°
F)
Te : Low pressure equivalent saturation
temperature (
°
F)
Summary of Contents for SkyAir FCQ18PVJU
Page 1: ...Split System Air Conditioners SkyAir Inverter R 410A Heat Pump 60Hz P Series SiUS28 902_a...
Page 44: ...Other Control SiUS28 902_a 37 Function...
Page 81: ...SiUS28 902_a Troubleshooting by Remote Controller Troubleshooting 74...
Page 185: ...SiUS28 902 Precautions for New Refrigerant R 410A Precautions for New Refrigerant R 410A 178...