Eev Control - LG MULTI V Service Manual

1.3 EEV control

(1) Main EEV control
Main EEV operates with fuzzy control rules to keep the degree of super Heat(Superheat)
(about 3 ℃(37.4 ℉))at the evaporator outlet stable during heating mode
The degree of Superheat = Tsuction - Tevaporation
Tsuction : temperature at suction pipe sensor(℃,℉)
Tevaporation : evaporation temperature equivalent to low pressure(℃,℉)
(2) Subcooling EEV control(about 15 ℃(59 ℉))
Subcooling EEV works with fuzzy rules to keep the degree of Subcool at the outlet of subcooler during
cooling mode
The degree of Subcool = Tcondensation - Tliquid
Tliquid : temperature at outlet of subcooler(℃,℉)
Tcondensation : condensation temperature equivalent to high pressure(℃,℉)
(3) Avoiding excessive high discharge temperature : when main EEV opens some given opening and dis-
charge temperature is above 85 ℃(185 ℉) in heating operation, subcooling EEV may control the "sub-
cooling out temperature-evaporating temperature" to be some given difference.
- 19 -
Copyright © 2020 LG Electronics Inc.
All rights reserved. Only training and service purposes.
Function