LG ABNH186HLAC, Service Manual

Page: 126 / 175

130 Universal System Air Conditioner
Outdoor Units
1.3 EEV Control
1) The base(the first stage) open_degree’s establishment
The base open_degree is established [the standard open_degree classified by indoor_Type and capacity ]
that corrected to the indoor/outdoor Temp.
2) Starting Control (LEV target open_degree arrival process after starting Comp)
(1) LEV is arrived the previous decided open_degree within 30 seconds after starting COMP.
(2) The open-degree is increased to target_degree in proportion to Comp operation time.
❈
The starting control°Øs time is within 120 seconds after COMP operation
3) Normal Control
: The condensor's degree of superheat c Compressor Discharge-Temp. Control
(1) Cooling mode
In cooling mode, normal control regulates EEV pulse that continues to fixed value for Superheat Temp. of
the operating indoor unit.
(2) Heating mode
In heating mode. It is used the degree of superheat control that be regular the difference with Compressor
Suction pipe-Temp. (ACCUM) and pipe Temp. of outdoor_unit
The degree of superheat = Compressor Suction pipe_Temp. (ACCUM) – The pipe Temp. of outdoor_unit
(3) EEV control
a. Superheating control (Cooling Mode)
- Superheating : T superheating = Tout – Tin = 2°C
- LEV pulse up : T superheating > 2°C
- LEV pulse down : T superheating < 2°C
b. Target Temperature Control (Cooling mode)
- In case, outdoor temperature > 39°C
- Target superheating : T target = Tin = 18°C
- LEV pulse up
: T target < 18°C
- LEV pulse down : T target > 18°C
c. Target Temperature Control (Heating mode)
- LEV pulse up : T target > Tout
- LEV pulse down : T target < Tout
d. LEV pulse change Value
8 pulse (P1-P0 > 4°C)
4 pulse (4°C
≥
P1-P0 > 3°C)
2 pulse (3°C
≥
P1-P0 > 1°C)
Control subject : The pipe Temp. of outdoor_unit
T_Target : The pipe Temp. of indoo The degree of superheat
Control subject : The suction_pipe of indoor_unit
T_Target : The pipe Temp. of outdoo The degree of superheat