Samsung AM072BXV Series Service Manual page 273

Piping Diagram
7-3 Functions (cont.)
7-3-2 Control (cont.)
7-3-2-6 Indoor unit control (cont.)
Electronic Expansion Valve(EEV) Control
▪ Purpose
General control: Maintain the amount of refrigerant flowing into the indoor units at the appropriate level.
Inactive indoor unit control: Prevent insufficient refrigerant due to refrigerant stagnating in the piping connected to inactive
indoor units.
▪ Concept
General control: Control is performed with the superheat degree in cooling mode. In heating mode, control is performed
with the subcooling degree.
Inactive indoor unit control: The gas pipe is kept open slightly in heating mode to prevent refrigerant from stagnating in the
piping.
▪ Control specifications in detail
∙ Condition(s) required to use modes
- General control : Thermos on indoor units are on
- Inactive indoor unit EEV control: (Comp OFF) or (Comp ON and Indoor unit Thermo-OFF)
∙ Operation specifications
- General control: Control is performed with the superheat degree at the exit of indoor heat exchanges in cooling mode. In
heating mode, control is performed with the subcooling degree.
- Inactive indoor unit EEV control: Control is performed as shown in the following table.
Outdoor unit operation
Indoor unit operation
(Auto) cooling /
Dehumidification /
Fan
(Auto) heating
* Note 1 : Control of inactive heating units (lower noise/general)
Outdoor unit for first priority
outdoor unit
0℃ or lower
Above 0℃
Cooling
Heating
Samsung Electronics
Cooling
Thermo On Cooling EEV control
Thermo Off 0
Operation On Heating EEV control
Operation Off 0
CAM
80
80
Gas
Condensed liquid
Hot gas
Condensed liquid
COMP ON
COMP stops
Heating
Note 1*
Note 1*
EDM high-head
130
120
COMP OFF
COMP stops
- 3 min 3 - 5 min
0 0
0 0
35 35
35 35
EDM general
COMP stops
5 min elapses
35
35
35
35
200
180
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