Pump Down - LG MULTI V Service Manual

4.2 Pump Down

This function gathers the refrigerant present in the system to ODU
Use this function to store refrigerant of system in ODU for leakage or IDU replacement.
Setting method
Close liquid service valve of each unit.
Refer the right side figures of this page and
open the proper valve by each system.
Power Reset after Master Unit
DIP switch setting (Refer to DIP switch setting page )
Press the red button (SW01C)
All IDU cooling operation
Note 2)
Low pressure
< 229 kPa(33.2 psi)
Power reset after DIP switch off
[Note]
If low pressure become under 307 kPa (blink), close the gas SVC V/V of all ODU immediately.
If low pressure descends below 229 kPa, the system turns off automatically. Close the gas SVC V/V immediately.
Caution
1.Use pump down function within guaranteed temperature range
IDU : 20~32 °C(68~89.6 °F)
ODU : 5~40 °C(41~104 °F)
2. Make certain that IDU doesn't run with thermo off mode during operation
3. Maximum operation time of pump down function is 30 min.
(in case low pressure doesn't go down)
Satisfy low
pressure target?
Yes
*Current low
Pump down completed
pressure
Press the red button
(SW01C)
IDU, ODU OFF
*Current low
pressure
No
Note 1)
*Current low pressure
under 307 kPa(44.5 psi)
(blink)
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Function
[Case 1] ODU Service Valve Setting
(for Heat Recovery System)
Close Close
Liquid High pressure Low pressure
Pipe Gas Pipe Gas Pipe
[Case 2] ODU Service Valve Setting
(for Heat Pump System)
Close Open
Liquid Gas No used
Pipe Pipe (Keep closed)
[Case 1] ODU Service Valve Setting
(for Heat Recovery System)
Close Close Close
Liquid High pressure Low pressure
Pipe Gas Pipe Gas Pipe
[Case2] ODU Service Valve Setting
(for Heat Pump System)
Close Close Close
Liquid Gas No used
Pipe Pipe (Keep closed)
Open
Close