General Functionality ESIE05-032–18 Part 2 – Functional Description312451.13 Pump Down OperationOutline Whenever the units need to be moved or removed, perform a pump-down operation beforedisconnecting the field piping. By performing a pump-down operation, all of the refrigerant will becollected in the outdoor unit.ProcedureCautions P Pressing the pump down switch (BS1) on the outdoor PCB may cause the outdoor and indoor fanto start operating automatically.P Be sure to open the stop valves after the pipe work has been finished. Be sure not to operate theunit with closed stop valves, or the compressor may brake down.Procedure Precautions1 Start "Fan only operation" from the remotecontroller.Confirm that both the liquid and gas stopvalves are open.2 Push the pump-down button BS1 on theoutdoor PCB.Compressor and outdoor fan will startautomatically.3 Once the operation stops (after 3~5 min-utes) close the liquid stop valve first andthen the gas stop valve.After the "Pump Down Operation" hasbeen finished the wired remote controllerscreen may be blank or show "U4" errorindication.It will not be able to start the unitfrom the remote controller without switch-ing OFF the power supply first.Make sure the stop valves are openedbefore restarting the unit.
