Push Pull Operation - JAVAC XTR-PRO-DV Safety Instructions & Operation Manual

5.4 PUSH/PULL OPERATION
5.4.1 The PUSH PULL method is used to move a large amount of liquid refrigerant from the system
being serviced to the recovery cylinder without passing it through the compressor. This method is
only useful when more than 7 Kg of liquid is known to be in the system and it can be easily isolated.
DO NOT ATTEMPT the PUSH PULL process unless you are sure of the situation.
5.4.2 Connect the refrigerant hoses as shown below. Addition of a SIGHT GLASS in line between the
system being serviced and the recovery cylinder can be an important aid to determine when all the
liquid has been transferred and only vapour remains.
5.4.3 This process uses the PULL from the exhausted recovery cylinder and the Discharge PUSH
from the recovery unit to move the liquid refrigerant. Rates in excess of 5 Kg per minute can be
achieved by this procedure.
5.4.4 The SCALE is required in this process to ensure that the cylinder is not overfilled. The cylinder
shutoff switch, if used, would stop the compressor but could not guarantee that additional refrigerant
flow would cease because of the dynamics of the system, thus possibly overfilling the cylinder.
SET-UP PROCEDURE FOR PUSH/PULL METHOD
LIQUID
FILTER
CYLINDER
WITH
CT-OFD
SCALE
VAPOUR
SYSTEM
RECOVER
OPEN
LIQUID
V3
OPEN
VALVE POSITIONS FOR PUSH/PULL METHOD
RECOVERY UNIT
RECOVERY UNIT
POWER
SOURCE
VAPOUR
VALVE POSITIONS DURING PURGE OPERATION
LIQUID
V2
PURGE
CYLINDER
CLOSE WITH
CT-OFD
V1
PURGE CLOSE
SCALE
LIQUID
VAPOUR
CYLINDER
SCALE
FILTER
POWER
SOURCE
RECOVER
OPEN
V3
OPEN
VAPOUR
LIQUID
SYSTEM
CYLINDER
WITH
LIQUID
CT-OFD
SCALE
VALVE POSITIONS FOR PUSH/PULL METHOD
V2
PURGE
V1
PURGE CLOSE
RECOVERY UNIT
RECOVERY
FILTER
POWER
SOURCE
OPTIONAL
CONNECTION
TO SYSTEM
RECOVER
OPEN
V3
VALVE POSITIONS DURING
13
POWER
SOURC
VAPO
OPEN