Vacuum Pumping; Leakage Detection - Toyotomi TRN-828ZR User Manual

Vacuum pumping

Use vacuum pump
1. Remove the valve caps on the
liquid valve and gas valve and
the nut of refrigerant charging vent.
2. Connect the charging hose of
piezometer to the refrigerant
charging vent of gas valve and
then connect the other charging
hose to the vacuum pump.
3. Open the piezometer completely
and operate for 10-15min to check if
the pressure of piezometer remains
in -0.1MPa.
4. Close the vacuum pump and maintain
this status for 1-2min to check if the
pressure of piezometer remains in -0.1MPa.
If the pressure decreases, there may
be leakage.
5. Remove the piezometer, open the
valve core of liquid valve and gas
valve completely with inner hexagon
spanner.
6. Tighten the screw caps of valves and
refrigerant charging vent.
7. Reinstall the handle.

Leakage detection

1. With leakage detector:
Check if there is leakage with leakage detector.
2. With soap water:
If leakage detector is not available, please use soap water for leakage detection. Apply soap
water at the suspected position and keep the soap water for more than 3min. If there are air
bubbles coming out of this position, there's a leakage.
liquid valve
gas valve
refrigerant
charging vent
nut of refrige-
rant charging
vent
47
piezometer
valve cap
vacuum pump
inner hexagon
spanner
close
open
Lo Hi
GB