Kubota B1830, Workshop Manual, Page: 515 / 548

CABIN B1830,B2230,B2530,B3030, WSM
10-S10
(3) Vacuum Pump Adaptor
Objective of the Vacuum Pump Adaptor
1. After vacuum has been created in the air conditioning cycle,
when the vacuum pump is stopped, since there is vacuum in
hoses within the gauge manifold, the vacuum pump oil flows
back into the charging hose. If the refrigerant is refilled with the
system still in this state, the vacuum pump oil left in the charging
hose enters the air conditioner cycle together with the
refrigerant. Vacuum pump adaptor with a solenoid valve is used
to prevent this back-flow of oil from the vacuum pump. The role
of the solenoid valve is that when the current passes through
the solenoid valve, the valve closes to keep out the outside air
and allow the vacuum to build up, but when the current stops,
the valve opens to allow in air and end the vacuum.
2. Attaching this adaptor to the R12 vacuum pump currently being
used allows the pump to be used with both R134a and R12.
9Y1210003CAS0012US0
(4) Electric Gas Leak Tester
The current R12 gas leak tester has poor sensitivity for R134a
and cannot be used. Therefore, a new electric gas leak tester with
greater sensitivity has been designed and can be used with both
R134a and R12.
(Reference)
Leak tester with halide torch
• Since the reaction with chlorine within the refrigerant is used to
detect gas leaks, R134a, which contains no chlorine, cannot be
detected.
9Y1210003CAS0013US0
(5) Can Tap Valve
The can tap valve that is used to charge the refrigerant into the
air conditioning system, should be used as follows:
1. Before putting the can tap valve on the refrigerant container,
turn the handle (1) counterclockwise till the valve needle is fully
retracted.
2. Turn the plate nut (disc) (4) counterclockwise till it reaches its
highest position, then screw down the can tap valve into the
sealed tap.
3. Turn the place nut clockwise fully, and fix the center charging
hose to the valve.
4. Tighten the place nut firmly by hand.
5. Turn the handle (1) clockwise, thus making a hole in the sealed
tap.
6. To charge the refrigerant into the system, turn the handle (1)
counterclockwise. To stop charging, turn it clockwise.
9Y1210003CAS0014US0
(1) Vacuum Pump Adaptor
(2) Vacuum Pump
(3) Magnetic Valve
(4) Blind Cap (5) Air
(6) For R134a
(7) For R12
(1) Electric Gas Leak Tester
(1) Butterfly Handle
(2) Connection (3) Needle
(4) Disc
KiSC issued 05, 2012 A