Bosch ACS 653 Repair Instruction page 90

Plumbing and Mechanical
Replacement ISV Assembly
WARNING: Disconnect the unit from
the power source before beginning
service work. Incorrect use or
connections can cause electrical
shock.
WARNING: Wear safety goggles
when working with refrigerants.
Refrigerants can cause eye injury.
WARNING: Use extreme caution
w h e n d i s c o n n e c t i n g h o s e s .
Pressurized refrigerant may be
present in hoses. Point hoses away
from you and anyone nearby.
Instructions
These instructions outline the steps to replace
the ISV assembly.
Removing ISV Assembly
1. Depressurize the unit (select "AC unit
emptying" function in the service menu).
2. Disconnect unit from the power source.
3. Remove the front plastic cover and service
hoses.
4. Disconnect the liquid hose and vapor hose
from the tank.
5. D i s c o n n e c t t h e w i r e s f r o m t h e a i r
purge solenoid, tank liquid solenoid,
tank temperature sensor, and pressure
transducer.
6. Remove the two bolts securing the tank to
the scale.
7. Remove the tank from the scale.
SP00D00624 2021-04-08
ACS 653, ACS 663 Service Manual
Installing Replacement ISV Assembly
1. Place the tank on the scale.
2. Secure the tank to the scale with two bolts.
3. Reconnect liquid and vapor hoses to tank.
4. Reconnect tank temperature sensor, air
purge solenoid, tank liquid solenoid and
pressure transducer wires.
5. Connect the unit to the power source.
6. Attach the outside high- (red) and low-side
(blue) service hoses. Tighten at 7.9 Nm
torque.
7. Perform tank fill (refer to "Tank Fill" in the
Maintenance section).
NOTE: Every time the ISV is replaced, during
the tank fill, perform a test with external leak
detector.
8. Clear service hoses and remove them.
9. Reinstall the front plastic cover.
10. Attach the outside high- (red) and low-side
(blue) service hoses. Tighten at 7.9 Nm
torque.
90
Robert Bosch GmbH