Bosch ACS 653-P - Plumbing and Mechanical System Operation

ACS 653, ACS 663 Service Manual
SP00D00624 2021-04-08 Robert Bosch GmbH
84
Plumbing and Mechanical

The plumbing and mechanical system
is controlled by electrical impulses from
the electrical system. There are four main
components to the plumbing system:
• Compressor
• Vacuum Pump
• Internal Storage Vessel (ISV)
• Main Manifold Assembly
Along with these components are several
ancillary components:
• Cooling Fan
• Injection Manifold Assembly
• Flush Manifold Assembly
• Oil Drain Bottle
• High- and Low-Side Gauges
• High- (red) and Low-Side (blue) Service
Hoses
All components are interconnected with various
lengths and diameters of flexible tubing or
copper tubing. The copper tubing connects the
compressor discharge port to the main manifold
assembly. All lines connected to the compressor
are high-pressure lines.
Every time the circuit under pressure is
opens or one component (hoses, compressor,
gauges) is replaced, perform a pressure leak
test with external leak detector.

When replacing the compressor, heed all
warnings, cautions, and any other related safety
information. For compressor specications, see
Unit Specications chapter of this manual.

The vacuum pump is used in this unit for the
recovery and vacuum processes. For vacuum
pump specications, see Unit Specications
chapter of this manual.

The ISV stores the refrigerant from the
vehicle A/C system and from the external
refrigerant source tank. Sensors, solenoids,
and transducers on the ISV include:
• Air Purge (S1)
• Tank liquid (S22)
• ISV Pressure (TP) transducer
• ISV Temperature (TT) sensor

The main manifold assembly consists of
solenoids:
• Oil Drain (S3)
• Low-Side Inlet (S4)
• High-Side Inlet (S5)
• High-Side Charge (S6)
• Low-Side Charge (S7)
• Recycle (S8)
• Vacuum (S9)
• Recover (S11)
• Deep Recover (S12)
• Oil Return (S13)
• Identifier (S17). Is used on ACS 663-RI
unit only
Also included are transducers:
• Low Side Pressure (LSP) transducer
• Accumulator Pressure (AP) transducer
The main manifold assembly permits e󰀩cient,
reliable operation of the unit. The oil separator
and heat exchanger are a single unit.
That and the lter/dryer are attached below
the manifold. This main manifold assembly is
not interchangeable with any other manifold
assembly.
Repair or replacement of the manifold should
be performed under clean conditions so
particulates do not enter the assembly from
any open ports. Particulates can clog the small
chambers and cause solenoid and check valve
malfunctions, as well as contaminate a vehicle
air conditioning system.