DESCRIPTION
The function of both the Bendix® AD-IS®(Integrated Solution Air Dryer) air dryer and reservoir system and the Bendix® AD-IS®PuraGuard® oil coalescing air dryer and reservoir system is to collect and remove air system contaminants in solid, liquid and aerosol form before they enter the brake system and to provide—as a module—heavy vehicles with an integrated vehicle air dryer, purge reservoir, governor and a number of the charging valve components in a module. These components have been designed as an integrated air supply system.
Both air dryer and reservoir systems provide clean, dry air to the components of the brake system which increases the life of the system and reduces maintenance costs. The necessity for daily manual draining of the reservoirs is eliminated.
The Bendix AD-IS PuraGuard oil coalescing air dryer has an identical appearance to the standard Bendix AD-IS air dryer, but contains a coalescing media at the inlet of the desiccant bed. The coalescing media provides a higher level of oil removal over the standard AD-IS air dryer. The AD-IS PuraGuard oil coalescing air dryer has all of the same functions as the standard AD-IS air dryer and is used in applications where lower oil concentration levels are required.
IMPORTANT: When servicing, note that standard AD-IS air dryers or air dryer cartridges may be serviced with PuraGuard oil coalescing air dryers or cartridges, however, PuraGuard oil coalescing air dryers or cartridges must only be serviced with like replacements.
Note: Unless otherwise stated in this manual, AD-IS air dryer and reservoir systems refers to both the standard and PuraGuard oil coalescing air dryer and reservoir systems.
The function of the pressure protection valves is to protect each reservoir from a pressure loss in the other reservoir or a pressure loss in an air accessory. Each of the pressure protection valves in the AD-IS air dryer and reservoir systems may have different pressure settings. These are factory set and must not be changed or adjusted.
The air dryer and reservoir system consists of a “spin on” desiccant cartridge secured to a base assembly. The base assembly contains a delivery check valve assembly, safety valve, heater and thermostat assembly, pressure protection valves, threaded air connections and the purge valve assembly.
| Air Connection | Function/ | QTY |
| Port ID | Connection |
| |
| | | |
| 1 | Inlet Port (air in) | 1 |
| IN |
| | |
| 21 | Delivery Port Out (to Primary Reservoir) | 1 |
| PRI |
| | |
| 22 | Delivery Port out (to Secondary Reservoir) | 1 |
| SEC |
| | |
| 24 | Auxiliary Delivery Port (air out) | 4 |
| AUX 1 |
| | |
| 23 | Auxiliary Delivery Port (air out) | 1 |
| AUX 2 |
| | |
| UNL | Unloader Control Air (D-2A™Governor) | 2 |
| | | |
| RES | Common Reservoir Pressure (D-2A™Governor) | 2 |
| | | |
| EXH | Governor Exhaust | 1 |
| | | |
TABLE 1 - PORT DESIGNATIONS
The removable purge valve assembly incorporates the purge valve mechanism and a turbocharger cut-off feature that is designed to prevent loss of engine “turbo” boost pressure during the purge cycle of the Bendix® AD-IS®air dryer and reservoir system. For ease of maintenance, all replaceable assemblies can be serviced without removal of the air dryer and reservoir system from its mounting on the vehicle. Refer to Preventive Maintenance section.
BENDIX AD-IS AIR DRYER AND RESERVOIR SYSTEM OPERATION: GENERAL
(Refer to Figure 2.)
The Bendix AD-IS air dryer and reservoir systems are designed to receive compressed air from the vehicle air compressor, clean and dry the air, deliver air to the vehicle’s primary reservoir, secondary reservoir and accessories, and control the compressor/dryer charge cycle.
The AD-IS air dryer and reservoir system alternates between two modes or “cycles” during operation: the Charge Cycle and the Purge Cycle. The following describes these “cycles” of operation.
