Bendix Commercial Vehicle Systems AD-IS AIR DRYER AND RESERVOIR SYSTM - Manual (Page 9)

9
BRAKING SYSTEM PROTECTION
The Bendix ® AD-IS ® air dryer allows the system to maintain
one brake circuit up to about 100 psi even after a pressure
loss in the other brake circuit. This allows a vehicle to
be moved (in an emergency), but with reduced braking
capacity. Compare this to a conventional system, where a
loss of pressure in one service tank leaves the vehicle with
a limited number of reduced braking capacity applications
before the parking brakes automatically apply and stay on.
See Bendix publication BW5057 "Air Brake Handbook."
ROADSIDE INSPECTION
In the event of a roadside inspection the system behavior
will be as follows: When the system is charged to governor
cut-out and then one reservoir drain valve is opened,
initially both reservoir gauges will fall; however, the Bendix
AD-IS air dryer primary and secondary pressure protection
valves will close at pressures above 70 psi, protecting the
remaining brake circuit from further loss of pressure.
TEMPORARY AIR DRYER AND RESERVOIR
SYSTEM BYPASS
To temporarily bypass the air dryer, follow these procedures:
Adhere to the General Safety Guidelines outlined
elsewhere in this document.
Make sure that all residual pressure has been released and
the air dryer purge reservoir has been drained to 0 psi,
then remove the air supply line from the compressor to the
inlet port (1/IN). Remove the safety valve from the Bendix
AD-IS air dryer (see Figure 1 for location). Note that a short
puff of trapped air may vent from the safety valve port when
removing the valve. Install a T-fitting into the port. Using
any adapters necessary, reinstall the safety valve in one of
the branches of the T-fitting. Using any adapters necessary,
install the air supply line into the remaining T-fitting port.
After testing the T-fitting for any air leakage—by using a
soap solution after charging to system cut-out pressure (a
1” bubble in 10 seconds is acceptable)—the vehicle may
be returned to temporary service.
Note: This is a temporary bypass of the air dryer. Full
repair of the unit must be carried out at the earliest
opportunity.
With the air dryer removed from the system, contaminants
will be entering the air brake system: reservoirs will need to
be manually drained daily until the repairs are completed.
At the end of each working day, park the vehicle and slowly
drain pressure through the drain valves—leave open to
the atmosphere—for several hours, if possible. When
repairs are carried out, be sure to check that all reservoirs
(including the air dryer purge reservoir) are emptied of all
contaminants.
If, after bypassing the air dryer and reservoir system, the
system pressure still does not build, use the following
procedure to remove, clean, and reinstall the delivery
check valve.
Maintenance Kits
Kit Description Piece No.
Delivery Check Valve Replacement Kit 5004052
Desiccant Cartridge Replacement Kit (Standard) 5008414
Desiccant Cartridge Replacement Kit - Bendix ® AD-IS ®
PuraGuard ® air dryer (can be used to replace the standard
cartridge)
5008414PG
Drain Valve 5004961N
Governor and Check Valve Replacement Kit 5004049
Governor Gasket 5007834
Heater & Thermostat Replacement (12 volt) 109495
Heater & Thermostat Replacement (24 volt) 109496
Bendix ® PuraGuard ® Oil Coalescing Desiccant Cartridge
Service New Kit
K020366
Mounting Bolt Kit 5009233
Protective Boots (for pressure protection valves) 5005163
Safety Valve 800350
Splash Shield Kit (includes bracket and cover) K052469
Splash Shield Cover 5005266N
Silencer Kit K021189
Wiring Harness & Splice Kit 109871N
Purge Valve Assembly Type Configuration
Service Kit
Pc. No.
Purge Valve Assembly for
climate conditions above
-40°C (-40°F)
Bendix ® AD-IS ® Air Dryer K022105
AD-IS ® EverFlow ®
Module
K031560
AD-IS ® Discharge Line
Unloader
K031562
Arctic Purge Valve Assembly
for climate conditions of
-40°C to -50°C
(-40°F to -58°F)
AD-IS ® Air Dryer K031559
AD-IS ® EverFlow ®
Module
K031561
AD-IS ® Discharge Line
Unloader
K031563