Bendix Commercial Vehicle Systems AD-IS EVERFLOW ASSEMBLY - Manual (Page 2)

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Additionally, the AD-IS ® EverFlow ™ assembly controls the
compressor/dryer charge cycle.
AD-IS ® EVERFLOW ™ AIR DRYER OPERATION:
GENERAL
The AD-IS ® EverFlow ™ assembly alternates between the
dryers each time the brake system charges. During high
air demand, the dryers alternate every 30 seconds to allow
drying of the added volume of air. A pressure protection
valve is needed after the dryers to maintain at least 70
PSIG at the dryers during high air demand. An electronic
module monitors the air brake system and determines
the amount of demand. The AD-IS
® EverFlow ™ assembly
requires a signal from the delivery port of the governor into
the GOV port of the EverFlow
™ electronic module. The
AD-IS ® EverFlow ™ Assembly also needs a supply air line
from the secondary tank to the electronic module RES port.
This line must be 3/8 inch tubing or larger.
The AD-IS ® EverFlow ™ assembly is primarily designed
to dry air on systems used for bulk unload and central
tire infl ation. The system operates best when a pressure
protection valve is installed between the AD-IS
® EverFlow ™
assembly and the source of the high volume air. Refer to
the system schematics, Figure 2. This pressure protection
valve should have a minimum pressure of 70 PSIG.
Delivery pressure in excess of 175 PSIG can cause
the purge valve to cycle rapidly between load and
purge mode.
NORMAL BRAKE CYCLE (Refer to Figure 2)
When the compressor is charging (compressing air) air
fl ows through the compressor discharge line to the inlet
(1 IN) port of one of the air dryers. The compressed air
includes contaminates such as oil, oil vapor, water and
water vapor. The air then fl ows into the desiccant cartridge,
where it fl ows through a liquid separator which collects
liquids and other contaminants.
Air
Connection Function/Connection QTY
Port ID
1
IN
21
PRI
22
SEC
24
AUX
1
23
AUX
2
UNL Unloader Control Air (D-2A ™ Governor) 2
RES Common Reservoir Pressure
(D-2A ™ Governor) 2
TABLE 1 - AD-IS ® AIR DRYER PORT DESIGNATIONS
Inlet Port (air in). 1
Delivery Port out (to Primary reservoir) 1
Delivery Port out (to Secondary reservoir) 1
Auxiliary Delivery Port (air out). 4
Auxiliary Delivery Port (air out). 1
DESCRIPTION
The function of the AD-IS ® EverFlow ™ assembly is to
provide heavy vehicles that use large amounts of air with
a dryer system that facilitates continuous fl ow drying. This
assembly provides, in a single package, all the components
necessary to operate two dryers. The assembly determines
if high air demand is needed and continuously switches
between dryers every 30 seconds until the high air demand
ceases. When high air demand is not needed, the assembly
uses the dryers as if in a normal braking system. Each
dryer cycles as the air brake system requires. This feature
prevents wasted air and unnecessary cycles. The assembly
uses an electronic module that determines air demand and
sequences the dryers for maximum effi ciency.
The AD-IS ® air dryer collects and removes air system
contaminants in solid, liquid and vapor form before they
enter the brake system. It provides clean, dry air to the
components of the brake system which increases the life of
the system and reduces maintenance costs. Daily manual
draining of the reservoirs is eliminated, but still may be
mandated by law.
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 may have different
pressure settings, but these are factory set and must not
be changed or adjusted.
The air dryer 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.
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 AD-IS
® air dryer.
For ease of maintenance, all replaceable assemblies
can be serviced without removal of the air dryer from its
mounting on the vehicle. Refer to Preventive Maintenance
section.
These units will not operate properly with a Holset type
compressor. For discharge line unloaded compressors
a three way valve must be installed upstream of the air
dryer. Contact Bendix Commercial Vehicle Systems for
additional information.
AD-IS ® EVERFLOW ™ ASSEMBLY OPERATION
GENERAL (Refer to Figure 2)
The AD-IS ® EverFlow ™ assembly is designed to receive
compressed air from the vehicle air compressor. It then
cleans and dries the air before delivering it to the vehicle’s
primary reservoir, secondary reservoir and accessories.