Service manual

ManualsBrandsBENDIX ManualsDryerAD-1 AIR DRYER

G. Air compressor

discharge and/or air

dryer inlet temperature

too high.

AD-9

™

AIR DRYER TROUBLESHOOTING CHART

SYMPTOMS CAUSE

REMEDY

Purge Cycle Time - During normal vehicle

operation, the air compressor must remain

unloaded for a minimum of 20 seconds for

the standard AD-9

™

air dryer or 30 seconds

for the Extended Purge Model. These

minimum purge times are required to ensure

complete regeneration of the desiccant material.

If the purge time is consistently less than the

minimum, an accessory by-pass system must

be installed. Consult your local authorized Bendix

parts outlet or sales representative for additional

information.

European Air Brake Systems - Brake systems

that incorporate compressors without integral

unloading mechanisms and/or utilize a

compressor discharge line unloader valve have

special air dryer installation requirements.

Consult your local authorized Bendix parts outlet

or sales representative for additional information.

Air Compressor Size - Although the AD-9

™

air

dryer can be used in conjunction with larger

compressors, it was designed primarily for units

rated for up to 17 CFM. It is recommended that

when using the AD-9

™

air dryer with a

compressor which has a rated displacement

exceeding 17 CFM that an authorized Bendix

parts outlet or Bendix marketing representative

be contacted for assistance.

G. Restricted discharge line. See Appendix A,

Table A, column 1 & 2 for recommended sizes. If

discharge line is restricted or more than 1/16"

carbon build up is found, replace the discharge

line. Replace as necessary.

Discharge Line Freeze-Up. The discharge line

must maintain a constant slope down from the

compressor to the air dryer inlet fitting to avoid low

points where ice may form and block the flow. If,

instead, ice blockages occur at the air dryer inlet,

insulation may be added here, or if the inlet fitting is

a typical 90 degree fitting, it may be changed to a

straight or 45 degree fitting. For more information on

how to help prevent discharge line freeze-ups, see

Bendix Bulletins TCH-08-21 and TCH-08-22. Shorter

discharge line lengths or insulation may be required

in cold climates.

Insufficient coolant flow through compressor.

Inspect coolant line. Replace as necessary (I.D. is

1/2" min.). Inspect the coolant lines for kinks and

restrictions and fittings for restrictions. Replace as

necessary. Verify coolant lines go from engine block

to compressor and back to the water pump. Repair

as necessary.