General

FEEDBACK

LINE

DISCHARGE LINE	SUPPLY
	RES.

HOLSET COMPRESSOR

FIGURE A

HOLSET TYPE E & QE COMPRESSORS - NO AIR DRYER

STANDARD AD-IP™AIR

SPECIAL DISCHARGE

PORT FTG. W/

FEEDBACK LINE

CONNECTIONCHECK VALVE

HOLSET

COMPRESSOR

DRYER

SUPPLY

RES.

FEEDBACK LINE

DISCHARGE

PORT

LOWER

MTG. BRKT.

(PARTIAL) FEEDBACK LINE

SPECIAL DISCHARGE

PORT FTG. W/

FEEDBACK LINE

CONNECTION END COVER

BOTTOM VIEW

FIGURE 2 - AD-IP™DI DROP IN AIR DRYER FOR HOLSET

COMPRESSORS

AD-IP™DI “DROP IN” AIR DRYER MODEL

In addition to the standard AD-IP™air dryer, the Bendix® AD-IP™DI (Drop In) air dryer is also offered. It is a specialized version designed especially for air systems that use either the Holset (Cummins) Type E or QE air compressor. These Holset compressors utilize an unusual unloading system that requires that air pressure remain in the discharge line during the entire unloaded cycle of the compressor. To accomplish this, Holset compressors rely on air “feedback” from the supply reservoir as shown in Figure 3B. When an air dryer is installed the direct “feedback” from the supply reservoir is interrupted and an alternate source for “feedback” pressure must be provided. A standard AD-IP™air dryer can be installed, however a separate “feedback” line with a single check must be installed as shown in Figure 3C.

The AD-IP™DI drop in air dryer model incorporates the feedback line and single check as an integral part of the dryer and eliminates the need for these components as shown in Figures 2 & 3C.

W/CHECK VALVE

FIGURE B

STANDARD AD-IP™AIR DRYER AND

HOLSET TYPE E & QE COMPRESSORS

HOLSET

COMPRESSOR

	AD-IP™DI DROP IN AIR	SUPPLY
	DRYER W/FEEDBACK
		RES.
	LINE & CHECK VALVE

FIGURE C

AD-IP™DI DROP IN AIR DRYER AND

HOLSET TYPE E & QE COMPRESSORS

FIGURE 3 - AD-IP™AIR DRYER AND HOLSET TYPE E & QE

COMPRESSORS

OPERATION

The AD-IP™air dryer alternates between two operational modes or “cycles” during operation: the Charge Cycle and the Purge Cycle. The following description of operation is separated into these “cycles” of operation.

CHARGE CYCLE (refer to Figure 4)

When the compressor is loaded (compressing air) compressed air, along with oil, oil vapor, water and water vapor flows through the compressor discharge line to the supply port of the air dryer body.

As air travels through the end cover assembly, its direction of flow changes several times, reducing the temperature, causing contaminants to condense and drop to the bottom or sump of the air dryer end cover.

After exiting the end cover, the air flows into the desiccant cartridge. Once in the desiccant cartridge air first flows through an oil separator located between the outer and inner shells of the cartridge. The separator removes water in liquid form as well as liquid oil and solid contaminants.