BENDIX AD-4 AIR DRYER Manuale utente

SD-08-2407

Bendix®AD-4™Air Dryer

EXTENDED PURGE AD-4™AIR DRYER STANDARD AD-4™AIR DRYER

LOWER

BRACKET

DESCRIPTION

ThefunctionoftheAD-4™airdryeristocollectand remove

air system contaminants in solid, liquid and vapor form be-

fore they enter the brake system. It provides clean, dry air

to the components of the brake system which increases

thelife ofthe systemand reducesmaintenance costs.Daily

manualdraining of thereservoirs is eliminated.

TheAD-4™airdryer consistsof a desiccantcartridgeand a

die cast aluminum end cover secured to a cylindrical steel

outer shell with eight cap screws and nuts. The end cover

containsacheckvalveassembly,asafetyvalve, purgevalve

mechanism, a cast-in heater element with a replaceable

thermostatassembly and three threadedairconnections.

The three air connections are identified with embossed

numbersandlettering.Theidentificationandfunctionofeach

is as follows:

Port l.D. Function/Connection

CON 4................ ControlPort

(fromunloaderportongovernor).

SUP 11 .............. Supply Port (air in).

DEL 2 ................ Delivery Port(air out).

A cast-in heater element and replaceable thermostat with

anexternal terminalare provided.

The voltage and wattage requirements of the heater and

thermostatareshown with embossed numbers andletters

in the recess adjacent to the control port marked “CON.”

UPPER

BRACKET

LOWER

BRACKET

PURGE

EXHAUST

FIGURE 1 - AD-4™AIR DRYER MODELS

SUPPLY

PORT

THERMOSTAT

TERMINAL

SUPPLY

PORT

CONTROL

PORT

DELIVERY PORT PURGE

EXHAUST

UPPER

BRACKET

PURGE VOLUME

DESICCANT

BED

CHECK

VALVE

OIL SEPARATOR

DESICCANT

CARTRIDGE

DELIVERY

PORT

HEATER

CHECK

VALVE

PURGE

VALVE

ORIFICE

EXHAUST

PORT

SUPPLY RESERVOIR

CONTROL

GOVERNOR COMPRESSOR

OPERATION OF THE AD-4™AIR DRYER

The AD-4™air dryer alternates between two operational

modes or “cycles” during operation: the charge cycle and

the purge cycle. The following description of operation is

separatedinto these “cycles” ofoperation.

CHARGE CYCLE (refer to Figure 2)

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

supplyportof theairdryer endcover.Theflow velocityorthe

speedat whichtheair andits contaminants traveldown the

discharge line is reduced substantially as it enters the air

dryerend coverbafflesystembehind thesupply port.Asair

travelsthroughthebafflesystem,itsdirectionofflowchanges

by 180 degrees several times, reducing the temperature,

causingcontaminantstocondense and drop to the bottom

orsump of the airdryerend cover.

After exiting the end cover baffle system, the air flows into

thedesiccant cartridge. Once in thedesiccantcartridge air

first flows through an oil separator which removes water in

liquid form as well as oil, oil vapor and solid contaminants.

FIGURE 2 - AD-4™AIR DRYER CHARGE CYCLE

Air exits the oil separator and enters the desiccant drying

bed.Air flowing through the column of desiccant becomes

progressivelydryeraswatervapor adherestothe desiccant

materialin aprocessknown as“adsorption”.Thedesiccant

cartridge using the adsorption process typically removes

95%of the watervapor from thepressurizedair.

Themajority of dryairexits the desiccantcartridge through

itsintegralsinglecheckvalvetofillthepurgevolumebetween

the desiccant cartridge and outer shell. Some air will also

exitthedesiccantcartridgethroughthepurgeorificeadjacent

tothe check valve.

Dry air flows out of the purge volume through the single

check valve assembly and out the delivery port to the first

(supply)reservoir of the airsystem.

The air dryer will remain in the charge cycle until air brake

system pressure builds to the governor cutout setting.

PURGE CYCLE (refer to Figure 3)

Whenair brakesystempressure reachesthe cutoutsetting

of the governor, the compressor unloads (air compression

stopped) and the purge cycle of the air dryer begins. The

FIGURE 3 - AD-4™AIR DRYER PURGE CYCLE

CONTROL

GOVERNOR

SUPPLY RESERVOIR

PURGE VOLUME

DESICCANT

BED

OIL SEPARATOR

DESICCANT

CARTRIDGE

DELIVERY

PORT

HEATER

CHECK

VALVE

PURGE

VALVE

COMPRESSOR

CHECK

VALVE

ORIFICE

EXHAUST

PORT

lineconnecting the governorunloaderport to theAD-4™air

dryerendcovercontrolportispressurizedwhenthegovernor

unloadsthe compressor.Airpressure attheAD-4™airdryer

end cover control port is also present on the purge valve

piston.The purge pistonmoves in responseto air pressure

causing the purge valve to open to atmosphere.

Contaminants in the end cover sump are expelled

immediately when the purge valve opens. Also, air which

wasflowingthroughthedesiccantcartridgechangesdirection

and begins to flow toward the open purge valve. Oil, water

and solid contaminants collected by the oil separator are

removedby air flowingfrom the desiccantdrying bed tothe

openpurgevalve.

Theinitialpurgeanddesiccantcartridgedecompressionlasts

onlya few secondsandis evidenced byanaudible burst of

air at theAD-4™air dryer exhaust.

The actual reactivation of the desiccant drying bed begins

asdryair flowsfromthe purgevolumethrough thedesiccant

cartridge purge orifice and into the desiccant drying bed.

Pressurizedairfromthepurgevolumeexpandsafterpassing

through the purge orifice; its pressure is lowered and its

volumeincreased.Theflowof dryair throughthedryingbed

reactivates the desiccant material by removing the water

vaporadhering to it. Generally15-30 seconds arerequired

forthe entire purgevolumeof astandardAD-4™airdryerto

flowthrough the desiccant dryingbed.

The end cover single check valve assembly prevents air

pressurein the brakesystemfrom returning totheair dryer

during the purge cycle.After the 30 second purge cycle is

complete,the air dryer is readyfor the next charge cycleto

begin.

The purge valve will remain open after the purge cycle is

completeandwill not close untilairbrake system pressure

is reduced and the governor signals the compressor to

charge.

PREVENTIVE MAINTENANCE

Important: Review the warranty policy before performing

anyintrusivemaintenanceprocedures.Anextendedwarranty

maybe voidedif intrusivemaintenanceis performedduring

thisperiod.

Becausenotwo vehiclesoperateunderidenticalconditions,

maintenanceandmaintenanceintervalswillvary.Experience

is a valuable guide in determining the best maintenance

intervalfor anyone particularoperation.

FIGURE 4 - AD-4™AIR DRYER SECTIONAL VIEW

DESICCANT

BED

OIL SEPARATOR

DESICCANT

CARTRIDGE

CHECK

VALVE PURGE

ORIFICE

EXHAUST

COVER

NUT

CHECK VALVE

ASSEMBLY

END COVER

HEX HEAD

SCREW

SPECIAL

WASHER DELIVERY

PORT PURGE

VALVE EXHAUST

DIAPHRAGM

O-RING

PURGE PISTON

SPRING

SEALING RING

SUPPLY

PORT

PERFORATED PLATE

PURGE VOLUME

WASHER

Every900operating hours or 25,000milesor every three

(3)months:

1. Check for moisture in the air brake system by opening

reservoirs, drain cocks, or valves and checking for

presenceofwater. If moisture is present,thedesiccant

may require replacement; however, the following

conditions can also cause water accumulation and

shouldbe considered beforereplacingthe desiccant:

A. An outside air source has been used to charge the

system. This air did not pass through the drying bed.

B. Airusage is exceptionallyhighand not normal fora

highway vehicle. This may be due to accessory air

demandsorsome unusualairrequirementthatdoes

not allow the compressor to load and unload

(compressing and non-compressing cycle) in a

normal fashion. Check for high air system leakage.

If the vehicle vocation has changed it may be

necessaryto upgradethe compressorsize. Referto

AppendixA,TableAand thecolumnentitled Vehicle

Vocation.

C. The air dryer has been installed in a system that

has been previously used without an air dryer. This

type system will be saturated with moisture and

severalweeks ofoperationmay berequiredto dryit

out.

D. Location of the air dryer is too close to the air

compressor. Refer to LocatingAD-4™Air Dryer On

Vehicle section and AppendixA, TableA, column 2

fordischarge line length.

E. In areas where more than a 30 degree range of

temperature occurs in one day, small amounts of

water can accumulate in the air brake system due

to condensation. Under these conditions, the

presence of small amounts of moisture is normal

and should not be considered as an indication that

thedryer is notperformingproperly.

Note:Asmallamount ofoilinthesystem maybe normal

and should not, in itself, be considered a reason to

replacethe desiccant;oil staineddesiccant canfunction

adequately.

2. Check mounting bolts for tightness. Retorque to 270-

385inch pounds.

3. Perform the Operation & Leakage Tests listed in this

publication.

Every 10,800 hours or 300,000 miles or 36 months:

1. Rebuildthe air dryer includingthedesiccant cartridge.

Note:The desiccantchange intervalmayvary fromvehicle

to vehicle.Although typical desiccant cartridge life is three

years, many will perform adequately for a longer period of

time.In order to takemaximumadvantage of desiccant life

andassure that replacement occurs onlywhennecessary,

itisimportantthatOperation&LeakageTestsbeperformed.

WARNING!

This air dryer is intended to remove moisture and other

contaminants normally found in the air brake system.

Do not inject alcohol, anti-freeze, or other de-icing

substances into or upstream of the air dryer. Alcohol

is removed by the dryer, but reduces the effectiveness

of the device to dry air. Use of other substances can

damage the air dryer and may void the warranty.

OPERATION & LEAKAGE TESTS

1. Test the outlet port check valve assembly by building

the air system to governor cut-out and observing a test

airgauge installedinthe supplyreservoir.Arapid lossof

pressurecould indicate a failedoutlet port check valve.

(Note: Purgevalve will be openwhengovernor cut-out

pressure is reached. Allow 45 seconds after governor

cut-outoccurstocompletethepurgecyclebeforetesting

thecheck valve.)Coat theexhaustwith asoap solution.

Leakage should not exceed a 1" bubble in 1 second.

2. Check for excessive leakage around the purge valve.

Withthe compressorin loadedmode (compressingair),

apply a soap solution to the purge valve housing

assembly exhaust port and observe that leakage does

not exceed a 1" bubble in 1 second. If the leakage

exceedsthemaximumspecified, servicethepurgevalve

housingassembly.

3. Closeallreservoirdraincocks.Build upsystempressure

togovernorcut-outandnotethatAD-4™air dryerpurges

with an audible escape of air. “Fan” the service brakes

to reduce system air pressure to governor cut-in. Note

thatthe systemonceagain buildstofull pressureand is

followedby anAD-4™air dryerpurge.

4. Check the operation of the safety valve by pulling the

exposed stem while the compressor is loaded

(compressingair).Theremustbe anexhaustofairwhile

the stem is held and the valve should reseat when the

stem is released.

5. Check all lines and fittings leading to and from the air

dryerfor leakage andintegrity.

6. Check the operation of the end cover heater and

thermostat assembly during cold weather operation as

follows:

A. Electric Power to the Dryer

With the ignition or engine kill switch in the ON

position, check for power at the dryer’s electrical

terminal using a voltmeter or test light. On a single

terminalAD-4™air dryer’s disconnect the lead wire

at the end cover terminal post. Place the test leads

on the lead wire and a GOOD vehicle ground. On

dualterminalAD-4™airdryer’sdisconnect bothlead

wires at the end cover terminal posts. If there is no

voltageindicated,lookforablownfuse,brokenwires,

orcorrosion in the vehicle wiringharness.Check to

see if a good ground path exists.

B. ThermostatandHeaterOperation

Turn off the ignition switch and cool the end cover

assemblytobelow40degreesFahrenheit.Using an

ohmmeter, check the resistance between the

electricalterminalandthemetalendcover(seeFigure

5).(Note:Onthe dualterminal endcover,check the

resistance between the two terminals.) The

FIGURE 5 - AD-4™AIR DRYER SINGLE AND DUAL

TERMINAL THERMOSTAT ASSEMBLIES

DUAL WIRE SYSTEM

BOOT

1CONNECTIONS FOR POWER

AND INSULATED RETURN

BOOT

BOLD NUMBERS ARE ITEMS IN MAINTENANCE KITS

SINGLE WIRE SYSTEM

46117

THERMOSTAT

COVER

HEATER POST

resistanceshould be 2.0to 4.0 ohmsfor the 12volt,

60watt end coverand 4.0 -7.0 ohms forthe 24 volt,

120 watt end cover. These resistance values apply

toeither singleor dualterminalair dryerend covers.

Warm the end cover assembly to over 90 degrees

Fahrenheitandagainchecktheresistanceasabove.

The resistance should exceed 1000 ohms for both

singleand dual terminal air dryers.Ifthe resistance

values obtained are within the stated limits, the

thermostatandheaterassemblyisoperatingproperly.

If the resistance values obtained are outside the

stated limits, proceed to Step C to determine the

cause.

C. HeaterElementInspection

Withtheignitionorenginecontrolswitch“off”, remove

the thermostat cover (see Figure 5). Using an

ohmmeter, checkthe resistance betweenthe metal

endcoverandtheheaterpost(see Figure5). (Note:

Onthedual terminalend cover,checkthe resistance

between the two terminals.) For a 12 volt, 60 watt

end cover, the resistance should be 2.0 - 2.8 ohms

andfor a24 volt,120 wattend cover,4.0 -5.6ohms.

Theseresistancevaluesapplyto eithersingleordual

terminalairdryer endcovers.If theheaterresistance

value obtained is outside the stated limits, a new or

remanufacturedendcover shouldbe installed,since

the heater element cannot be serviced. Check that

agood groundpath existsbetween theair dryerend

cover casting and the vehicle chassis. Correct if

needed. If the heater resistance value obtained is

within the stated limits the thermostat should be

replaced (Kit Number 102657) or a new or

remanufacturedend coverinstalled. Note: The dual

terminalair dryercoverrequires kitnumber 103982.

D. Reassembly

Reinstallthethermostat coverasillustratedinFigure

5. Take special care to assure the rubber spacer

and the gasket are correctly installed, to assure

properoperation.

REBUILDING THE AD-4™AIR DRYER

GENERAL

If,after completing theroutine operationandleakage tests,

ithas beendetermined that oneor morecomponents ofthe

airdryer requires replacement ormaintenance, refer tothe

followinglistto find the appropriatekit(s).

When rebuilding or replacing components of the air dryer

use only genuine Bendix parts. For ease in servicing the

AD-4™air dryer desiccant cartridge assembly, it is

recommendedthattheairdryerberemovedfromthevehicle.

MAINTENANCE KITSAVAILABLE:

103817 MajorMaintenance Kit

Thiskit contains theparts necessary tocompletely

rebuild the AD-4™air dryer (desiccant cartridge

included)and includes kit 103980.

103818 AD-4™AirDryerPurge Valve MaintenanceKit

Thiskit contains the partsnecessaryto rebuild the

AD-4™airdryerend coverpurge valveonly.

103879 AD-4™Air Dryer Seal Kit

Thiskit containsthe outletport checkvalve andthe

o-ringsand seals requiredwhenremoving the end

coverassembly.Thiskit isincludedwithkits103980

and103981.

103980 EndCover MaintenanceKit

Thiskit contains the partsnecessaryto rebuild the

end cover of the AD-4™air dryer and includes kit

103818.

103981 DesiccantCartridge Replacement Kit

This kit contains the parts necessary to change

the desiccant cartridge only.

102657 ThermostatMaintenance Kit (singleterminal

models)

This kit contains the parts necessary to rebuild a

single terminal thermostat assembly in theAD-4™

airdryer.

103982 ThermostatMaintenance Kit(dual terminal

models)

This kit contains the parts necessary to rebuild a

two terminal thermostat assembly (insulated

ground).

288918 ThermostatCover ReplacementKit (single

terminalmodels)

This kit contains the necessary components for

replacingthe non-metallicthermostatcover.

104964 ThermostatCover ReplacementKit (dualterminal

models)

This kit contains the necessary components for

replacingthe non-metallicthermostatcover.

WARNING! PLEASE READ AND FOLLOW

THESE INSTRUCTIONS TO AVOID

PERSONAL INJURYOR DEATH:

When working on or around a vehicle, the following

general precautions should be observed at all times.

1. Park the vehicle on a level surface, apply the

parking brakes, and always block the wheels.

Always wear safety glasses.

2. Stop the engine and remove ignition key when

working under or around the vehicle. When

working in the engine compartment, the engine

should be shut off and the ignition key should be

removed. Where circumstances require that the

enginebe in operation, EXTREME CAUTIONshould

be used to prevent personal injury resulting from

contact with moving, rotating, leaking, heated or

electrically charged components.

FIGURE 6 - AD-4™AIR DRYER ASSEMBLY

AIR DRYER

HOUSING

THERMOSTAT

ASSEMBLY

SAFETY

VALVE

CHECK VALVE

ASSEMBLY

SCREW

EXHAUST COVER

1/2” CAP SCREW

PURGE VALVE

(8) CAP SCREW 3/8”

SEALING RING

SEALING PLATE

(4) DESICCANT CARTRIDGE

CAP SCREW

& LOCKWASHER

SEALING RING

END COVER

HEATER

VOLTAGE

SHOWN

SUPPLY PORT

CONTROL

PORT

SPRING

O-RING

PURGE PISTON

SPECIAL

WASHER

EXHAUST

DIAPHRAGM

DELIVERY

PORT

BRACKET

MOUNTING STRAP

CAP SCREW

5/16” X 4-1/2”

BRACKET

MOUNTING STRAP

CAP SCREW

5/16” X 4-1/2”

LOCKWASHER

NUT

LOCKWASHER

NUT

MOUNTING BRACKET HOOK (8) LOCK NUT

(8) SPECIAL

WASHER

DESICCANT

CARTRIDGE

SEALING RING

3. Do not attempt to install, remove, disassemble or

assemble a component until you have read and

thoroughly understand the recommended

procedures. Useonly theproper toolsand observe

all precautions pertaining to use of those tools.

4. If the work is being performed on the vehicle’s air

brake system, or any auxiliary pressurized air

systems,makecertain to draintheair pressure from

all reservoirs before beginning ANY work on the

vehicle. If the vehicle is equipped with an AD-IS™

air dryer system or a dryer reservoir module, be

sure to drain the purge reservoir.

5. Following the vehicle manufacturer’s

recommendedprocedures, deactivate theelectrical

system in a manner that safely removes all

electrical power from the vehicle.

6. Never exceed manufacturer’s recommended

pressures.

7. Never connect or disconnect a hose or line

containing pressure; it may whip. Never remove a

component or plug unless you are certain all

system pressure has been depleted.

8. Use only genuine Bendix®replacement parts,

components and kits. Replacement hardware,

tubing, hose, fittings, etc. must be of equivalent

size, type and strength as original equipment and

be designed specifically for such applications and

systems.

9. Components with stripped threads or damaged

parts should be replaced rather than repaired. Do

not attempt repairs requiring machining or welding

unless specifically stated and approved by the

vehicle and component manufacturer.

10. Prior to returning the vehicle to service, make

certainallcomponentsandsystemsarerestoredto

their proper operating condition.

11. Forvehicles with AntilockTraction Control (ATC),

the ATC function must be disabled (ATC indicator

lampshouldbeON)priortoperforminganyvehicle

maintenance where one or more wheels on a

drive axle are lifted off the ground and moving.

AD-4™AIR DRYER REMOVAL

1. Parkthevehicleonalevelsurfaceandpreventmovement

by means other than the brakes.

2. Drain all reservoirs to 0 p.s.i. (0 kPa).— Caution:

Compressor discharge line may still contain residual

pressure.

3. Identify and disconnect the three air lines from the end

coverand notethe positionofendcoverportsrelativeto

thevehicle.

4. Pullboot fromthe thermostatandheatercoverand slide

it onto the wire to expose the connection. Remove nut

and disconnect electrical wire from the terminal. Note:

Vehicleswithinsulatedground (2wire) systemwill have

two boots and two terminals to be disconnected. (See

Figures 5 & 8.)

5. Loosen the 5/16" X 4-1/2" hex bolt securing the upper

and lower mounting straps. Disengage the mounting

END

COVER

SPECIAL

WASHER

LOCK NUT

LOWER RIGHT ANGLE

BRACKET

EXTRA

LONG

CAP SCREW

bracket hook from the end cover (Refer to Figure 6.)

Note: If theAD-4™air dryer being serviced has a right

angle bracket instead of a lower mounting strap and

safety hook, proceed to step 6, otherwise proceed to

step 7.

6. Remove, retain and mark the two 3/8" end cover cap

screws, lock nuts and four special washers that retain

thelower mounting bracket to theend cover, also mark

thesetwoholes oftheend cover.(Theseboltsarelonger

than the other 6 bolts.)

7. RemovetheAD-4™airdryer fromitsmounting brackets

onthe vehicle.

DISASSEMBLY

The following disassembly and assembly procedure is

presented for reference purposes and presupposes that a

major rebuild of the AD-4™air dryer is being undertaken.

Severalreplacementpartsandmaintenancekitsareavailable

which do not require full disassembly. The instructions

providedwith thesepartsand kitsshould befollowedin lieu

ofthe instructions presented here.Refer to Figure 6during

disassembly.

Caution: While performing service on the AD-4™air

dryer, it is not recommended that a clamping device

(vise, C-clamp, etc.) be used to hold any die cast

aluminum component as damage may result. To hold

the end cover, install a pipe nipple in the supply port

and clamp the nipple into a vise.

1. Remove the remaining 3/8" lock nuts, special washers

and cap screws from the flange of the air dryer and

separatethe endcover fromthe airdryer outerhousing.

Separatethe desiccantcartridge andsealingplate from

FIGURE 7 - LOWER BRACKET INSTALLATION

the end cover. Remove and discard the three sealing

rings. One sealing ring is located in the groove on the

sealingplate andthe othertwo arein groovesin theend

cover.

2. Remove 1/4" cap screw from the bottom of the purge

valve and remove the diaphragm washer, exhaust

diaphragm and purge valve. Discard the exhaust

diaphragmandpurgevalve.Removepurgepiston.Note:

Holdpistondownwhenremovingcapscrewduetospring

tension.

3. Remove and discard the check valve assembly in the

recessat the delivery port ofthe end cover.

4. Removethesafetyvalvefromtheend cover(onlyifithas

beendeterminedthatitneedsreplacementduringservice

checks).

5. To removethe thermostatseethe appropriatesection in

thismanual (only ifithas been determinedthat it needs

replacementduring servicechecks).

6. Removepurge pistonand springfromthetopside ofthe

cover.

7. Remove o-ring from the purge piston and discard the

o-ring.

8. Removethe four 1/4"capscrews and lockwashersthat

secure the sealing plate to the desiccant cartridge.

Separatethe sealing plate fromthe desiccantcartridge

anddiscard thesealingring atthe baseofthe cartridge.

CLEANING & INSPECTION

1. Usingmineral spiritsor anequivalent solvent,clean and

thoroughly dry all metal parts.

2. Inspect the interior and exterior of all metal parts that

will be reused for severe corrosion, pitting and cracks.

Superficialcorrosionandorpittingontheexteriorportion

ofthe upper and lowerbody halves is acceptable.

3. Inspectthe boresofboththeend coverfor deepscuffing

orgouges.

4. Makecertain thatall purgevalve housingand endcover

passagesare open andfreeof obstructions.

5. Inspectthe pipe threads intheend cover. Make certain

theyare clean and freeofthread sealant.

6. Inspect the purge valve housing bore and seat for

excessivewear andscuffing.

7. Inspectthe purge valvepiston seat forexcessive wear.

8. Inspect all air line fittings for corrosion. Clean all old

threadsealant from thepipethreads.

9. All o-rings removed should be discarded and replaced

withnew o-ringsprovidedin appropriatekit(s).

Any component exhibiting a condition described in step 1

to 8 should be replaced.

ASSEMBLY

Priortoassembly,coatall o-rings,o-ringgrooves, andbores

witha generous amount ofbarium base lubricant.

Important Note: The single exception to prelubrication

is the sealing ring between the desiccant cartridge and

sealing plate. Refer to step number 8 for proper

installation of this sealing ring. Refer to Figure 6 during

assembly unless otherwise advised.

1. Placereturn springinto cavityin thecenter oftopside of

endcover.

2. Install the purge piston o-ring on the purge piston and

placethe purge piston inside thereturn spring installed

in Step 2.

3. Turnend coveroveron aflat cleansurface(making sure

purgepistonandreturnspringremaininproper position.)

Compressthereturnspringby pushingdownontheend

coverandalign squareshankofpurgepistonintomating

holein the endcover.

4. Placethediaphragmwasher,diaphragm,andpurgevalve

onto the 1/4" cap screw.

5. Install the 1/4" cap screw with parts on it into exhaust

coverand torque to60-80 inch pounds.

6. Install safety valve (if removed) and torque to 120-400

inch pounds, making sure that the exhaust hole is

pointeddownward when thedryeris installed.

7. Install thermostat (if removed). Refer to instructions

pertaining to thermostat installation under section

ThermostatAssembly.

8. Placesealing ringon bottomof desiccantcartridge. The

desiccantcartridge,sealingring andsealingplateshould

be wiped and free of lubricant prior to this assembly

procedure.Attachcartridgeto plate(smoothside ofplate

oppositecartridge)withfour1/4"socketheadcapscrews

andlockwashers.Torqueto 80-100inchpounds.

9. Install the two sealing rings in the recesses of the end

cover.

10. Install the check valve assembly into the end cover

making sure the tang on the check valve assembly fits

into the mating recess in the end cover.

11. Place desiccant cartridge and sealing plate assembly

ontoendcover.(Takingcarenottodisplacesealingrings.)

Thelargehole in the sealingplatemust line up withthe

check valve and spiral pins in the sealing plate must

entercorresponding holesinthe end cover.

12.Installthe outer sealing ring onthesealing plate. Place

theouter housingover thedesiccantcartridge (liningup

marksmadeontheouterhousingand endcover priorto

disassembly) and retain with eight 3/8" hex head bolts,

special washers, and lock nuts. Refer to Figure 8 for

torquepattern.Torque to270-385 inch pounds.Note:If

3/8" bolts require replacement, insure that the

replacement bolts are grade 5 minimum and the same

length as the original bolts. Use of inferior bolts can

compromise the integrity of the air dryer and lead to

prematurefailure.Where a lower,rightangle mounting

bracket(instead of alower mounting strap)is used; line

upthemarksmadeontheouterhousingand endcover.

Installthe six (standard) 3/8"cap screws, locknuts and

twelvespecial washers.The twolonger3/8"cap screws

will be used to secure the AD-4™air dryer to the right

anglemounting bracket.

Note: If during the Operation & Leakage Tests it was

determinedthatthethermostatwasinoperative,usethe

following procedure for repair or replacement. It is not

necessary to replace this unit each time the end cover

is rebuilt. Use thermostat maintenance kit 102657 for

singleterminalapplication. Fordualterminal application,

usekit#103982.(See Figure 5.)

THERMOSTAT DISASSEMBLY (Refer to Figures 5

and 8)

1. Remove nut (2), then lockwasher (3), plain washer (4),

nut (2) and o-rings (5). Discard o-ring and retain other

parts.

2. Remove and retain four Phillips head screws (7) and

cover(6).

3. Removeand discardgasket (10).

4. Removeand retainspacer(11).

5. Cutuninsulated thermostatwireat PointB, remove and

discardthermostatand terminal assembly (1).

6. Cleanremaining wire attachedto heater terminal.

7. Cleanthermostat “pocket” inendcover (9).

THERMOSTAT ASSEMBLY (Refer to Figure 5)

1. Cut uninsulated lead of new thermostat (1) at PointA.

2. Install thermostat in end cover pocket and position

uninsulated leads next to each other.

3. Usinga soldering heatsink,clamp uninsulatedleadsat

PointB and solder leadswithstraight rosin core solder.

Do not use acid core solder as corrosion can result.

Cleanexcess solder offend cover.

4. Installthermostat terminal (1) incover (6).

5. Install o-ring (5), washer (4), and nut (2).Torque nut to

20-30inch pounds. Then installlockwasher (3) and nut

(2)finger tightto allowfor reconnectionofelectricalwire

whenreinstalled onvehicle.

6. Installspacer(11) over thermostat(1).

7. Install gasket (7) and thermostat cover (6) and secure

thermostatcoverto end cover (9) usingscrews(7) and

lockwashers(8).

8. Torque to 20-30inch pounds.

9. Test thermostat as follows:

A. At a temperature above 90 degrees Fahrenheit,

check resistance between thermostat terminal (1)

andendcover(9). Resistanceshouldbe1,000ohms

or greater; if not, check for solder “path” short.

B. Chill entire end cover assembly to 40 degrees

Fahrenheit or below and check resistance again.

Resistanceshould be2-4 ohmsfor a12 volt,60 watt

end cover and 4-7 ohms for a 24 volt, 120 watt end

cover.

FIGURE 9 - AD-4™AIR DRYER INSTALLATION SCHEMATIC

COMPRESSOR

UNLOADER

“UNL”

PORT

AD-4™

AIR

DRYER

SUP

SUPPLY

RESERVOIR

8-10 AMP FUSE

TO IGNITION

RESERVOIR

“RES”

PORT

DEL

CON

GOVERNOR

1&9

DELIVERY

PORT

MOUNTING

BRACKET HOOK

SAFETY

VALVE

CONTROL

PORT

HEATER

VOLTS/WATTS

EMBOSSED

HERE

SUPPLY

PORT

FIGURE 8 - AD-4™AIR DRYER END COVER WITH TORQUE

PATTERN

Questo manuale è adatto per i seguenti modelli

Indice

Altri manuali BENDIX Asciugatrice

BENDIX

BENDIX AD-9 Istruzioni per il montaggio

BENDIX

BENDIX BTD 01 Guida del prodotto

BENDIX

BENDIX BTD 03 Guida del prodotto

BENDIX

BENDIX BTD 01 Manuale utente

Manuali Asciugatrice popolari di altre marche

Bosch

Bosch WTA79200GB Manuale utente

Amana

Amana W10233410A Manuale utente

Miele

Miele TWH 780 WP Manuale utente

Asko

Asko T760 Manuale utente

Alliance Laundry Systems

Alliance Laundry Systems 25 Series Manuale utente

Bosch

Bosch Logixx 10 WTB76556GB Scheda tecnica

STIEBEL ELTRON

STIEBEL ELTRON Ultronic S Manuale di istruzioni

Electrolux

Electrolux EW2H328R2 Manuale utente

Beko

Beko DS8433RX1M Manuale utente

Dawlance

Dawlance Spinner DS 6000 C Manuale utente

Electrolux

Electrolux TP5080TW Manuale utente

AEG

AEG TR838P4OB Manuale utente

Indesit

Indesit IDV 75 Manuale utente

Infiniton

Infiniton SD-DG85C Manuale utente

BOMANN

BOMANN WT 5019 Manuale utente

Alliance Laundry Systems

Alliance Laundry Systems TMB795C Manuale utente

Asko

Asko T793C Manuale utente

Kenmore

Kenmore 8041 - 5.8 cu. Ft. Capacity Electric Dryer Manuale utente