background image

2-1

IInnssttaallllaattiioonn

aanndd 

 

O

Oppeerraattiioonn

2

Use information in this chapter to:
• Prepare 

D

Duuaall 

 

33441122

for initial use, 

• Recover vehicle refrigerant,
• Create a vacuum before recharging, and
• Recharge with recycled refrigerant.

Connecting Service Hoses to 

D

Duuaall 

 

33441122

Use the following procedure to connect service hoses to 

D

Duuaall

33441122

.  Refer to 

Figure 2-1

.

• Do not use 

D

Duuaall 

 

33441122

or leak detector equipment if

R-12 substitutes are suspected.  R-12 refrigerant

substitutes may be flammable.

• Read, understand and follow 

S

Saaffeettyy 

 

IInnffoorrm

maattiioonn

in

the front of this manual.

• Refer to 

P

Paaggee 

 

11--44

3

3

3

3

Confirm refrigerant type in vehicle,  and use
appropriate connections on unit.  

3

3

3

3

Always lubricate rubber gaskets and seals at hose
connections with fresh refrigerant oil before connecting.  

3

3

3

3

Tighten hose connections finger tight.  Use electronic
leak detector to insure connections are leak free.

1. Connect an anti-blowback valve, two found in unit

accessories, to end of each yellow service hose with
hand valve.

2. Attach end of yellow hoses without hand valve to center

port of manifold gauge assemblies.

3. Attach end of yellow hoses with hand valve and anti-

blowback valve to “Recycle” port on side panel. 

4. Attach end of blue hoses, without hand valve (R-12), to

low side (left) port of manifold gauge assembly.

5. Attach end of red hoses, without hand valve (R-12), to

high side (right) port of manifold gauge assembly.

6. 134a refrigerant only – connect high (red) and low (blue)

couplers to their respective hoses. Rotate coupler knobs
fully CCW (closed).

Summary of Contents for Dual 3412

Page 1: ...and Installing Recovery Tank 2 3 Operation 2 6 Preliminary Checks 2 7 Connecting Service Hoses To Vehicle 2 9 Recover Recycle Refrigerant From Vehicle 2 10 Purging Non condensable Gas 2 11 Evacuating A C System 2 12 Charging A C System 2 13 Displaying Refrigerant Amount 2 14 Tank Full Empty 2 14 Removing Recovery Tank 2 14 Evacuating Service Hoses 2 14 Adding Refrigerant To Dual 3412 2 15 M Ma ai ...

Page 2: ...ii T Ta ab bl le e o of f C Co on nt te en nt ts s ...

Page 3: ...essories 1 8 Figure 1 4 R 134a Accessories 1 9 I In ns st ta al ll la at ti io on n a an nd d O Op pe er ra at ti io on n Figure 2 1 Service Hoses and Gauge Sets 2 2 Figure 2 2 Recovery Tank and Temperature Probe 2 6 Figure 2 3 Service Hose Connections to Vehicle 2 9 M Ma ai in nt te en na an nc ce e Figure 3 1 Moisture Indicator Chart 3 2 Figure 3 2 Master Filter 3 6 Figure 3 3 Pump 3 7 iii ...

Page 4: ...trademark of Snap on Tools Company D Du ua al l 3 34 41 12 2 is a registered trademark of S Sn na ap p o on n Tools Co C Co op py yr ri ig gh ht t I In nf fo or rm ma at ti io on n D Du ua al l 3 34 41 12 2 User s Manual 1997 1998 S Sn na ap p o on n Incorporated The information specifications and illustrations in this manual are based on the latest information available at the time of printing S ...

Page 5: ...ens valves References in text to opening and closing service hose valves assume Valve is open with lever parallel to hose and Valve is closed with lever perpendicular to hose References in text to opening and closing 134a couplers assume Counterclockwise closes valves and Clockwise opens valves Check Note A check note provides additional information about the subject in the preceding paragraph Exa...

Page 6: ...cates an imminently hazardous situation which if not avoided will result in death or serious injury to the operator or to bystanders Indicates a potential hazard which if not avoided could result in death or serious injury to the operator or to bystanders Indicates a potential hazard which if not avoided may result in minor or moderate injury to the operator or to bystanders Some safety messages c...

Page 7: ...the process of removing refrigerant from a system filtering drying and storing it in the recovery tank 3 3 3 3 Recycle is the only process that removes refrigerant There is not a separate recovery process 3 3 3 3 Dual 3412 is a single pass unit This means refrigerant is filtered and dried before reaching the recovery tank Once in the recovery tank it is ready for reuse after manual purging if nece...

Page 8: ...viii U Us si in ng g t th hi is s M Ma an nu ua al l ...

Page 9: ...sponsibility to be knowledgeable of the system that is to be tested It is essential to use proper service methods and test procedures and to perform tests in an appropriate and acceptable manner that does not endanger your safety the safety of others in the work area or the vehicle or equipment being tested It is assumed that the operator has a thorough understanding of vehicle air conditioning sy...

Page 10: ...nces of not avoiding the hazard An icon when present gives a graphical description of the potential hazard IMPORTANT SAFETY INSTRUCTIONS Risk of suffocation Vehicle exhaust gases contain carbon monoxide Refrigerant gas can displace air in work area Use D Du ua al l 3 34 41 12 2 in locations with mechanical ventilation providing at least four air changes per hour Suffocation will cause injury Power...

Page 11: ...25 F 52 C Explosion can cause injury Risk of fire Do not use this equipment in the vicinity of spilled or opened containers of gasoline Do not use D Du ua al l 3 34 41 12 2 or leak detector equipment if R 12 substitutes are suspected R 12 refrigerant substitutes may be flammable Fire can cause injury Risk of poison Avoid breathing air conditioning refrigerant and lubricant vapor or mist Do not all...

Page 12: ...er places in the engine compartment Contact with electrical connections and hot or moving parts can cause injury Service hoses can not withstand high temperatures or severe mechanical stress Keep the service hoses away from moving or hot engine parts Service hoses can split or burst causing injury Risk of explosion if improper tank is used Do not use any tank with this equipment other than part nu...

Page 13: ...l may result in injury Hose couplings are not self closing Always close the valves on the gauge set before disconnecting a hose Loosened hose couplings can leak refrigerant to the atmosphere Misdiagnosis may lead to incorrect or improper repair and or adjustment Do not rely on erratic questionable or obviously erroneous test information or results If test information or results are erratic questio...

Page 14: ...VI S Sa af fe et ty y I In nf fo or rm ma at ti io on n ...

Page 15: ...fter manual purging if necessary See Chapter 2 Recovering Refrigerant From Vehicle There is no need to perform a separate recycle function Recover evacuate and recharge functions are performed manually This manual applies to the following D Du ua al l 3 34 41 12 2 model Name Model Refrigerant Type Voltage Dual 3412 EEAC112B R 12 R 134a 120 VAC References in text to D Du ua al l 3 34 41 12 2 apply ...

Page 16: ...h products Regulatory action is necessary because when the chlorine content in R 12 is exposed to the atmosphere It depletes the protective ozone layer in the atmosphere It has relatively high global warming potential and Its long atmospheric lifetime is approximately 120 years R 134a has been developed for new vehicle production but does not replace or directly substitute for R 12 in existing veh...

Page 17: ...fer to C Ch ha ap pt te er r 3 3 C Ch ha an ng gi in ng g t th he e M Ma as st te er r F Fi il lt te er r Prevent refrigerant from contacting the skin Read understand and follow S Sa af fe et ty y I In nf fo or rm ma at ti io on n in the front of this manual Use D Du ua al l 3 34 41 12 2 in locations with mechanical ventilation providing at least four air changes per hour Avoid breathing air condi...

Page 18: ...ion Some of these products are OZ 12 Refrigerant 176 Arctic Chill R 176 and GHG Refrigerant 12 Some vehicles using OZ 12 can be identified by a label that may be placed in the engine compartment but many cannot be identified Studies are currently being conducted to develop a procedure to identify the type of refrigerant in a refrigeration system State agencies and the Environmental Protection Agen...

Page 19: ...sures Right hand valve opens and closes the high side service hose passage to D Du ua al l 3 34 41 12 2 Left hand valve opens and closes the low side service hose passage to D Du ua al l 3 34 41 12 2 Control Panel Houses display screen and control buttons Mode Button Toggles LCD display between gross weight of recovery tank and tare weight which zeroes the display for indication of charged or recy...

Page 20: ...hen overload indicator lights Temperature Display Shows recovery tank temperature Use this along with pressure temperature chart on front panel when purging non condensable gas For additional information refer to Chapter 2 Purging Non condensable Gas Pressure Gauge Shows recovery tank pressure Use this along with pressure temperature chart on front panel when purging non condensable gas For additi...

Page 21: ...refer to Chapter 3 Changing the Master Filter E Scale Electronically measures the amount of refrigerant dispensed recycled and remaining in the recovery tank Oil Separator Internal Removes oil and other contaminants from the refrigerant being recycled F Service Ports On Sides The yellow service hose from the gauge set attaches to the service port G Oil Drain Valve Used to drain recovered oil from ...

Page 22: ...eft hand valve opens and closes the low side service hose passage to D Du ua al l 3 34 41 12 2 B Service Hoses Red blue and yellow hoses for connecting gauge set to vehicle and D Du ua al l 3 34 41 12 2 For additional information refer to Chapter 2 Connecting Service Hoses to D Du ua al l 3 34 41 12 2 and Chapter 2 Connecting Service Hoses to Vehicle C GM Adaptor Connects to high side service port...

Page 23: ...D Du ua al l 3 34 41 12 2 Left hand valve opens and closes the low side service hose passage to D Du ua al l 3 34 41 12 2 B Service Hoses Red blue and yellow hoses for connecting gauge set to vehicle and D Du ua al l 3 34 41 12 2 For additional information refer to Chapter 2 Connecting Service Hoses to D Du ua al l 3 34 41 12 2 and Chapter 2 Connecting Service Hoses to Vehicle C Shut off Adaptors ...

Page 24: ...nds Dimensions Depth 26 Height 48 Width 21 Operating Operating Temperature Range 50 120 F ambient Maximum Operating Pressure 300 psig Pressure Range 30 inHg 300 psi Refrigerant Charge Amount 0 25 pounds Recovery Amount 0 25 pounds Recovery Rate 1 pound minute maximum Recycled Refrigerant Tank 30 lb with purge port for each tank ...

Page 25: ...1 11 I In nt tr ro od du uc ct ti io on n Storage Temperature 4 158 F Relative Humidity Up to 80 non condensing Capacities Recovery Up to 25 lbs total ...

Page 26: ...1 12 I In nt tr ro od du uc ct ti io on n ...

Page 27: ...frigerant type in vehicle and use appropriate connections on unit 3 3 3 3 Always lubricate rubber gaskets and seals at hose connections with fresh refrigerant oil before connecting 3 3 3 3 Tighten hose connections finger tight Use electronic leak detector to insure connections are leak free 1 Connect an anti blowback valve two found in unit accessories to end of each yellow service hose with hand ...

Page 28: ... Hose Coupler with valve B Blue Hose C High Side Red Hose Coupler with valve D Red Hose E Yellow Hose F Hand Valve G Service Port Fitting Q Anti Blowback Valve R 12 H Low Side Blue Hose Fitting I Blue Hose J Hand Valve K High Side Red Hose Fitting L Red Hose M Hand Valve N Yellow Hose O Hand Valve P Service Port Fitting Q Anti Blowback Valve ...

Page 29: ...of 25 inHg vacuum when evacuation is complete If there is not 25 inHg vacuum check connections and repeat the procedure Tank Preparation Follow this procedure to install new recovery tanks in D Du ua al l 3 34 41 12 2 New tanks are charged with dry air which must be vented before using tank This procedure may be used for both tanks at the same time Wear safety goggles user and bystander Cover blue...

Page 30: ...n red service hose 12 Open the following Yellow service hose hand valve Blue service hose hand valve or coupler CW High side manifold hand valve and Low side manifold hand valve 13 Turn both compressor switches OFF 14 Turn both vacuum recycle valves OFF 15 Connect power cord to wall outlet having correct voltage for unit For additional information refer to Chapter 2 Specifications UNIT ON indicato...

Page 31: ...Turn compressor switch ON COMPRESSOR ON indicator illuminates and compressor activates 28 Turn vacuum recycle valve to RECYCLE Refrigerant flows from virgin tank through D Du ua al l 3 34 41 12 2 and into prepared recovery tank 3 3 3 3 Press mode button until Tare Weight is displayed Monitor weight on LCD display until desired amount of virgin refrigerant has been transferred Refer to Tank Full Em...

Page 32: ...anger of explosion and potential for personal injury Inaccurate refrigerant amount may display if the correct tank is not used Operation This section contains Procedures for connecting service hoses to the vehicle and Procedures to Recycle vehicle refrigerant Create a vacuum in the A C system before recharging and Recharge the A C system with recycled refrigerant After performing all installation ...

Page 33: ...al to recover If recovery time is too short or if vehicle components are cold this parasitic refrigerant can expand during a vacuum hold test reducing the vacuum in vehicle A C system This could be interpreted as a leak yet none exists Allow Adequate Evacuation Time Evacuate the vehicle system for a minimum of 30 minutes This helps ensure vehicle A C system is free of non condensable gas mostly ai...

Page 34: ...3 34 41 12 2 outside of the following limits Warmer than 49 C 120 F Colder than 10 C 50 F and or Relative humidity greater than 80 Stabilize D Du ua al l 3 34 41 12 2 to a moderate temperature and inspect for abnormalities Contact your S Sn na ap p o on n S Su un n representative before operating if unsure of condition Operating D Du ua al l 3 34 41 12 2 with the following conditions may reduce it...

Page 35: ...connect the service hoses to the vehicle 1 Connect red high side hose with service fitting adaptor if applicable from manifold gauge set to high side service port on vehicle 2 Connect blue low side hose with service fitting adaptor if applicable from manifold gauge set to low side service port on vehicle 3 3 3 3 If the vehicle has more than one low side service port use the service port closest to...

Page 36: ...ivates 5 Turn vacuum recycle valve to RECYCLE Refrigerant flows from vehicle through D Du ua al l 3 34 41 12 2 and into recovery tank As refrigerant is recovered the low side manifold gauge shows increasing vacuum Continue recovering until low side manifold gauge indicates 15 inHg 6 Close High side manifold hand valve and Low side manifold hand valve 7 Turn vacuum recycle valve to OFF 8 Turn compr...

Page 37: ... is amount to add back into vehicle system when recharging 3 3 3 3 Discard refrigerant oil in accordance with laws in your area Purging Non condensable Gas 3 3 3 3 Be sure to purge non condensable gases immediately after each recovery and before each charge 1 Using the pressure temperature chart located on the front panel of the unit find the temperature that is the same as the reading on the temp...

Page 38: ...recycle valve to VACUUM Low side manifold gauge shows vacuum increasing 3 3 3 3 Follow manufacturer recommendations for evacuation time usually at least 30 minutes 4 Close manifold hand valves when desired vacuum and duration have been reached 5 Turn Vacuum Recycle valve OFF 6 Turn compressor switch OFF COMPRESSOR ON indicator goes out and compressor stops running 7 Monitor low side pressure for 5...

Page 39: ...tops 3 3 3 3 If desired charge amount cannot be reached Close high and low side manifold hand valves 3 3 3 3 Never run A C system with high side manifold valve open Run A C system Open low side manifold hand valve Monitor tank weight and close hand valve when desired charge amount is reached 8 Close blue liquid recovery tank hand valve 9 Monitor high and low side system pressures Refer to manufact...

Page 40: ... The unit may only be used to evacuate and charge an A C system when recovery tank is full 3 3 3 3 The unit may be used to recycle or evacuate an A C system when recovery tank is empty 3 3 3 3 Tank Empty is displayed when the Gross weight of the recovery tank is approximately less than 19 lbs 3 3 3 3 Tank Full is displayed when the Gross weight of the recovery tank is 40 lbs Removing Recovery Tank...

Page 41: ...ure may not be completed 1 Refer to Preparing and Installing Recovery Tank in this chapter 2 Open red vapor valve on recovery tank 3 Connect blue service hose from manifold gauge assembly to tank of virgin refrigerant 3 3 3 3 For R134a install supplied tank adapter between tank valve and blue hose Virgin tank should be upright valve up 4 Open the Virgin tank valve Yellow service hose hand valve Bl...

Page 42: ...rgin tank hand valve 8 Allow recycler to run until 15 Hg vacuum is reached Then close blue service hose valve 9 Turn vacuum recycle valve OFF 10 Turn compressor switch OFF 3 3 3 3 Compare recovery tank pressure temperature relationship with the chart and bleed off any non condensables air by pressing PURGE button Refer to Purging Non condensable Gas in this chapter ...

Page 43: ... the recovery tank during unit operation pAlways evacuate service hoses before disconnecting from D Du ua al l 3 34 41 12 2 or manifold gauge set For additional information refer to Chapter 2 Evacuating Service Hoses pNever drop a recovery tank onto scale This may damage scale assembly pAlways oil seals before connection to any tank filter or fitting A leaky connection or no flow condition may res...

Page 44: ...sidered the starting point Refer to the Moisture Indicator Chart below Complete the Master Filter Maintenance Schedule on the following two pages to track when to change master filter Moisture Indicator Figure 3 1 Moisture Indicator Chart Moisture Indicator Chart Indicator Color Model Temperature 75 F 24 C 100 F 38 C 125 F 52 C Purple R 12 1 4 ppm 2 5 ppm 4 ppm Very Dry R 134a 20 ppm 35 ppm 60 ppm...

Page 45: ...3 3 Master Filter Maintenance Schedule R12 Hour Meter Reading Next Change Date Starting Point Meter Reading M Ma ai in nt te en na an nc ce e ...

Page 46: ...3 4 M Ma ai in nt te en na an nc ce e ...

Page 47: ...3 5 M Ma ai in nt te en na an nc ce e Master Filter Maintenance Schedule R134a Hour Meter Reading Next Change Date Starting Point Meter Reading ...

Page 48: ...Read understand and follow S Sa af fe et ty y I In nf fo or rm ma at ti io on n in the front of this manual 1 Evacuate service hoses For additional information refer to Chapter 2 Evacuating Service Hoses 2 Remove power cord from wall outlet 3 Release hook and loop strap securing master filter Figure 3 2 Master Filter 4 Unscrew two hose fittings from master filter 5 Remove master filter 3 3 3 3 Dis...

Page 49: ... this kit Maintaining the Pump 1 Perform a Recycle on the service hoses if necessary For additional information refer to Chapter 2 Evacuating Service Hoses 2 Unplug D Du ua al l 3 34 41 12 2 from electrical outlet 3 Remove screws holding top cover 4 Remove top cover Figure 3 3 Pump A Outlet Line Connection at Pump B Input Line Connection at Pump C Outlet Line Tube D Process Line Tube E Input Line ...

Page 50: ...f approximately 9 oz of oil is not recovered repeat step 9 11 Use plastic bottle supplied with oil change kit to pour 9 3 oz 275 cc of 3GS compressor oil part number 681 0179 2 into input port of pump top port 12 Reinstall pump and four bolts at base 13 Install new O rings on ends of the tubing and hose assemblies 14 Place a small amount of compressor oil on O rings and reinstall tubing assemblies...

Page 51: ...t properly Tighten fitting finger tight connected to recovery tank No refrigerant in tank Fill tank with refrigerant Machine does not draw Loose hose connection Tighten loose hose a vacuum connections Oil drain valve open Close oil drain valve Hissing noise from oil Oil drain valve open Close oil drain valve separator during recycle and or vacuum mode Refrigerant losses from Leaky hand valve s on ...

Page 52: ... 4719 0055 02 134a Anti blowback Valve Optional Accessories For R 12 Part Number Description EAK0095C01AB Master Drier Kit EAH0013C21A Gauge Assembly with hoses Europe EAH0013C22A Gauge Assembly with hoses Japan 0647 281 01 GM Adaptor for A F U and W Bodies ACT 111B 2 oz Oil Charge Kit for R 12 For R 134a Part Number Description EAK0095C02AB Master Drier Kit EAK0027C00AS Vehicle Adaptor Repair Kit...

Reviews: