Section 3- Repair and Calibration Procedures

Transcription

1 Section 3- Repair and Calibration Procedures 1. Refrigerant Removal Procedures 2. Scale/PC Board Recalibration Procedure 3. PC Board Configuration Procedure of AR Scale Tare Procedure 5. Gauge Calibration Procedure 6. Regulator Adjusting Procedures 7. Mechanical Connections Tightening and Loosening Procedures 8. Brazing Procedures Note: If there is any question on how to perform these procedures, please consult factory S3-1 1

2 1. Refrigerant Removal Procedure There are two different procedures, Low Side Refrigerant Removal and Complete Refrigerant Removal, on how to remove refrigerant from an AR400. Which procedure to use depends upon the location of the defective part and the current status of the unit. If there is any doubt, always use the Complete Refrigerant Removal procedure. Note: If the compressor is not functioning you must use the Complete Refrigerant Removal procedure. Low Side Refrigerant Removal Procedure Step 1: Open both the Low and High Side Manifold valves. Step 2: Close the Liquid Valve on the Storage Tank. Step 3: Connect the Low Side and High Side service hoses together. Step 4: Run Mode 3 (CHARGE). Program 5 lbs of charge. Step 5: Turn off the unit when both Low and High Side manifold gauges read a vacuum. Disconnect power. Unit is ready for service. When the unit is run in the CHARGE mode with the Storage Tank Liquid Valve closed and the Low and High Side service hoses connected to each other, the entire low side of the AR400 will be pulled into a vacuum. Complete Refrigerant Removal Procedure Step 1: Open both the Low and High Side Manifold valves. Step 2: Close both Storage tank valves. Step 3: Connect the Low Side and High Side service hoses together. Step 4: Use CPS pinch off pliers (TLPP) to seal the Tank Vapor hose. Disconnect this hose from the Tank. Step 5: Connect the Tank Vapor hose to a separate recovery unit (such as the CR500) as shown if Figure 1. Step 6: Release pinch off pliers. Step 7: Run Mode 3 (CHARGE). Program 5 lbs of charge. Step 8: Start the refrigerant recovery unit. Step 9: Wait until the Low Side Manifold, High Side Manifold and Purge Gauges pull into a vacuum. This should take about 10 minutes. Step 10: Turn off both the AR400 and the separate recovery unit when acceptable vacuum level is reached. Unit is ready for service Refrigerant Recovery Unit CPS Pinch Off Pliers VAPOR VALVE RECOVERY TANK VAPOR HOSE FROM AR400 SCALE AR400 Figure 1 S3-2 2

3 2. Scale/PC Board Recalibration Procedure Any time a new scale or PC Board is installed into the AR400, the calibration procedure must be performed to ensure weight reading accuracy. After installation is complete, follow this procedure to properly calibrate the AR400 PC Board and Scale. Failure to do this procedure will lead to improper operation of the AR400. Calibrate as follows: While pushing down on the START key, turn on the unit s power switch. A SELF-TEST message will come up as soon as power is applied to the unit. After a few seconds while the unit is performing internal operations, the following message will be displayed: SEE SERVICE MANUAL (STOP) TO EXIT Push the START key to enter into the calibration mode. Once this key is depressed, the message RECALIBRATE 1 is displayed. Empty the platform and press down the START key. This sets the zero level of the scale. Now the message Press down the START key again. Now the message RECALIBRATE 2 xxxxx RECALIBRATE lb oz is displayed. Place a 40, 50, or 60 lb. Class F, calibrated, NIST traceable weight centered on the platform. Push down the + ARROW key until the displayed weight matches the calibration load. If the weight entered goes over that of the load, press down the - ARROW key until the desired weight is displayed. Once there is no vibration or shaking on the platform, press down the SET key. This sets the SPAN of the scale. The message RECALIBRATE 2 xxxxx yyyyy is displayed. Write down the first set of numbers (xxxxx) in the Low End Count box. Write down the second set of numbers (yyyyy) in the High End Count box. Save for future reference. Press down the SET key again. The unit s scale is now calibrated. Before we can check the calibration, we will need to reconfigure the AR400 Microprocessor. Turn off power to unit. Proceed to AR400 Microprocessor configuration. NOTE: The unit must be configured after Recalibrating or the unit will not function properly. 3. PC Board Configuration Procedure of AR400 Push down SET key while turning on power back on to unit. The LCD will display will read: DUAL CONFIG SET-YES STOP-NO Push to SET key to accept Dual Configuration. The LCD will now read: INTERNAL VAC STOP-NO SET-YES S3-3 If vacuum pump installed, push the STOP key. If no vacuum pump installed, push the SET key. 3

4 The LCD will now read: EXTERNAL VAC STOP-NO SET-YES If vacuum pump installed, push the SET key. If no vacuum pump installed, push the STOP key. The LCD will now read: R-134 EMPTY TANK WEIGHT 27LBS 8.00 OZ Push the + ARROW key to adjust this setting to 27 lbs 8.00 oz. Push the SET key to accept. The LCD will now read: R-134 MAX REF WEIGHT 38LBS 0.00 OZ Push the + ARROW key to adjust this setting to 38 lbs 0.00 oz. Push SET key to accept. The LCD will now read: R-12 EMPTY TANK WEIGHT 27LBS 8.00 OZ Push the + ARROW key to adjust this setting to 27 lbs 8.00 oz. Push the SET key to accept. The LCD will now read: R-12 MAX REF WEIGHT 38LBS 0.00 OZ Push the + ARROW key to adjust this setting to 38 lbs 0.00 oz. Push SET key to accept. The LCD will now read: REF ID INSTALLED? SET-YES STOP-NO Push the STOP key to decline this option. The LCD will now read: PRINTER INSTALLED? SET-YES STOP-NO Push the STOP if no printer is installed. Push the SET key if a printer is installed. The LCD will now read: SELECT REFRIGEANT R R12 Push the + ARROW key for R134 operation. With the 50lb weight on scale, the display should read PUSH MODE KEY 22lbs 8.00 ounces Compare the actual weight reading with the empty tank weight (22 lbs 8.00 ounces). The actual reading should be within + or 2 oz. Please note this weight is based on the empty tank weight being 27 lbs 8.00 oz. Turn off power to unit. Calibration and configuration complete. Danger: If is extremely important that the correct values for the Empty Tank Weight and Maximum Refrigerant Weight be inputted correctly. These settings control the Tank Full Limit cutout. The wrong values could allow the unit to overfill the storage tank. Overfilling of the recovery tank may cause a violent explosion resulting in severe injury or even death. Use only CPS approved storage tanks on the AR400. DO NOT USE A NON-CPS APPROVED TANK with this unit. S3-4 4

5 4. Scale Tare Procedure Select Mode 9C. Follow the directions on the LCD. Once Mode 9C is chosen, the LCD should read: REMOVE TANK PUSH SET SCALE PLATFORM Remove the tank from the Scale Platform. No weight should be applied to the scale platform. Push the START key. The LCD display will now read: REPLACE TANK PUSH STOP Place the tank back on the scale. Push the START-2 key. The LCD will read: SELECT REFRIGEANT R R12 Push the + ARROW key for R134 operation. The LCD will read: PUSH MODE KEY XX LB XX.XX OZ Check to see if the tare procedure was properly performed by: 1. Remove the storage tank from the scale platform. 2. The weight reading should be equal to the empty tank weight setting with a tolerance of +/- 2 ounces. See Microprocessor Configuration on Empty Tank Weight Settings. If the reading is not within limits, repeat the TARE Procedure. 5 S3-5

6 5. Gauge Calibration Procedure It will be necessary to recalibrate the Low Side Manifold, High Side Manifold, and Purge gauges periodically. The following will discuss how to check the gauges and recalibrate them if necessary. Low and High Side Manifold pressure gauges. Read the Low and High Side Manifold gauges. If pressure is present, proceed to run MODE 1 until the unit s LCD reads RECOVER COMPLETE. Remove the Low Side and High Side Service hoses. Always use caution when removing hoses. Always expect refrigerant to be present. Removing the hoses allows both gauges to see atmospheric pressure. The reading on the gauge should be 0 psig/mpa/kpa/bar. If the gauges read correctly, reconnect the Service hoses. Calibration not required If the gauges are not correct, remove the gauge lens cover. The lens cover is removed by turning counter-clockwise. Use a small flat tip screwdriver to turn the pressure gauge adjustment screw (located on the face of the gauge) until the gauge pointer reads 0 psig/mpa/kpa/bar. Repeat this adjustment for both gauges. ] S3-6 6

7 Purge Gauge The Purge gauge will be calibrated by comparing it to the Low Side Manifold gauge. To ensure accuracy, it will be necessary to first calibrate the Low Side Manifold gauge as discussed above. Run MODE 6 (QUICK CHARGE). Program 3 lbs of charge. Follow the directions on the LCD. Once the Low Side Manifold gauge stabilizes, compare it to the Purge gauge. The Low Side Manifold gauge should now read the same pressure source as the Purge gauge. If the Purge gauge reads the same as the Low Side Manifold gauge, run MODE 1 to clear the service hoses. Calibration is not required. If the Purge gauge read higher or lower than the Low Side Manifold gauge, remove the gauge lens cover. The lens cover is removed by turning counter-clockwise. Use a small flat tip screwdriver to turn the pressure gauge adjustment screw (located on the face of the gauge) until the gauge pointer reads the same as the Low Side Manifold gauge. Calibration is now complete. 6. Regulator Adjusting Procedures The AR400 is equipped with a constant pressure regulator. This prevents overloading of the compressor under high temperature conditions. The following is the procedure to set the constant pressure regulator: Turn the adjustment nut on top of the regulator clockwise until it bottoms out. Turn the adjustment nut 3 turns counter-clockwise. The regulator is now set at a maximum of 80 psig. S3-7 7

8 7. Mechanical Connections Tightening and Loosening Procedures The AR400 uses 2 different types of mechanical connections. One will be a 1/8 pipe thread connection, where a 1/8 tapered male pipe thread is screwed into a 1/8 tapered female pipe thread fitting. The other is a ¼ flare connection, where a swivel ¼ female flare nut is screwed onto a ¼ male flare. Please review the descriptions and pictures of the different types of fittings used for these 2 types of connections. ¼ Flare Nut- the Solid brass swivel nut that connects either copper tubing or refrigerant hose to a ¼ male flare fitting. Standard Straight Brass Fitting- a brass fitting with 1/8 male pipe threads on one end and ¼ male flare fitting on the other. A 7/16 hex is located in the middle of this fitting. The 1/8 male pipe thread end is usually screwed into an aluminum or brass block. Standard 90 o Brass Fitting- a 90 degree elbow brass fitting with 1/8 male pipe threads on one end and ¼ male flare fitting on the other. The 1/8 male pipe thread end is usually screwed into an aluminum or brass block. Check Valve- the check valve assembly is built within a brass fitting with either ¼ male flare fitting or 1/8 male pipe thread. The AR400 utilizes 3 different styles of check valves. A ½ hex is located in the middle of this fitting. Refrigerant Hose Swivel Nut- recognized by the knurling around the swivel fitting. Contains a rubber seal. May be use as the hose fitting on the compressor suction port, otherwise disregard. 8 S3-8

9 The following will discuss the proper tightening and loosing procedure for the different types of connections used in the AR400. Flare Nut to Standard Straight Brass Fitting (the use of backup wrench required): This connection is the most common connection in the AR400. It is recognized by its small hex surface (7/16) on the Standard Brass Fitting. TIGHTENING PROCEDURE: The flare nut should be hand tightened to ensure proper threading. Use a 9/16 boxed end wrench to tighten the flare nut just until it is snug. Once snug, use the 7/16 backup wrench on the brass fitting (to prevent it from moving) while turning the flare nut an additional ¼ turn. Resistance should be felt when turning. 7/16 BACK UP WRENCH 9/16 WRENCH LOOSENING PROCEDURE: A 7/16-boxed end wrench will be needed as a back up wrench while loosening the flare nut with a 9/16-boxed end wrench. Flare Nut to Check Valve (use of backup wrench required): It is recognized by its ½ hex with an arrow pointing in the direction of flow. Note: It is very important not to over-tighten a check valve. This can deform the brass body and prevent the check valve from working properly. TIGHTENING PROCEDURE: The flare nut should be hand tightened to ensure proper threading. Use a 9/16 inch boxed end wrench to tighten the flare nut just until it is snug. Once snug, use the ½ inch backup wrench on the brass fitting (to prevent it from moving) while turning the flare nut an additional ¼ turn. Resistance should be felt when turning. LOOSENING PROCEDURE: A ½ inch boxed end wrench will be needed as a back up wrench while loosening the flare nut with a 9/16 inch boxed end wrench. ¼ Flare Nut to a ¼ Male Flare Fittings (other than check valves and Standard straight brass fittings) where backup wrench is not required: TIGHTENING PROCEDURE: The flare nut should be hand tightened to ensure proper threading. Use a 9/16 inch boxed end wrench to tighten the flare nut just until it is snug. Once snug, tighten the flare nut an additional ¼ turn. Resistance should be felt when turning. 9 S3-9

10 LOOSENING PROCEDURE: Loosen the flare nut with a 9/16 inch boxed end wrench. 1/8 MPT fitting to Aluminum Block The 1/8 male pipe thread is used on the Standard straight or 90 o brass fitting and check valves. TIGHTENING PROCEDURE: A small amount of sealant (use CPS recommended sealant) should be applied to the male pipe threads. Be careful not to apply the sealant inside the fitting. The sealant could plug up a solenoid valves and/or check valves. Hand-tighten the 1/8 male pipe thread fitting into the steel, aluminum, or brass female pipefitting. Once hand tight, use a 7/16 inch socket wrench (for standard straight brass fittings) or ½ inch socket wrench (for check valves) or crescent wrench (Standard 90 o brass fittings). Turn until resistance is felt. Do not over-tighten. NOTE: Place a cap over the ¼ male flare threads to protect them from damage. 10 S3-10

11 Gauge 1/8 MPT fitting to Aluminum Block The 1/8 male pipe thread is used on the connection end of all gauges. TIGHTENING PROCEDURE: A small amount of sealant (use CPS recommended sealant) should be applied to the male pipe threads. Be careful not to apply the sealant inside the fitting. The sealant could plug up a solenoid valves and/or check valves. Hand start the gauge threads into the aluminum block. Turn the gauge 4-5 turns once engagement starts. Make sure the gauge is facing forward (toward the valves) when making the 4 th turn. A 9/16 inch boxed end wrench (15mm for AR400E manifold gauges) will be required to complete this tightening process. 8. Brazing Procedures The AR400 has only 5 braze joints; three on the compressor assembly and two on the condenser coil assembly. It is recommended that 5% silver brazing rod be used on the condenser coil assembly. Flux is optional. The joint is copper to copper. It is recommended that 45% silver brazing rod be used on the compressor assembly connections. Flux must be used. The joint is a copper to steel with copper plating. Remove all refrigerant contained inside the AR400 unit. Disconnect all mechanical connections to the component to be brazed. Run dry nitrogen through the component while brazing. DANGER: Before brazing, the system needs to be evacuated and purged with nitrogen. Poisonous gasses can form in the presence of an open flame. Breathing of these gasses can lead to death. S