Carrier 48EK, 48EW, 48AW Evaporator Fan Service and Replacement, Evaporator-Fan Motor Replacement

Page 92

5.Be sure that hub flanges, flex members, spacer, and hard- ware are clean and free of oil.

6.Place the flanges onto the shafts with the hub facing out- ward. Do not tighten the set screws at this time.

7.Outside of the unit, assemble the flex members to the cen- ter drive shaft with 4 bolts and nuts. The flex members have collars that need to be inserted into the smaller hole of the drive shaft flange.

8.Assemble the flex member/drive shaft assembly to one of the shaft flanges, using 2 bolts and nuts. Slide the other shaft flange towards the assembly and assemble using 2 bolts and nuts. If the shafts are not misaligned, the collar in the flex member should line up with the shaft flange holes.

9.Torque nuts properly to 95 to 100 ft-lb. Do not turn a cou- pling bolt. Always turn the nut. Always use thread lubri- cant or anti-seize compound to prevent thread galling.

10.The ends of the shafts should be flush with the inside of the shaft flange. Torque the set screws to 25 ft-lb.

11.After assembly is complete, slowly rotate the shafts by hand for 30 to 60 seconds.

12.Tighten the bearing mounting bolts, using care not to place any loads on the shaft which would cause flexure to the shafts.

13.Reinstall drive belts. (Refer to Belt Tension Adjustment section below.)

14.Visually inspect the assembly. If the shafts are overly mis- aligned, the drive shaft flange will not be parallel with the shaft flanges.

15.Recheck nut torque after 1 to 2 hours of operation. Bolts tend to relax after being initially torqued.

Evaporator Fan Service and Replacement

1.Turn off unit power supply.

2.Remove supply-air section panels.

3.Remove belt and blower pulley.

4.Loosen setscrews in blower wheels.

5.Remove locking collars from bearings.

6.Remove shaft.

7.Remove venturi on opposite side of bearing.

8.Lift out wheel.

9.Reverse above procedure to reinstall fan.

10.Check and adjust belt tension as necessary.

11.Restore power to unit.

Belt Tension Adjustment — To adjust belt tension:

1.Turn off unit power supply.

2.Loosen motor mounting nuts and bolts. See Fig. 69.

3.Loosen fan motor nuts.

4.Turn motor jacking bolts to move motor mounting plate left or right for proper belt tension. A slight bow should be present in the belt on the slack side of the drive while running under full load.

5.Tighten nuts.

6.Adjust bolts and nut on mounting plate to secure motor in fixed position. Recheck belt tension after 24 hours of operation. Adjust as necessary. See Table 3 for proper tension values.

7.Restore power to unit.

Evaporator-Fan Motor Replacement

1.Turn off unit power supply.

2.Remove upper outside panel and open hinged door to gain access to motor.

3.Fully retract motor plate adjusting bolts.

4.Loosen the 2 rear (nearest the evaporator coil) motor plate nuts.

5.Remove the 2 front motor plate nuts and carriage bolts.

6.Slide motor plate to the rear (toward the coil) and remove fan belt(s).

7.Slide motor plate to the front and hand tighten one of the rear motor plate nuts (tight enough to prevent the motor plate from sliding back but loose enough to allow the plate to pivot upward).

8.Pivot the front of the motor plate upward enough to allow access to the motor mounting hex bolts and secure in place by inserting a prop.

9.Remove the nuts from the motor mounting hex bolts and remove motor.

10.Reverse above steps to install new motor.

Condenser-Fan Adjustment

1.Turn off unit power supply.

2.Remove fan guard.

3.Loosen fan hub setscrews.

4.Adjust fan height on shaft using a straightedge placed across venturi and measure per Fig. 70.

5.Fill hub recess with permagum if rubber hubcap is missing.

6.Tighten setscrews and replace panel(s).

7.Turn on unit power.

Fig. 69 — Belt Tension Adjustment

Fig. 70 — Condenser-Fan Adjustment

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Contents Installation, Start-Up Service Instructions Make Unit Duct Connections Instructions onRoof Curb 48AJ,AK020-030 and 48EJ,EK024-034 Units Roof Curb 48AJ,AK034-050 and 48EJ,EK038-048 Units Roof Curb 48AJ,AK060 and 48EJ,EK054-068 Units Page Base Unit Dimensions 48AJ,AK020-030 Base Unit Dimensions 48AJ,AK035-050 Base Unit Dimensions 48AJ,AK060 Base Unit Dimensions 48AW,AY020-030 Base Unit Dimensions 48AW,AY035-050 Base Unit Dimensions 48W,AY060 Base Unit Dimensions 48EJ,EK024-034 Base Unit Dimensions 48EJ,EK038-048 Base Unit Dimensions 48EJ,EK054-068 Base Unit Dimensions 48EW,EY024-034 Base Unit Dimensions 48EW,EY038-048 Base Unit Dimensions 48EW,EY054-068 AT Each Corner % Rigging Weights 48AJ,AK,AW,AY Units AT Each Corner % 48EJ,EW,EK,EYD02448EJ,EW,EK,EYD028 48EJ,EW,EK,EYD030Physical Data 48AJ,AK,AW,AY Units Unit 48AJ,AK,AW,AYQuantity Rows...Fins/in Physical Data 48EJ,EK,EW,EY Units Unit 48EJ,EK,EW,EY06D537 06EA250 06EA265 Quantity...Type Ckt 1, Ckt Operating Weights Evaporator Fan Motor Data Air Distribution Thru-the-BottomInstall Flue Hood Combustion Fan Housing LocationStages 48A,E Series Staged Gas ImplementationNumber of Stages Model Number Position Heat Size Htstgtyp Thermistor Designations Supply-Air Thermistor Connections Indoor Air Quality Sensor Configuration Make Electrical Connections CCN COMSIO DIPUnbalanced 3-Phase Supply Voltage Electrical Data 48AJ,AK,AW,AY UnitsMin Max RLA LRAQty 30.8/28.0 180.5/177.7 225/225 236.3/230.9 Electrical Data 48EJ,EK,EW,EY Units Range Exhaust FAN MotorFLA LRA MCA Mocp EW,EYFLA LRA MCA Mocp EW,EY 54.0 23.6 41.6 RLA FLANEC Field Power Wiring Connections GND GroundCCB EquipGND IFCOFC Indoor-Fan Relay Terminal Block Carrier Comfort Network Indoor-Fan CircuitCCN IFC Pesc CCN Connection Approved Shielded Cables Color Code RecommendationsMake Outdoor-Air Inlet Adjustments Space Temperature Averaging WiringAdding Seal Strip to Top of Hood Sides Adding Seal Strip to Sides of Hood Top Mounting Flange Mounting Angle With Tabs Attached to Filter Track Assembly Differential Enthalpy Control and Sensor Psychrometric Chart for Enthalpy Control Control Control Point Curve APPROX. DEGBarometric Relief Damper and Power Exhaust Mounting Details 120.5 119.5 48EJ,EK,EW,EY058-068 Unit Size80.5 79.5 48EJ,EK,EW,EY024-054 Motormaster III Sensor Location 48EJ,EK,EW,EY054-064 Field Modifications Side Return Air ConversionSTART-UP Pressure Control Signal VFD SET Point In. wgCarrier Default Program Parameter Values Parameter Group Default ValueMotor Standard Efficiency High Efficiency Typical Factory Wiring Optional Field Wiring Building Pressure Signal Level DIP Switch Configuration SettingOpen ClosedAirflow DIP Switch Factory SettingsFan Performance, 48AJ,AK020-030 Vertical Discharge Units Fan Performance, 48AJ,AK035 Vertical Discharge Units 16,00017,000 18,000Fan Performance, 48AJ,AK040,050 Vertical Discharge Units 19,00020,000 17,000 18,000 19,000 20,000Fan Performance, 48AJ,AK060 Vertical Discharge Units Fan Performance, 48AW,AY020-030 Horizontal Discharge Units 11,000 12,000 13,000 14,000 15,00013,000 14,000 15,000 16,000 17,000 18,000 Fan Performance, 48AW,AY035 Horizontal Discharge Units17,000 18,000 16,000 17,000 18,000 19,000 20,000 Fan Performance, 48AW,AY040,050 Horizontal Discharge Units19,000 20,000 Fan Performance, 48AW,AY060 Horizontal Discharge Units 26,000 27,000Fan Performance, 48EJ,EK024,034 Vertical Discharge Units Fan Performance, 48EJ,EK038,044 Vertical Discharge Units 19,000 20,000 Available External Static Pressure in. wgRpm Bhp 000 1066 1096 1125 15,000 16,000 17,000 18,000 19,000 20,000000 1086 11.10 1114 11.61 1141 12.14 Fan Performance, 48EJ,EK048 Vertical Discharge UnitsRpm Bhp Fan Performance, 48EJ,EK054-068 Vertical Discharge Units 10,000 949 13.81 970 14.54 990 15.26Fan Performance, 48EW,EY054-068 Horizontal Discharge Units 26,000 27,000 Available External Static Pressure in. wg10,000 956 12.99 976 13.66 996 14.32 20,000 21,000 22,000 23,000 24,000 25,000 26,000 27,000Airflow LOW Speed Medium Speed High Speed ESPMotor Limitations Air Quality LimitsSequence of Operation User Defined Set Points Software Control Link PointsPage Heat Interlock Relay Wiring COM CommonStaged Gas System Components Stage Gas System Inputs/OutputsFunction Location Input DescriptionNavigator Display Navigator Display Menu StructureOccupied Morning Temperature Software Heat Version EnabledDEG. F Reset ConditionField-Supplied Smoke Detector Wiring Smoke Control Modes Cooling Capacity Staging Table, CV Units with 2 CompressorsDevice Pressurization Smoke Purge Evacuation Fire Shutdown StagesService Typical Gas Heating Section Lubrication Manufacturer LubricantEvaporator Fan Service and Replacement Belt Tension Adjustment To adjust belt tensionEvaporator-Fan Motor Replacement Condenser-Fan AdjustmentGas Valve Adjustment Cooling Charging Chart 48EJ,EK,EW,EY024-034Cooling Charging Chart 48EJ,EK,EW,EY054-068 Protective Devices Voltage Wire Indoor Voltage Wire06D-537 208/230-3-60 Following fan motors have two 20 HP 208/230-3-60Typical 48EK VAV 24-V Control Circuit Typical CV 24-V Control Circuit Typical 48EK VAV 115-V Control Circuit Typical 48EJ CV 115-V Control Circuit 101 102 Troubleshooting Typical Refrigerant Circuiting 48AJ,AK,AW,AY027,030 Typical Refrigerant Circuiting 48AJ,AK,AW,AY035 Typical Refrigerant Circuiting 48EJ,EK,EW,EY038,044 Typical Refrigerant Circuiting 48AJ,AK,AW,AY040,050 Typical Refrigerant Circuiting 48EJ,EK,EW,EY048 Typical Refrigerant Circuiting 48EJ,EK,EW,EY054 Typical Refrigerant Circuiting 48AJ,AK,AW,AY060 Typical Refrigerant Circuiting 48EJ,EK,EW,EY064 Typical Refrigerant Circuiting 48EJ,EK,EW,EY068 IGC Control Heating and Cooling IGC Control Board LED Alarms Control Board LED AlarmsO Channel Designations Base Module CV O Channel Designations Base Module VAVTerminal no Assignment IAQService Training START-UP Checklist General
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48EJ, 48AJ, 48AK, 48EK, 48AY020-060 specifications

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