INSTALLATION INSTRUCTION

Transcription

1 INSTALLATION INSTRUCTION 0 F LOW AMBIENT ACCESSORY MODELS 2LA , 3546 & 3658 (208, 230, 460 & 575 VOLT APPLICATIONS) Supersedes: N5.6V (1091) N5.6V (1193) FOR 15, 20 & 25 TON COOLING CAPACITY SINGLE PACKAGE AIR CONDITIONERS GENERAL These single package air conditioners are only designed to operate at ambient temperatures down to 25 F. This accessory will insure safe operation at ambient temperatures down to 0 F. This instruction provides all the necessary information to properly field-install a low ambient accessory on the single package air conditioners indicated above. All components, including condenser motor, temperature control, wires and mounting hardware are supplied in each accessory. Refer to Table 1 for control application data and to Table 2 for the components that are supplied in the respective accessory. TABLE 1 -CONTROL APPLICATION DATA ACCESSORY MODEL NO. 2LA LA LA INSTALLATION IN 180 & 240 MBH UNITS Install the low ambient accessories as follows: 1. Disconnect all electrical power to the unit. VOLTAGE 208V & 240V 480V 600V 2. Replace the #1 condenser fan motor (located over the compressor compartment, as shown in Figure 1) with the motor supplied in the Accessory. To gain access to the existing motor, the fan grille must first be removed. Loosen the two screws on the fan hub and remove the fan. Disconnect the wires at the motor, loosen the clamp securing the motor, then remove the motor. CAUTION: Exercise care when handling the fan to insure that its blades do not get bent or knocked out of balance. 3. Check the new dual voltage motor wiring and make the appropriate 208, 230 or 460 volt connection per the diagram on the motor. The motor for 575 volt operation has a dedicated voltage, therefore no wiring is required. 4. Install the new motor into the motor mount. Re-connect the following wires to the motor terminals: Terminal T1 T2 T3 Wire 146/Brown 145/Red 147/Orange Note: Motor terminals may be marked L1/L2/L3 or 1/2/3. 5. Secure the motor in its mounting with the existing strap. Replace the fan and the fan grille. NOTE: When re-installing the fan onto the motor shaft,position it so that the bottom of the fan blades are below the bottom of the fan orifice as specified in Figure 2. TABLE 2 - COMPONENTS SUPPLIED WITH KIT ITEM QTY. PART NO. DESCRIPTION VOLTAGE ACCY. 2LA047* Condenser 208/240/480V *03425, * Motor** 600V * V, 240V * * Transformer (4T) 480V * V * * Contactor (LAR) 4* Capacitor 208/230/480V *03425 *03546 (2RC) V * Temperature Control (TLA2) Wiring Label 180/240 MBH Wiring Label 300 MBH Accessory Instruction - Form N5.6V * These items are supplied factory mounted on a component plate assembly. ** All motors are single phase, 1 HP and have a nominal speed of 1100 RPM, a 1.0 service factor, a 56 frame, ball bearings and inherent protection. CONDENSER DISCHARGE FAN MOTOR NO. 1 CONDENSER DISCHARGE FAN MOTOR NO. 2 FUSE BLOCK CONTACTORS COMPONENT ASSEMBLY PLATE (25 TON) COMPONENT ASSEMBLY PLATE (15 & 20 TON) CONTROL BOX COVER (HINGED) ELECTRICAL CONNECTOR TEMP. CONTROL TLA2 FRONT VIEW FIG. 1 - UNIT CONTROL SECTION CONTROL BOX (ACCESS PANEL & BOX COVER NOT SHOWN)

2 FAN GRILLE FAN ORIFICE FAN 1-1/8" (15 TON) 1-3/4" (20 & 25 TON) MOTOR STRAP MOTOR SUPPORT FIG. 2 - CONDENSER FAN ADJUSTMENT 6. Remove the control box access panel from the unit and open the hinged cover on the control box. Refer to Figure Mount the component plate assembly (mounting bracket including a transformer, a capacitor and a contactor) to the bottom RH corner on the inside of the control box per the respective location as shown in Figure 1. Using the holes in the bracket flanges as a template, drill 9/64" dia.(#26 drill) holes into the bottom or side plate of the control box and secure with the 5/8" long tapping screws provided. CAUTION: Before mounting the plate assembly, insure that its location will allow the control box cover to close properly. Exercise care when drilling holes so that existing wiring and components are not damaged. 8. Place the temperature control TLA2 into the open chamber at the bottom of the control box.the control leads must be passed up through the electrical connector to the inside of the control box. Wrap the leads with approximately three layers of electrical tape where they come in contact with the connector. 9. Wiring of this accessory requires modification of the high and low voltage circuitry. Refer to Figure 3, the unit wiring labels inside of the control box cover, and the accessory wiring label supplied in this kit per the following steps: a. Remove wires 228/Blue and 401/Blue from 4M contactor coil and replace with the BROWN lead from temperature control TLA2. Clip the terminals from the wires just removed and strip the ends approximately 1/2". b. Join wires 228/Blue and 401/Blue with the RED lead from temperature control TLA2 using a wire nut provided. c. Connect the BLACK lead from temperature control TLA2 to the coil connection on the LAR contactor. d. Connect wire 900 (provided in kit) from the line side of contactor 4M (at 4M-1) to the 2RC capacitor. Relocate wire 145/Red from the load side to the line side of 4M-1. This makes wires 900, 145/Red and 130/Red common at the line side of 4M-1. Note: Wire 130/Red is replaced with wire 516/Red on 575V Models with 54kW or 72kW Electric Heat. e. Remove wire 147/Orange from the load side of the 1M contactor and connect to the identified terminal on the 2RC capacitor. f. Connect wires 901 and 902 (provided in kit) from the 4M Connect wire 900 (provided in kit) between the 4M contactor and the 2RC capacitor. Connection at the UNIT UNIT VOLT REQ D. TRANSF. VOLT. TAP 15T 208 BLUE 15T 230 YELLOW 15T 460 YELLOW 15T 575 ORANGE UNIT UNIT VOLT FIG. 3 - TYPICAL ELEMENTARY DIAGRAM REQ D. TRANSF. VOLT. TAP 20 & 25T 208 ORANGE 20 & 25T 230 BLUE 20 & 25T 460 BLUE 20 & 25T 575 TAN contactor must be made to the same terminal currently occupied by wire 130. Relocate wire 145/R from the opposite side of the contactor to this same terminal. Wire 145/R must be on terminal common with wire 900.contactor to the LAR contactor. Connect wire 901 from the load side of 4M-2 to the line side of LAR-1 (making wire 901 common with wire 146/Brown). Connect wire 902 from the line side of 4M-2 to the line side of LAR-2 (making wire 902 common with wire 104/Brown). Note: Wire 104/Brown is replaced with wire 517/Brown on 575V Models with 54kW or 72kW Electric Heat. g. Connect wire 903 (provided in kit) between the remaining coil connection on the LAR contactor and the 4TB terminal block. Connect wire 903 (provided in kit) between the remaining coil connection on LAR contactor and the 4TB terminal block. CAUTION: Wire 903 at the 4TB terminal block must be connected to the grounded or common side. 10. Check the lead from the LAR contactor to the 4T transformer and connect to the appropriate voltage tap location. Refer to Figure 3 or the accessory wiring label provided. Tape off all unused lead taps on the transformer. 11. Recheck all wiring for proper connections. Check to insure that connector clamps are tightened and that all wiring is placed in a neat workmanlike manner. 12. Attach the accessory wiring label provided in this kit to an open area inside of the control box cover. Do not overlap any existing labels on the cover. 13. Close the control box cover and replace the control box access panel. 2 Unitary Products Group

3 14. Restore electrical power to the unit. INSTALLATION IN 300 MBH UNITS Install the low ambient accessories as follows: 1. Disconnect all electrical power to the unit. 2. Replace the #1 condenser fan motor (located over the compressor compartment, as shown in Figure 1) with the motor supplied in the Accessory. To gain access to the existing motor, the fan grille must first be removed. Loosen the two screws on the fan hub and remove the fan. Disconnect the wires at the motor, loosen the clamp securing the motor, then remove the motor. CAUTION: Exercise care when handling the fan to insure that its blades do not get bent or knocked out of balance. 3. Check the new dual voltage motor wiring and make the appropriate 208, 230 or 460 volt connection per the diagram on the motor. The motor for 575 volt operation has a dedicated voltage, therefore no wiring is required. 4. Install the new motor into the motor mount. Re-connect the following wires to the motor terminals: Terminal T1 T2 T3 Wire 146/Blue 145/Black 147/Orange Note: Motor terminals may be marked L1/L2/L3 or 1/2/3. 5. Secure the motor in its mounting with the existing strap. Replace the fan and the fan grille. NOTE: When re-installing the fan onto the motor shaft,position it so that the bottom of the fan blades are below the bottom of the fan orifice as specified in Figure Remove the control box access panel from the unit and open the hinged cover on the control box. Refer to Figure Mount the component plate assembly (mounting bracket including a transformer, a capacitor and a contactor) to the bottom RH corner on the inside of the control box per the respective location as shown in Figure 1. Using the holes in the bracket flanges as a template, drill 9/64" dia.(#26 drill) holes into the bottom or side plate of the control box and secure with the 5/8" long tapping screws provided. CAUTION: Before mounting the plate assembly, insure that its location will allow the control box cover to close properly. Exercise care when drilling holes so that existing wiring and components are not damaged. 8. Place the temperature control TLA2 into the open chamber at the bottom of the control box.the control leads must be passed up through the electrical connector to the inside of the control box. Wrap the leads with approximately three layers of electrical tape where they come in contact with the connector. 9. Wiring of this accessory requires modification of the high and low voltage circuitry. Refer to Figure 3, the unit wiring labels inside of the control box cover, and the accessory wiring label supplied in this kit per the following steps: a. Remove wires 228/Purple and 401/Purple (found on D*CV300* models only) from 4M contactor coil and replace with the BROWN lead from temperature control TLA2. Clip the terminals from the wires just removed and strip the ends approximately 1/2". b. Join wires 228/Purple and 401/Purple (found on D*CV300* models only) with the RED lead from temperature control TLA2 using a wire nut provided. c. Connect the BLACK lead from temperature control TLA2 to the coil connection on the LAR contactor. d. Connect wire 900 (provided in kit) from the line side of contactor 4M (at 4M-1) to the 2RC capacitor. Relocate wire 116/Black from the load side to the line side of 4M-1. This makes wires 900, 116/Black and 130/Red common at the line side of 4M-1. e. Remove wire 142/Orange from the load side of the 1M contactor and connect to the identified terminal on the 2RC capacitor. f. Connect wires 901 and 902 (provided in kit) from the 4M contactor to the LAR contactor. Connect wire 901 from the load side of 4M-2 to the line side of LAR-1 (making wire 901 common with wire 117/Blue). Connect wire 902 from the line side of 4M-2 to the line side of LAR-2 (making wire 902 common with wire 135/Brown). g. Connect wire 903 (provided in kit) between the remaining coil connection on the LAR contactor and the4tb terminal block. CAUTION: Wire 903 at the 4TB terminal block must be connected to the grounded or common side. 10. Check the lead from the LAR contactor to the 4T transformer and connect to the appropriate voltage tap location. Refer to Figure 3 or the accessory wiring label provided. Tape off all unused lead taps on the transformer. 11. Recheck all wiring for proper connections. Check to insure that connector clamps are tightened and that all wiring is placed in a neat workmanlike manner. 12. Attach the accessory wiring label provided in this kit to an open area inside of the control box cover. Do not overlap any existing labels on the cover. 13. Close the control box cover and replace the control box access panel. 14. Restore electrical power to the unit. OPERATION N5.6V At ambient temperatures above 60 F, the condenser fan motors will run at full speed (approx.1075 RPM) during both single and two stage unit operation. As the ambient temperature drops to 60 F, temperature control TLA, provided on the basic unit, will open de-energizing fan motor #2. Fan motor #1 will continue to run at full speed. When the ambient temperature then drops to 25 F, temperature control TLA2 will switch, energizing LAR contactor. This applies the tapped voltage from the 4T transformer to the #1 fan motor. The resulting reduced voltage slows the speed of this motor to allow unit operation down to 0 F. As the ambient temperature rises, the above operating sequence is reversed and both condenser fans are restored to full operation. Unitary Products Group 3

4 FIG /240 MBH LOW AMBIENT ACC Y POWER WIRING 4 Unitary Products Group

5 FIG /240 MBH LOW AMBIENT ACC Y CONTROL WIRING Unitary Products Group 5

6 FIG MBH LOW AMBIENT ACC Y POWER WIRING 6 Unitary Products Group

7 300 MBH VARIABLE AIR MODELS 300 MBH CONSTANT AIR MODELS VARIABLE AIR MODELS ONLY 300 MBH VARIABLE AIR MODELS VARIABLE AIR MODELS ONLY 300 MBH CONSTANT AIR MODELS FIG MBH LOW AMBIENT ACC Y CONTROL WIRING Unitary Products Group 7

8 Subject to change without notice. Printed in U.S.A. Copyright by Unitary Products Group All rights reserved. Unitary Products Group 745 Industrial Parkway West Elyria OH Code: SBY, L, F N5.6V