Carrier VECTOR 1550 Series Operation & Service Manual

62-61753-218-19reverse flush (opposite normal air flow) with cleanwater at mild pressure.A garden hose with spray nozzle is usually suffi-cient. Ensure drain lines are clean.c. Run unit until defrost mode can be initiated to checkfor proper draining from drain pan.Coil Replacementa. Remove the refrigerant charge. (Refer to section8.5.1).b. Ensure the unit is disconnected from the powersource and that SROS is in OFF position.c. Disconnect return air sensor (RAT) and removescreen. Remove upper louvered panel.d. Remove heater connection service access cover(see to Figure 2-3) and disconnect heaters.e. Disconnect and remove the defrost termination tem-perature sensor (DTT), evaporator outlet pressuretransducer (EVOP) and evaporator outlet tempera-ture sensor (EVOT). Disconnect air switch tubing.f. Disconnect and remove the evaporator expansionvalve coil. Remove suction line between coil stuband suction modulating valve and liquid line withEVXV body.g. Remove the mounting hardware from the coil.h. After defective coil is removed from unit, note loca-tion of heaters (dimension form right end), removeheaters and install on replacement coil.i. Install coil assembly by reversing above steps.j. Leak check, evacuate the unit and charge in ac-cordance with sections 8.5.2, 8.5.3 & 8.5.4.8.6.3 Condenser CoilCoil CleaningRemove all foreign material from the conden-ser/radiator coil by reversing the normal air flow. (Air ispulled in through the front and discharges over theengine.) Compressed air or water may be used as acleaning agent. It may be necessary to use warm wa-ter mixed with any good commercial dishwasher de-tergent. Rinse coil with fresh water if a detergent isused.Coil Replacementa. Remove the refrigerant charge. (Refer to section8.5.1).b. Drain engine coolant, refer to section 8.4.10 andremove coolant hoses.c. Remove the condenser grille.d. Unsolder discharge line, subcooler lines and liquidoutlet line.e. Remove coil mounting hardware and remove thecoil.f. Install replacement coil and solder connections.g. Leak check, evacuate the unit and charge in ac-cordance with sections 8.5.2, 8.5.3 & 8.5.4.h. Reconnect coolant hoses and refill engine coolant(Refer to section 8.5.1).8.6.4 Economizer Heat Exchangera. Remove the refrigerant charge. (Refer to section8.5.1).b. Ensure the unit is disconnected from the powersource and that SROS is in the OFF position.c. Remove insulation and clamps from economizer lineassemblies (refer to figure Figure 8-12).d. Remove liquid Injection Solenoid Valve, EconomizerSolenoid Valve and Unloader Solenoid Valve coils.e. Remove thermal expansion valve bulb.f. Unbraze the liquid injection line at either valve con-nection. Disconnect the economizer line at the un-loader solenoid valve and compressor economizerconnection, unbraze line from economizer heat ex-changer.g. Disconnect the liquid inlet line at the filter drier andunbraze line from economizer.h. Disconnect the liquid outlet line at the connectionjust above the economizer heat exchanger and un-braze line from economizer heat exchanger.i. Remove economizer heat exchanger, bolt replace-ment economizer heat exchanger in place andrebraze lines by reversing the previous steps.j. Procure new O-rings. Lubricate the O-rings, backside of sleeves and coupling nuts. Using a backupwrench at each connection torque as followsConnection Torque ValueFilter Drier 41 to 51 Nm(30 to 38 ft-lbs.)Unloader Solenoid Valve 81 to 89 Nm(60 to 66 ft-lbs.)Liquid Outlet Line 52 to 57 Nm(38 to 42 ft-lbs.)Compressor Economizer 32 to 36 Nm(24 to 27 ft-lbs.)k. Leak check, evacuate the unit and charge in ac-cordance with sections 8.5.2, 8.5.3 & 8.5.4.l. reinstall the thermal expansion valve bulb, valvecoils and insulation.m. Place unit back in service and check operation.