Carrier 50TJ016-028 Installation, Start-up And Service Instructions Manual

Also see for 50TJ016-028: Installation, Start-Up and Service Instructions Installation, Start-Up and Service Instructions

Contents

Belt Tension Adjustment — To adjust belt tension:1. Loosen fan motor bolts.2. Adjust belt tension:a. 016 Units: Move motor mounting plate up or downfor proper belt tension (13 mm [1⁄2 in.] deflection withone finger).b. 024,028 Units: Turn motor jacking bolt to move mo-tor mounting plate up or down for proper belt tension(10 mm [ 3⁄8 in.] deflection at midspan with one finger[4 kg (9 lb) force]).3. Tighten nuts.4. Adjust bolts and nut on mounting plate to secure motorin fixed position.Condenser-Fan Adjustment50TJ016 UNITS (Fig. 25)1. Shut off unit power supply.2. Remove access panel(s) closest to the fan to be adjusted.3. Loosen fan hub setscrews.4. Adjust fan height on shaft using a straightedge placed acrossthe fan orifice.5. Tighten setscrews and replace panel(s).6. Turn on unit power.50TJ024,028 UNITS (Fig. 26)1. Shut off unit power supply.2. Remove fan top-grille assembly and loosen fan hub screws.3. Adjust fan height on unit, using a straightedge placed acrossthe fan orifice.4. Tighten setscrews and replace rubber hubcap to preventhub from rusting to motor shaft.5. Fill hub recess with permagum if rubber hubcap ismissing.Economizer Adjustment — See Tables 16 and 17 forcheckout and enthalpy simulation. Make certain the outdoor-air damper is fully closed and the return-air damper is fullyopen before completing the following steps.1. Turn on power to the unit.2. Turn the thermostat fan switch to the ON position. Thedamper will go to the vent position.3. Adjust the vent position with the minimum damper po-sition adjustment on the module. See Fig. 15.4. Set the system selector switch to COOL position and setthe cooling temperature selector to its lowest setting.NOTE: The cooling mode may also be simulated by re-moving the thermostat wires from terminals Y1 and Y2and installing a jumper between terminals R and Y1.Refer to unit label diagram for terminal locations.5. Set the outdoor-air thermostat (OAT) located in the econo-mizer section of the unit (see Fig. 14) to 23.9 C (75 F).6. If the outdoor temperature is below 23.9 C (75 F), theeconomizer will control the mixed air with the mixed-air sensor. If the outdoor air is above 23.9 C (75 F), placea jumper around the contacts of the OAT.7. Jumper terminal T to terminal T1 on the module (seeFig. 15). The economizer will go to the full open po-sition. The outdoor-air damper will go to the full openposition, and the return-air damper will go to the fullclosed position.8. Adjust mechanical linkage, if necessary, for correct po-sitioning. It may be necessary to remove the filters toadjust the linkage.9. Remove the jumper from around the contacts of the OATif installed in Step 6. Remove the jumper from termi-nals T and T1 installed in Step 7.10. If the cooling mode was simulated to operate the unit inStep 4, remove the jumper and reconnect the thermostatwires to terminals Y1 and Y2.Power Failure — Dampers have a spring return. In eventof power failure, dampers will return to fully closed positionuntil power is restored. Do not manually operate econo-mizer motor.Refrigerant Charge — Amount of refrigerant chargeis listed on unit nameplate and in Tables 1A and 1B. Referto Carrier GTAC II; Module 5; Charging, Recovery, Recy-cling, and Reclamation section for charging methods andprocedures.Unit panels must be in place when unit is operating dur-ing charging procedure.Table 16 — Economizer Checkout ProceduresTEST PROCEDURE RESULTSA. Disconnect power atTR and TR1.Disconnect jumperbetween P andP1. See Fig. 15.B. Jumper TR to 1.C. Jumper T1 to T.D. Disconnect outdoor-airthermostat connectionsfrom S O and +.Factory-installed800 ohm resistorshould remain connectedto SR and +.E. Reconnect power toterminals TR and TR1. 1. LED (light-emitting diode)should be off.2. Motor is in closed position.TEST PROCEDURE RESULTSA. Disconnectfactory-installedresistor fromterminals S R and +. 1. LED (light-emitting diode)should be on.2. Motor drives toward open.Table 17 — High and Low Enthalpy SimulationTEST PROCEDURE RESULTSA. Reconnect factory-installed800 ohm resistorbetween terminalsS R and +.B. Connect 1200 ohmcheckout resistorbetween terminalsS O and +.C. Turn set point potentiometerto position A. Low outdoor-air test results:1. LED (light-emitting diode)should be on.2. Motor drives toward open.D. Turn set point potentiometerto position D.E. Disconnect 1200 ohmcheckout resistor. High outdoor-air test results:1. LED should be off.2. Motor drives toward closed.20