Carrier OMNIZONE 50BV020-064 Installation And Service Instructions Manual

Also see for OMNIZONE 50BV020: Operating and troubleshooting guide

Contents

51Evaporator Fan Performance Adjustment —To change fan speeds from factory settings:1. Shut off unit power supply.2. Loosen nuts on the 4 carriage bolts in the mountingbase. Using adjusting bolts and plate, slide the motorand remove the belt.3. Loosen movable-pulley flange setscrew.4. Screw the movable flange toward the fixed flange toincrease speed, and away from the fixed flange todecrease speed. Increasing the fan speed increases theload on the motor. Do not exceed the maximum speedspecified in Tables 3A and 3B.5. Set the movable flange at nearest keyway of the pulleyhub and tighten the setscrew. (See Tables 3A and 3Bfor speed change for each full turn of pulley flange.)6. Replace and tighten the belts (see Belt Tension Adjust-ment section).7. Restore power to the unit.To align fan and motor pulleys:1. Loosen fan pulley setscrews.2. Slide fan pulley along fan shaft.3. Make angular alignment by loosening motor frommounting plate.4. Restore power to unit.BELT TENSION ADJUSTMENT — Using a gage, apply4 lb of force to the center of the belt and adjust the tension untila deflection of 1/64-in. is achieved for every inch of shaft centerdistance. See Fig. 37.Ideal belt tension is the lowest value under which belt slipwill not occur at peak load conditions.Charging the SystemREMOTE AIR-COOLED UNITS — The 50BVE,K,U,X unitsare shipped with a holding charge of dry nitrogen. Remotecondensers, interconnecting piping, and refrigerant to charge thesystem are all field supplied.To evacuate the system, refer to GTAC II, Module 4, Dehy-dration for Proper Evacuation and Dehydration Techniques.To charge the 50BVE,K,U,X systems:1. Add an initial minimum refrigerant charge after evacu-ation to allow the unit to start. Refer to Tables 25A and25B. Additional refrigerant will be added based on thelength of interconnecting piping and vertical separa-tion between the indoor unit and the condenser(s).Table 25A — Minimum Operating Charge (lb),50BVE,K Units Matched with 09DK CondensersTable 25B — Minimum Operating Charge (lb),50BVU,X Units Matched with 09DK Condensers2. To finish charging the system, make sure the unitis running at full-load operating conditions. Charge toa clear sight glass. Refer to GTAC II, Module 5,Charging, Recovery, Recycling and Reclamation andthe Refrigerant Service Techniques manual for propercharging techniques.3. Add 10 lb of R-22 or R-410A over a clear sight glassto flood subcooler section of the condenser coils.4. Alternately, and as a double-check, when properlycharged at full-load operating conditions, there shouldbe 15 F subcooling entering the TXV (the differencebetween saturated condenser temperature and actualliquid temperature entering the TXV).Compressor Oil — All units are factory charged withoil. It is not necessary to add oil unless compressor(s) is re-moved from the unit. If necessary, oil can be removed/chargedvia Schrader fitting. Operate the system at high evaporator tem-perature prior to oil recharge to assist oil return to the compres-sor(s) from other system components. If necessary, rechargethe system as shown in Table 26.Table 26 — Oil RechargeTROUBLESHOOTINGRefer to Tables 27-29 to determine the possible cause of theproblem and the associated procedure necessary to correct it.See Fig. 38-47 for unit and control wiring.UNIT SIZE 020 024 028 034Circuit 1...2 8.1...8.1 9.1...9.1 9.1...9.1 18...18UNIT SIZE 034 044 054 064Circuit 1...2 18...18 10...10 18...18 18...18Circuit 3...4 - 10...10 18...18 18...1850BVUNIT SIZE COMPRESSOROILRECHARGE(oz)OILTYPEPARTNUMBERC,E,Q,J,K020 ZR94KC 813GS 150viscosityyellowmineraloilP903-0101024 ZR108KC 106028 ZR144KC 106034 ZR19M3 137T,U,V,W,X034 ZR19M3 137044 ZR125KC 106054 ZR16M3 137064 ZR19M3 137BELT SPANLB FORCEDEFLECTIONFig. 37 — Fan Belt Tensiona50-7136efFig. 36 — Sheave Alignmenta50-7135tf