Carrier 30XA080-500 Controls, Start-up, Operation, Service And Troubleshooting Instructions

Also see for 30XA325: Installation instructions Installation instructions

Carrier 30XA080-500 Controls, Start-up, Operation, Service And Troubleshooting Instructions Manual pdf 66 page image

Charging with Unit Off and Evacuated -- Close liquid lineservice valve before charging. Weigh in charge shown on unitnameplate. Open liquid line service valve; start unit and allowit to run several minutes fully loaded. Check for a clear sightglass. Be sure clear condition is liquid and not vapocCharging with Unit Running -- If charge is to be added whileunit is operating, all condenser fans and compressol_ must beoperating. It may be necessa U to block condenser coils at lowambient temperatures to raise condensing pressure to approxi-mately 198 psig (1365 kPa) to turn all condenser fans on. Do nottotally block a coil to do this. Partially block all coils in unif(mnpattern. Chtu_ge each circuit until sight glass shows dear liquid,and has a liquid line temperature of 103 F (39 C) for 30XA080-350 units and 108 F (42 C) for 30XA400-500 units.Add 5 lb (2.3 kg) of liquid chtu_ge into the entering filterdrier using the fitting located on the tube entering the bottom ofthe coolec This fitting is located between the electronic expan-sion valve (EXV) and the coolel:Allow the system to stabilize trod then recheck the liquidtemperature. If needed, add additional liquid charge, 5 lb(Z3 kg) at a time, allowing the system to stabilize betweeneach charge addition. Slowly add charge as the sight glassbegins to clear to avoid overcharging.IMPORTANT: When adjusting refrigerant chtuge, circu-late fluid through cooler continuously to prevent freezingand possible dmnage to the coolel: Do not overcharge, andnever charge liquid into the low-pressure side of system.Safety DeviceS--The 30XA chillers cont;fin manysafety devices and protection logic built into the electroniccontrol Following is a description of the major safeties.COMPRESSOR PROTECTIONMotor Overload -- The compressor protection modules(CPM) protect each compressor against overcurrent. Do notbypass the current transducel_ or make any changes to thefactory-installed and configured headers. The configuration ofthese headers defines the Must Trip Amps (MTA) at which theCPM will turn the compressors off. Determine the c;mse fortrouble and correct the problem before resetting the CPM. SeeAppendix C for MTA settings and configuration headers.Each CPM bo;ud also reads the status of each compressor'shigh-pressure switch. All compressors have factory-installedhigh-pressure switches. See Table 37.Table 37 -- High-pressure Switch SettingsSWITCH SETTINGUNITpsig ] kPa30XA 304.5 _+14.5 2099 _+100If the switch opens during operation, the compressor will beshut down. The CPM will reset automatic_flly when the switchcloses, however, a manual reset of the control is required torestart the compressor:OIL SEPARATOR HEATERS -- Each oil separator circuithas a heater mounted on the underside of the vessel. The heateris deenergized anytime the compressor is on. If the compressoris off and outdoor-air temperature (OAT) is greater than 100 F(37.8 C) the heater is deenergized. The heater will also bedeenergized if OAT - SST >32 F (17.8 ° C) and the OAT -LWT > 32F (17.8° C).COOLER PROTECTIONLow Water Temperature -- Microprocessor is programmedto shut the chiller down if the leaving fluid temperature dropsbelow 34 F (1.1 C) for water or more than 8 ° F (4.4 ° C) belowset point for Fluid Type = brine. When the fluid temperaturerises 6 ° F (3.3 ° C) above the leaving fluid set point, the safetyresets and the chiller restarts. Reset is automatic as long as thisis the first occurrence of the day.IMPORTANT: If unit is installed in an area whereambient temperatures fall below 32 F (0 ° C), a suit-able corrosion-inhibited antifreeze solution or coolerheater must be used in the chilled water circuit.Relief Devices -- Fusible plugs are located in each cir-cuit between the condenser and the liquid line shutoff valve.PRESSURE RELIEF VALVES -- Valves ;ue installed in eachcircuit and are located on all coolers. These valves aredesigned to relieve if an abnormal pressure condition _uises.Relief valves on _fll coolers lelieve at 220 psi (1517 kPa).These valves should not be capped. If a valve lelieves, itshould be replaced. If the valve is not replaced, it may relieveat a lower pressure, or leak due to trapped dirt from the systemwhich may prevent resealing.Plessure relief valves located on cooler shells have 3/4-in.NPT connections for lelief. Some local building codes requirethat relieved gases be exhausted to a specific location. Thisconnection _fllows conformance to this requirement.MAINTENANCERecommended Maintenance Schedule -- The fol-lowing are only recolmnended guidelines. Jobsite conditionsmay dictate that maintenance schedule is performed more oftenthan recommended.Routine:For machines with E-coat condenser coils:• Check condenser coils for debris; clean as necessary withCarrier approved coil cleaner.• Periodic clean water rinse, especially in coastal andindustrial applications.Every month:• Check condenser coils for debris; clean as necessary withCarrier approved coil cleaner.• Check moisture indicating sight glass for possible refrig-erant loss and presence of moisture.Every 3 months (for all machines):• Check refrigerant charge.• Check all refrigerant joints and valves for refrigerantleaks; repair as necessary.• Check chilled water flow switch operation.• Check all condenser fans for proper operation.• Check oil filter pressure drop.• Check oil separator heater operation.Every 12 months (for all machines):• Check all electrical connections; tighten as necessary.• Inspect all contactors and relays; replace as necessary.• Check accuracy of thermistors; replace if greater than_+2° F (1.2 ° C) variance fiom calibrated thermometer.• Check accuracy of transducers; replace if greater than_+5psi (34.47 kPa) variance.• Check to be sure that the proper concentration of anti-freeze is present in the chilled water loop, if applicable.• Verify that the chilled water loop is properly treated.• Check refrigerant filter driers for excessive pressuredrop; replace as necessary.• Check chilled water strainers, clean as necessary.• Check cooler heater operation.• Check condition of condenser fan blades and that theyare securely fastened to the motor shaft.• Perform Service Test to confirln operation of all components.• Check for excessive cooler approach (Leaving ChilledWater Temperature - Saturated Suction Temperature) whichmay indicate fouling. Clean cooler vessel if necessary.• Obtain oil analysis; change as necessmy.TROUBLESHOOTINGSee Table 38 for an abbreviated list of sylllptolllS, possiblecauses and possible remedies.66