Carrier AQUAZONE 50HQP072-120 Installation And Service Instructions Manual

Contents

28For average scale deposit, allow solution to remain in con-denser overnight. For heavy scale deposit, allow 24 hours.Drain condenser and flush with clean water. Follow acid manu-facturer’s instructions.Compressor — Conduct annual amperage checks to in-sure that amp draw is no more than 10% greater than indicatedon the serial plate data.Fan Motors — All units have lubricated fan motors. Fanmotors should never be lubricated unless obvious, dry opera-tion is suspected. Periodic maintenance oiling is not recom-mended, as it will result in dirt accumulating in the excess oiland cause eventual motor failure. Conduct annual dry opera-tion check and amperage check to ensure amp draw is no morethan 10% greater than indicated on serial plate data.Belt — Check that the belt is tight. Retighten if needed. Re-place if it is split or cracked.Air Coil — The air coil must be cleaned to obtain maximumperformance. Check once a year under normal operating condi-tions and, if dirty, brush or vacuum clean. Care must be takennot to damage the aluminum fins while cleaning.Checking System Charge — Units are shipped withfull operating charge. If recharging is necessary:1. Insert thermometer bulb in insulating rubber sleeve onliquid line near filter drier. Use a digital thermometer forall temperature measurements. DO NOT use a mercuryor dial-type thermometer.2. Connect pressure gage to discharge line near compressor.3. After unit conditions have stabilized, read head pressureon discharge line gage.NOTE: Operate unit a minimum of 15 minutes beforechecking charge.4. From standard field-supplied Pressure-Temperature chartfor R-410A, find equivalent saturated condensingtemperature.5. Read liquid line temperature on thermometer; thensubtract from saturated condensing temperature. The dif-ference equals subcooling temperature.Refrigerant ChargingNOTE: Do not vent or depressurize unit refrigerant to atmo-sphere. Remove and recover refrigerant following acceptedpractices.Air Coil Fan Motor RemovalMotor power wires need to be disconnected from motorterminals before motor is removed from unit.1. Shut off unit main power supply.2. Loosen bolts on mounting bracket so that fan belt can beremoved.3. Loosen and remove the 2 motor mounting bracket boltson left side of bracket.4. Slide motor/bracket assembly to extreme right and lift outthrough space between fan scroll and side frame. Restmotor on a high platform such as a step ladder. Do notallow motor to hang by its power wires.Blower Fan Sheaves — Factory-supplied drives arepre-aligned and tensioned, however, it is recommended that thebelt tension and alignment be checked before starting the unit.Always check the drive alignment after adjusting belt tension.Sheave and belt information is shown in Table 17.Each factory-assembled fan, shaft, and drive sheave assem-bly is precision aligned and balanced. If excessive unitvibration occurs after field replacement of sheaves, the unitshould be rebalanced. To change the drive ratio, follow thesteps in the Blower Fan Performance Adjustment section.After 1 to 3 minutes of operation, check the belt tension.Also check tension frequently during the first 24 hours of oper-ation and adjust if necessary. Periodically check belt tensionthroughout the run-in period, which is normally the initial72 hours of operation.ALIGNMENT — Make sure that fan shafts and motor shaftsare parallel and level. The most common causes of misalign-ment are nonparallel shafts and improperly located sheaves.Where shafts are not parallel, belts on one side are drawn tight-er and pull more than their share of the load. As a result, thesebelts wear out faster, requiring the entire set to be replaced be-fore it has given maximum service. If misalignment is in thesheave, belts enter and leave the grooves at an angle, causingexcessive belt and sheave wear.Shaft Alignment — Check shaft alignment by measuring thedistance between the shafts at 3 or more locations. If the dis-tances are equal, then the shafts are parallel.Sheave Alignment1. To check the location of the fixed sheaves on the shafts,use a straightedge or a piece of string. If the sheaves areproperly aligned, the string will touch them at the pointsindicated by the arrows in Fig. 24. Rotate each sheave ahalf revolution to determine whether the sheave is wob-bly or the drive shaft is bent. Correct any misalignment.2. With sheaves aligned, tighten cap screws evenly andprogressively.Fig. 23 — Forced Circulation MethodSUCTIONPUMPSUPPORTTANKFINE MESHSCREENRETURNGAS VENTPUMP PRIMINGCONN. GLOBEVALVESSUPPLY1-IN.(25 mm)PIPE CONDENSERREMOVE WATERREGULATING VALVEWARNINGTo prevent personal injury, wear safety glasses and gloveswhen handling refrigerant. Do not overcharge system —this can cause compressor flooding.CAUTIONBefore attempting to remove fan motors or motor mounts,place a piece of plywood over evaporator coils to preventcoil damage.