Carrier AQUAZONE 50PCH Installation And Service Instructions Manual

Also see for AQUAZONE 50PCH: Installation, Start-Up and Service Instructions Installation and service instructions Installation, Start-Up and Service Instructions

39Air Coil Cleaning — Remove dirt and debris from evap-orator coil as required by condition of the coil. A 10% solutionof dishwasher detergent and water is recommended forcleaning both sides of the coil, followed by a thorough waterrinse. Clean coil with a stiff brush, vacuum cleaner, or com-pressed air. Use a fin comb of the correct tooth spacing whenstraightening mashed or bent coil fins.Condenser Cleaning — Water-cooled condensers mayrequire cleaning of scale (water deposits) due to improperlymaintained closed-loop water systems. Sludge build-up mayneed to be cleaned in an open water tower system due toinduced contaminants.Local water conditions may cause excessive fouling orpitting of tubes. Condenser tubes should therefore be cleaned atleast once a year, or more often if the water is contaminated.Proper water treatment can minimize tube fouling andpitting. If such conditions are anticipated, water treatmentanalysis is recommended. Refer to the Carrier System DesignManual, Part 5, for general water conditioning information.Clean condensers with an inhibited hydrochloric acidsolution. The acid can stain hands and clothing, damageconcrete, and, without inhibitor, damage steel. Cover sur-roundings to guard against splashing. Vapors from vent pipeare not harmful, but take care to prevent liquid from beingcarried over by the gases.Warm solution acts faster, but cold solution is just as effec-tive if applied for a longer period.GRAVITY FLOW METHOD — Do not add solution fasterthan vent can exhaust the generated gases.When condenser is full, allow solution to remain overnight,then drain condenser and flush with clean water. Follow acidmanufacturer’s instructions. See Fig. 30.FORCED CIRCULATION METHOD — Fully open ventpipe when filling condenser. The vent may be closed whencondenser is full and pump is operating. See Fig. 31.Regulate flow to condenser with a supply line valve. Ifpump is a nonoverloading type, the valve may be fully closedwhile pump is running.For average scale deposit, allow solution to remain incondenser overnight. For heavy scale deposit, allow 24 hours.Drain condenser and flush with clean water. Follow acid manu-facturer’s instructions.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-Temperaturechart for R-410A, find equivalent saturated condens-ing temperature.5. Read liquid line temperature on thermometer; thensubtract from saturated condensing temperature. The dif-ference equals subcooling temperature.6. Compare the subcooling temperature with the normaltemperature listed in Tables 15-25. If the measured liquidline temperature does not agree with the required liquidline temperature, ADD refrigerant to raise the tempera-ture or REMOVE refrigerant (using standard practices) tolower the temperature (allow a tolerance of ± 3° F).Refrigerant ChargingNOTE: Do not vent or depressurize unit refrigerant toatmosphere. Remove and recover refrigerant followingaccepted practices.CAUTIONFollow all safety codes. Wear safety glasses and rubbergloves when using inhibited hydrochloric acid solution.Observe and follow acid manufacturer’s instructions.Fig. 30 — Gravity Flow MethodFILL CONDENSER WITHCLEANING SOLUTION. DONOT ADD SOLUTIONMORE RAPIDLY THANVENT CAN EXHAUSTGASES CAUSED BYCHEMICAL ACTION.PAILFUNNELCONDENSERPAIL3’ TO 4’VENTPIPE 5’ APPROX1”PIPEa50-6286efWARNINGTo prevent personal injury, wear safety glasses and gloveswhen handling refrigerant. Do not overcharge system —this can cause compressor flooding.SUCTIONPUMPSUPPORTTANKFINE MESHSCREENRETURNGAS VENTPUMP PRIMINGCONN. GLOBEVALVESSUPPLY1” PIPECONDENSERREMOVE WATERREGULATING VALVEFig. 31 — Forced Circulation Methoda50-6287ef