Carrier 30RB060-390 Installation Instructions Manual

Also see for MINIMUM LOAD CONTROL ACCESSORY 30RB060-390: Installation instructions

45SYSTEM PRESSURIZATION — A proper initial cold fillpressure must be established before filling of the unit. Theinitial cold fill pressure is the pressure applied at the fillingpoint to fill a system to its highest point, plus a minimumpressure at the top of the system (4 psig minimum [27.6 kPa])to operate air vents and positively pressurize the system. Theexpansion tank is very important to system pressurization. Theexpansion tank serves several purposes:1. Provide NPSH (net positive suction head) required for thepump to operate satisfactorily.2. Set system pressure.3. Accommodate expansion or contraction of water due totemperature changes.4. Act as a pressure reference for the pump.The expansion tank pressure must be set BEFORE thesystem is filled. Follow the manufacturer’s recommendationfor instructions on setting the pressure in the expansion tank.The net positive suction head pressure required information isprovided on the pump curves in Fig. 39-51 for units with facto-ry-installed hydronic kits. See Table 6 for pump impeller sizes.Once the system is pressurized, the pressure at the connec-tion point of the expansion tank to water piping will not changeunless the water loop volume changes (either due to addition/subtraction of water or temperature expansion/contraction).The pressure at this point remains the same regardless ofwhether or not the pump is running.Since the expansion tank acts as a reference point for thepump, there cannot be two reference points (two expansiontanks) in a system, unless manifolded together. Where two ormore 30RB chillers with the hydronic option are installed inparallel, there should not be more than one expansion tank inthe system, unless manifolded together as seen in Fig. 36. It ispermissible to install the expansion tank(s) in a portion of thereturn water line that is common to all pumps, providing thatthe tank is properly sized for combined system volume.If the application involves two or more chillers in a primarysecondary system, a common place for mounting the expan-sion tank is in the chilled water return line, just before thedecoupler. See Fig. 36 for placement of expansion tank inprimary-secondary systems.If a diaphragm expansion tank is utilized (a flexiblediaphragm physically separates the water/air interface) it is notrecommended to have any air in the water loop. See the sectionon air separation on page 42 for instructions on providing airseparation equipment.FILLING THE SYSTEM(S) — The initial fill of the chilledwater or heat reclaim system must accomplish three goals:1. The entire piping system must be filled with water.2. The pressure at the top of the system must be high enoughto vent air from the system (usually 4 psig [27.6 kPa] isadequate for most vents).3. The pressure at all points in the system must be highenough to prevent flashing in the piping or cavitation inthe pump.The pressure created by an operating pump affects systempressure at all points except one — the connection of theexpansion tank to the system. This is the only location in thesystem where pump operation will not give erroneous pressureindications during the fill. Therefore, the best location to installthe fill connection is close to the expansion tank. An air ventshould be installed close by to help eliminate air that entersduring the fill procedure.When filling the system, ensure the following:1. Remove temporary bypass piping and cleaning/flushingequipment.2. Check to make sure all drain plugs are installed.Table 6 — Pump Impeller Sizes*Option Code refers to the Hydronics Option (position 11) in the model number. See Fig. 1 foroption identification.NOTE: Pump Selections are chiller size dependent. For example, dual pump “C” on a 30RB170chiller is not the same as dual pump “C” on a 30RB130 chiller.UNIT30RBPUMPHpSINGLE PUMP DUAL PUMPOptionCode * Rpm Impeller Dia.(in.)PumpCurveOptionCode * Rpm Impeller Dia.(in.)PumpCurve0600703 0,F 1750 6.5 I 6,M 1750 6.5 V5 1,G 1750 7.3 I 7,N 1750 7.3 V7.5 2,H 1750 8.15 I 8,P 1750 8.15 V9,T 3450 5.25 VI10 3,J 3450 5.4 II B,Q 3450 5.4 VI0800901005 1,G 1750 7.3 I 7,N 1750 7.3 V7.5 2,H 1750 8.15 I 8,P 1750 8.15 V10 3,J 3450 5.4 II B,Q 3450 5.4 VIIA15 4,K 3450 6.1 II C,R 3450 6.0 VIIC1101201305 1,G 1750 7.3 I 7,N 1750 7.3 V7.5 2,H 1750 8.15 I 8,P 1750 8.15 V10 3,J 3450 5.4 II B,Q 3450 5.4 VIIA15 4,K 3450 6.1 II C,R 3450 6.0 VIIC1501601701905 1,G 1750 6.5 IIIA — — — —7.5 2,H 1750 7.4 IIIB 9,T 3450 5.0 VIIB10 3,J 3450 4.6 IVA B,Q 3450 4.6 VIIIA15 4,K 3450 5.2 IVB C,R 3450 5.2 VIIIB