Carrier Aquasnap 30RW Installation, Operation And Maintenance Instructions

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Carrier Aquasnap 30RW Installation, Operation And Maintenance Instructions Manual pdf 16 page image

16CB20151050-5-10-10 -5 0 5 10 15504540353025D5.6 - Variable flow evaporatorVariable evaporator flow can be used in standard chillers.The chillers maintain a constant leaving water temperatureunder all flow conditions. For this to happen, the minimumflow rate must be higher than the minimum flow given inthe table of permissible flow rates and must not vary bymore than 10% per minute.If the flow rate changes more rapidly, the system shouldcontain a minimum of 6.5 litres of water per kW instead ofthe values below.5.7 - Evaporator flow rate30RW Minimumflow rate, l/sMaximum flow rate, l/s* Maximumflow rate, l/s**Single pump Dual pump020 0.3 1.7 - 1.7025 0.4 2.5 - 3.1030 0.5 2.5 - 3.1040 0.7 3.4 - 3.7045 0.8 3.8 - 4.7060 0.9 5.7 5.6 5.9070 1.2 6.2 6.1 7.3080 1.4 6.4 6.2 8.0090 1.5 6.6 6.3 8.4110 1.8 8.3 11.7 10.3120 2.2 8.5 12.4 11.4135 2.4 8.8 13.1 12.8150 2.7 9.0 13.7 14.3160 2.7 14.2 14.2 15.9185 3.1 14.5 14.5 17.0210 3.8 17.4 22.0 24.0245 4.4 17.4 22.0 24.0275 5.0 18.1 23.3 29.1300 5.5 18.1 23.3 29.1* Maximum flow rate for an available pressure of 50 kPa (unit with hydronicmodule)** Maximum flow rate for a pressure drop of 100 kPa in the plate heat exchanger(unit without hydronic module)5.8 - Condenser water flow rate (l/s)30RW Minimum flow rate*at min. condensercapacity - ∆t = 10 kNom. condenserflow rate at EuroventconditionsMaximum flow rate**at max. condensercapacity - ∆t = 5 k020 0.5 1.2 1.4025 0.7 1.5 1.8030 0.8 1.7 2.0040 1.0 2.3 2.7045 1.2 2.7 3.1060 1.4 3.3 3.8070 1.8 4.1 4.8080 2.1 4.7 5.5090 2.3 5.4 6.2110 2.8 6.4 7.4120 3.3 7.3 8.5135 3.6 8.3 9.5150 4.0 9.1 10.3160 4.2 9.4 10.9185 4.7 10.8 12.5210 5.7 12.7 14.6245 6.5 14.5 16.8275 7.3 16.6 19.0300 8.0 18.2 20.5* The minimum flow rate given is for units without hydronic module that have afixed condenser flow rate. Units with a hydronic module have a variable flowrate and no minimum fixed flow rate. The minimum flow rate is optimised byunit control in parallel with the drycooler fan stages for all operating conditions,especially at low outdoor temperature and low load conditions.** The maximum flow rate given is for units without hydronic module that havea fixed condenser flow rate. Units with a hydronic module have a variableflow rate. The maximum flow rate is optimised by unit control at all operatingconditions, based on pump capacity, system pressure losses and outdoortemperature.Notes 30RWA1 Evaporator ∆T =5 K2 Unit operation is limited by the maximum compressor condensing temperatureof 64°C.A Standard unit operation with the anti-freeze solution required and specialcontrol configuration.B Operation at high air temperature is based on the condenser selected.C Operating range down to 0°C, if the air-cooled condenser is not equipped witha variable-speed head fan.D Extended operating range with variable-speed fan.5.4 - Minimum chilled water flowIf the system water flow rate is lower than the minimumwater flow rate, recirculation of the evaporator flow mayoccur. The temperature of the mixture leaving the evaporatormust never be less than 2.8 K lower than the chilled waterentering temperature.5.5 - Maximum chilled water flowThe maximum chilled water flow is limited by the maximumpermitted pressure drop in the evaporator. It is providedin the table below. If the flow exceeds the maximum value,two solutions are possible:• Modify the flow rate with the control valve.• Bypass the evaporator to obtain a highter temperaturedifference with a lower evaporator flow rate.Condensing temperature, °C5.3 - Operating range 30RWAEvaporator leaving water temperature, °CEvaporator leaving water temperature, °CRemote condenser entering air temperature, °C60555045403530-10 -5 0 5 10 1564A