Trane WSC060-120 manual Cooling Capacity Step, Heating Capacity Step, Air Delivery Selection

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Selection Procedure - SI Units

Cooling Capacity

Step 1

Calculate the building’s total and sensible cooling loads at design conditions. Use the Trane calculation form or any other standard accepted method.

Step 2

Size the equipment using Table PD-1. Match the cooling loads at design conditions.

Example: The following are the building cooling requirements:

A

Electrical Characteristics: 380–415/50/3

B

Summer Design Conditions:

Entering Evaporator Coil: 27 DB/ 19 WB

Outdoor Ambient: 35

C

Total Cooling Load: 17.0 kW

D

Sensible Cooling Load: 11.7 kW

E

Airflow: 3,400 m3/hr

External Static Pressure: 130 Pa

F

Downflow Configuration

Table PD-1 shows that a WSC060AD has a gross cooling capacity of 18.1 kW and

14.7kW sensible capacity at 35 degree C ambient and 3,400 m3/hr with 27 DB/19 WB air entering the evaporator.

To find the net cooling capacities, fan motor heat must be subtracted. Determine the total unit static pressure:

External Static

130 Pa

Standard Filter 1 in.

37 Pa

Economizer

46 Pa

Supplementary Electric Heat

21 Pa

Total Static Pressure

234 Pa

Note: The Evaporator Fan Performance Table PD-9 has deducted the pressure drop for a 25 mm filter already in the downflow unit.

Therefore, the actualTotal Static Pressure is 234 – 37 = 197 Pa. With 3,400 m3/hr and 197 Pa,Table PD-9 shows 0.75 kW.

Note below the table gives a formula to calculate Fan Motor Heat,

Fan Motor Heat (kW) =

1.144 x (Fan kW) + 0.132

= 1.144 x 0.75 + 0.132 = 1.0 kW

NetTotal Cooling Capacity = 18.1 – 1.0 = 17.1 kW

Net Sensible Cooling Capacity = 14.7 – 1.0 = 13.7 kW

Heating Capacity

Step 1

Calculate the building heating load using theTrane calculation form or other standard accepted method.

Step 2

Size the equipment usingTable PD-5 to match the heating loads at design conditions.

A

Total Heating Load: 16 kW

B

Outdoor Ambient (Winter) –9°C DB

C

Indoor Return Temperature: 21°C DB

D

Airflow: 3,400 m3/hr

Use the portion ofTable PD-5 for the WSC060AD to determine capacity at winter design conditions. The mechanical heating portion of the heat pump will provide 8.3 kW.

Step 3

Because 8.3 kW is less than the building’s required heating capacity at winter design conditions, a supplementary heater must be selected.

16 kW – 8.3 kW = 7.7 kW

FromTable PD-9, at 380 volts, the 10.9 kW Heater will be adequate to do the job.

10.9 kW 38.0 MBh

FromTable ED-5 select heater BAYHTRR418A (10.9 kW 380/50/3).

Air Delivery Selection

External static pressure drop through the air distribution system has been calculated to be 200 Pa. EnterTable PD-9 for a WSC060AD at 3400 m3/h and 200 Pa static pressure. The standard motor will give the desired airflow.

Accessory Selection

Select accessories needed to accommodate the application.

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PKGP-PRC004-EN

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Contents Packaged Heat Pumps Introduction American Standard Inc. All rights reservedContents Features and Benefits Standardized Components Easy Access Low Voltage Terminal BoardFlexible Applications Micro Controls ReliaTel MicroEconomizer Hinged Access DoorsPhase Monitor Comm-3/4Trane Communication InterfaceWe test designs at our factory not on our customers Quality And Reliability TestingVariTrac Clearance Requirements Barometric ReliefCondensate Trap Unit PitchHeating Capacity Step Accessory SelectionCooling Capacity Step Air Delivery SelectionSelection Procedure IP Units Model Number Description 060 11 12,13General Data Table GD-1 General DataTable PD-1 Gross Cooling Capacities kW WSC060AD,T SI Performance DataTable PD-1a Gross Cooling Capacities MBH WSC060AD,T IP Table PD-2 Gross Cooling Capacities kW WSC072AD,T SI Table PD-2a Gross Cooling Capacities MBH WSC072AD,T IPTable PD-3 Gross Cooling Capacities kW WSC090AD,T SI Table PD-3a Gross Cooling Capacities MBH WSC090AD,T IPTable PD-4 Gross Cooling Capacities kW WSC120AD,T SI Table PD-4a Gross Cooling Capacities MBH WSC120AD,T IPPerformance Data At Indicated Indoor Dry Bulb Temp C Performance Data 10.4 10.8 10.0 10.410.2 10.6 10.1 10.6 11.12 HP Standard Motor Nom kW Standard Motor & Hi Static Drive2 HP Standard Motor & Static Drive Hi Static DriveDrive Nom kW Standard Motor Hi Static DriveNom kW Standard Motor 2 HP Std Motor & Drive2 HP Std Motor 2 HP Standard Motor Hi Static Drive Nom kW Standard Motor DriveNom kW Over-Sized Motor HP Over-Sized Motor & Hi Static Drive3260 1002 Nom kW Standard Motor & Drive Hi Static DriveExternal Static Pressure Pascals 275 300 325 350 375 M3/h 1920 1002HP Standard Motor Hi Static Drive Nom kW Std Motor Nom kW Standard MotorNom kW Over-Sized Motor & Hi Static Drive HP Standard MotorHP Over-Sized Motor Hi Static Drive Nom kW Standard Motor Nom kW OS2400 1051 HP Standard Motor & Low Static Drive Nom kW Standard Motor & Low Static DriveNom kW Standard Motor & High Static Drive HP Standard Motor & High Static Drive807 844 HP Std Motor & DriveTable PD-17 Standard Motor & Sheave/Fan Speed RPM Table PD-21 Sound Power Level dB ref -12WattsTable PD-20 Over-Sized Motor & Drive Sheave/Fan Speed RPM 3400 4080 3260 Econimizer withOA/RA Dampers2 4080 4890Table PD-24 Auxiliary Electric Heat Capacity Table PD-24a Auxiliary Electric Heat Capacity3400 M 3/H 4100 M 3/H 5100 M 3/H 6800 M 3/H Stages Variation From Nominal Airflow Temperature Rise MultiplierTon 10.9 11.3 12.1Controls Integrated Comfort System Sensors available342-456 Table ED-1 Unit WiringElectrical Data 180-22010.9 13.0 KW Rating380 / 415 Volts 14.4 17.2108 Volts Phase380-415 Compressor Motor Condenser Fan Motor Unit Amps Model NoWires, 24-volts, with Electric Heat Jobsite ConnectionsDimensional DataWSC060DataWSC060 DataWSC072-120 DataWSC072-120 WSC072-120 Roof Curb Accessories WSC060 Barometric Relief DamperDimensional Options WSC072-120Table W-2 Accessory Net Weights1, 2 kg WeightsTable W-2a Accessory Net Weights1, 2 lbs Mechanical Specifications Remote Potentiometer Electric HeatersRoof Curb Manual Outside Air DamperComm-5 LonTalk Communication Interface Differential Pressure SwitchesCOMM3/4Trane Communications Interface Zone SensorsPKGP-PRC004-EN PKGP-PRC004-EN Supersedes PL-UN-000-PKGP-PRC004-EN-12-03 Literature Order NumberFile Number PL-UN-000-PKGP-PRC004-EN-02-04 Stocking Location Webb/Mason 02-04 Electronic Only
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