Transcription
AppendixIssue DateSeptember 18, 2003Appendix B: VAV ControllerFlow Calculation ConstantsVAV Controller Flow Calculation Constants.2Introduction. 2Key Concepts. 3About Flow Calculation Constants . 3Carnes Company . 4Environmental Technologies, Inc. (ETI) . 5Metal Industries. 6Nailor Industries, Inc. . 7E.H. Price, Ltd. (Winnipeg, Canada) . 9TITUS. 10The Trane Company . 12 2003 Johnson Controls, Inc.Code No. LIT-6375185www.johnsoncontrols.com
2Appendix B: VAV Controller Flow Calculation ConstantsVAV Controller FlowCalculation ConstantsIntroductionThis section provides flow calculation constants for some commonlyused box manufacturers.
Appendix B: VAV Controller Flow Calculation ConstantsKey ConceptsAbout Flow Calculation ConstantsA flow calculation constant is referred to as the flow multiplier inVariable Air Volume (VAV) controller applications created withHVAC PRO software. Other common terms for this constant areK-constant or pickup gain.The following is the standard equation for calculating flow:Flow Area 4005 PVelocityPickupGainRearranging the previous equation allows calculation of the flowmultiplier (pickup gain):2 Area 4005 PVelocityPickup Gain Flow Flow is in cubic feet per minute (cfm).Area is in square feet.4005 is a constant specific to this equation.PVelocity is in inches water column (w.c.).For more information on the flow multiplier, see the VAV SystemOperation Theory section of the VAV Terminal Control ApplicationsApplication Note (LIT-6375120).The VAV box flow calculation constants in this document representconstants used by some common box manufacturers.Note:These constants are subject to change without notice due tothe manufacturers’ design changes. Contact the specific manufacturerif you require any other information relative to accuracy.Note:Flow constants are based on laboratory data. Actual jobsitecfm readings may differ due to the accuracy of the balancer’s flowmeasurement equipment and due to turbulence and leakage.3
4Appendix B: VAV Controller Flow Calculation ConstantsCarnes CompanyDamper characteristics include: 90 travel clockwise rotation to close 3/8 in. round shaftTable 1: Carnes Company Box InformationBox TypeModel NumberStandard Sensor--Cross-Flow Sensor--Table 2: Carnes Company Standard Sensor ConstantsConstantsKInlet Size(in.)cfm @1 in. w.c.Area(sq 371.89 x 1219800.7502.316 x 1852001.8752.116 x 2464752.502.4Table 3: Carnes Company Cross-Flow Sensor ConstantsConstantsKInlet Size(in.)cfm @1 in. w.c.Area(sq 372.29 x 1219300.7502.416 x 1854501.8751.916 x 2474002.501.8
Appendix B: VAV Controller Flow Calculation ConstantsEnvironmental Technologies, Inc. (ETI)Damper characteristics include: round butterfly dampers 90 damper stroke clockwise rotation to close 1/2 in. round shaft full open and full close damper stopsTable 4: ETI Box InformationBox TypeModel Number--SDR--CFR--VFRTable 5: ETI ConstantsConstantsKInlet Size(in.)cfm @1 in. w.c.Area(sq 2287603.562.6425
6Appendix B: VAV Controller Flow Calculation ConstantsMetal IndustriesDamper characteristics include: 90 travel either direction to close 3/8 in. square shaftTable 6: Metal Industries Box InformationBox TypeModel NumberSingle Duct(Cooling Only)With: Electric Reheat-- HW Reheat-- Special Pickups-- Retro Kits--Constant to VAV(6-8-10) Square Retros--Dual Duct--Fan Induction--Bypass--Table 7: Metal Industries ConstantsInlet Size(in.)cfm @1 in. w.c.High Gain Unit*cfm @ 1 in. w.c.ConstantsAreaK(sq 25000.791.601432501.071.741644001.401.6218 x 1662002.001.67520 (20 x 16)62002.222.06524 (24 x 16)72002.672.20*High Gain Unit is available at no charge.
Appendix B: VAV Controller Flow Calculation ConstantsNailor Industries, Inc.Damper characteristics include: 90 travel (retrofit units) or 45 travel (single duct, dual duct, andfan powered units) counterclockwise rotation to open 1/2 in. shaftTable 8: Nailor Industries, Inc. Box InformationBox TypeModel NumberRetrofit Terminal UnitRoundSquare or Rectangular36 VRR36 VRSSingle Duct Terminal Unit3000 SeriesDual Duct Terminal Unit3200 SeriesSeries Fan Power Terminal Unit35S35SSTParallel Fan Power Terminal Unit35PTable 9: Nailor Industries, Inc. Constants for Retrofit Terminal UnitsRound UnitsUnit Size (in.)K ConstantSquare or Rectangular UnitsUnit (Port) SizeK 2152.08161.94162.14----172.14----182.11----192.067
8Appendix B: VAV Controller Flow Calculation ConstantsTable 10: Nailor Industries, Inc. Constants for Single Duct and DualDuct Terminal UnitsConstantsKInlet Size (in.)Area (sq 52.0380.3382441.7690.4296011.77100.5318662.2412 (oval)0.73811.7514 (oval)0.9510451.8716 (oval)1.163991.6524 x 162.6320532.00Table 11: Nailor Industries, Inc. Constants for Series and Parallel FanPower Terminal UnitsConstantsKInlet Size (in.)Area (sq 1232.11141.0500122.0216 (oval)1.163991.9418 (oval)1.6936042.11
Appendix B: VAV Controller Flow Calculation ConstantsE.H. Price, Ltd. (Winnipeg, Canada)Damper characteristics include: 90 travel counterclockwise rotation to close 1/2 in. round shaftTable 12: E.H. Price, Ltd. Box InformationBox TypeModel NumberSingle Duct(Cooling Only)SDV5000/8000Fan Powered Terminal UnitsSeries Fan(Constant Volume)FDC5000/8000Parallel FanFDV5000/8000Dual Duct*DDS5000/8000DDQ5000/8000*Different constants are provided for dual duct downstream (total flow) sensorsand inlet sensors.Table 13: E.H. Price, Ltd. Constants for Single Duct, Fan Powered, andDual Duct Inlet BoxesConstantsKInlet Size(in.)cfm @1 in. w.c.Area(sq 2100.7852.031430501.0691.971640101.3961.9424 x 1680002.6671.789
10Appendix B: VAV Controller Flow Calculation ConstantsTable 14: E.H. Price, Ltd. Constants for Dual Duct Downstream (TotalFlow) BoxesConstantsKInlet Size(in.)cfm @1 in. w.c.Area(sq per characteristics for all units include: 90 travel counterclockwise rotation to close 1/2 in. diameter damper shaftTable 15: TITUS Box InformationBox TypeSingle Duct(Cooling Only)Fan-Powered Terminal UnitsSeries Fan(Constant Volume)Parallel Fans(Variable Volume)Dual Duct Terminal UnitsModel NumberDESVDECVDTFCDTQSDFCLDMFVDTQPDFVLDEDVDEDCDMDV
Appendix B: VAV Controller Flow Calculation ConstantsTable 16: TITUS Constants for Inlet Sensor Applications *ConstantsKInlet Size(in.)cfm @1 in. w.c.Area(sq 22*Includes all units except Quiet Constant Volume (QCV) retrofit units.Table 17: TITUS Constants for Discharge Sensor Dual DuctApplicationsConstantsKInlet Size(in.)cfm @1 in. w.c.Area(sq 6191.0032.351438081.4012.171648101.681.9611
12Appendix B: VAV Controller Flow Calculation ConstantsThe Trane CompanyThe Trane Company boxes contain an internal actuator. Whenordering, select part number AP-VMA1430, which is a controllerwithout an actuator.Table 18: The Trane Company Constants – D and E Style Air ValveControls Group507 E. Michigan StreetP.O. Box 423Milwaukee, WI 53201BoxInlet Size(in.)cfm @1 in. w.c.ConstantsAreaK(sq shed in U.S.A.
Appendix B: VAV Controller Flow Calculation Constants 5 Environmental Technologies, Inc. (ETI) Damper characteristics include: round butterfly dampers 90 damper stroke clockwise rotation to close 1/2 in. round shaft full open and full close damper stops Table 4: ETI Box Information Box Type Model Number -- SDR-- CFR
