Backdraft Barometric Relief Pressure Relief

2m ago
4 Views
0 Downloads
638.92 KB
20 Pages
Last View : 8d ago
Last Download : n/a
Upload by : Casen Newsome
Share:
Transcription

Backdraft & Pressure Relief Dampers Backdraft Barometric Relief Pressure ReliefNovember2018

Backdraft DampersBackdraft dampers (also known as gravity dampers) are used in ventilation systems to allow airflow in one directionand prevent airflow in the opposite direction. A relief damper is developed with an elevated and adjustablestart-open pressure while providing the backdraft function. When selecting the correct damper for your application,you need to know: System velocity and back pressure requirements Mounting orientation and airflow direction Mounting configuration (inserted into duct/opening or flange mounted) Damper operation (gravity or motorized) Start-open pressureMounting OrientationBackdraft dampers are available in vertical or horizontal mount.AirflowHorizontal MountAirflow UpAirflowVertical MountHorizontal MountAirflow DownFrame ConstructionThree types of frame construction are available on all commercial backdraft damper models: No flange Flange on discharge Flange on intakeDuctAirflowAirflowAirflowDuctNo Flange(Duct Insert)2Flange OnDischargeFlange OnIntake

Commercial BackdraftDampersA commercial backdraft damper is a gravity damper (when non-motorized) allowing airflow in one direction only.When placed on a propeller fan, for example, it will prevent the wind from causing the fan to run backwards whenthe power is off. When a backdraft damper is motorized, it functions like a control damper.To assist with opening the damper blades, backdraft dampers may utilize springs, adjustable counterbalanceweights, or a motorpack. Spring assist is a spring attached to the damper that helps in opening or closing the damper blades. Thespring is adjustable by using a series of holes in the frame or blade assembly to increase or decrease thetension. Adjustable counterbalance weights are a more precise means of reducing the pressure that is required toopen the damper. A motorpack is used when it is necessary that the damper opens and closes without having to rely on airvelocity or pressure.Backdraft damper selection begins by determining the damper construction required based on system velocity andstatic pressure. The BD damper series are used in applications up to 1500 ft/min (7 m/s) and 2 in. wg (0.5 kPa) ofstatic pressure. The WD, ES, GM, and SSNM damper series are used in applications up to 2500 ft/min (12.7 m/s)and 2 in. wg (0.5 kPa) of static pressure. The EM damper series are used in applications up to 3500 ft/min (17.8 m/s)and 10 in. wg (2.5 kPa) of static pressure.BD, EM, ES, GM, SSNM, and WD series dampers can be used in applications for: Exhaust Air intake Roof ventilation Sidewall ventilation In-duct ventilationBD SeriesBD series have a galvanized steel frame with aluminum blades. The dampers are opened by air pressure differentialand closed by gravity. They are rated for velocities up to 1500 fpm (7 m/s) and pressures up to 2 in. wg (0.5 kPa).These dampers have AMCA certified pressure drop and leakage performance that comply with ASHRAE 90.1 andIECC leakage requirements for non-motorized dampers.BD-100BD-300 SeriesSpringAssistedMaximumVelocityfpm (m/s)Start OpenPressure*in. wg (kPa)MaximumBack Pressurein. wg (kPa)AMCA AirLeakage & (0.002)2(0.5)YesMounting AirflowPosition D-330H HorizontalV VerticalN/A Not AvailableStd Standard*Note that start-open is the pressure at which damper blades just begin to rotate, blades are not fully open at this point.Damper size and bearing selection may cause start-open pressure to vary from this value.3

Commercial BackdraftWD SeriesThe WD series are backdraft dampers constructed of a galvanized steel frame and aluminum blades with seals. Thedampers are opened by air pressure differential (assisted by springs) and closed by gravity. When motorized, thedamper functions like a control damper. WD series dampers are rated for velocities up to 2500 ft/min (12.7 m/s) andpressures up to 2 in. wg (0.5 kPa).WD-100 SeriesWD-100 series dampers are horizontally mounted toallow vertical airflow. The primary application is with roofmounted exhaust fans. Optional motorpack is available.WD-200 SeriesWD-200 series dampers are electric motorizedbackdraft dampers that open when energized andspring return close when de-energized. Thesedampers can be used for horizontal or vertical mountapplications. The primary application is to preventundesirable reverse airflow when installed with roof orsidewall supply (intake) fans.WD-100 SeriesWD-300 SeriesWD-300 series dampers are vertical mount for horizontalexhaust applications. These dampers are designedto open easily under low velocity conditions. Optionalmotorpack is available.WD-200 SeriesWD-400 SeriesWD-400 series dampers are non-motorized and canbe mounted vertically (for horizontal intake airflow) orhorizontally (for vertical airflow down).WDR-53/SSWDR-53WDR-53 and SSWDR-53 are round backdraft dampers.These models can be mounted horizontally for verticalairflow down or up, or mounted vertically for horizontalairflow. The WDR-53 and SSWDR-53 are rated forvelocities up to 2000 ft/min (10.2 m/s) and pressureup to 3 in. wg (0.75 kPa).WDR-53/SSWDR-53End Switch KitsAn end switch kit can be used in conjunction with amotorpack. The end switch is wired to a fan and/or toa light serving as an open/closed indicator. When wiredto a fan, this will ensure the damper is fully open beforethe fan starts.End Switch Kit4

Commercial BackdraftWD SeriesMotorizedMaximumBackPressurein. wg tdOpt2500(12.7)0.01(0.002)1(0.25)WD-200NoneH or VH or VN/AStd2500(12.7)0.017(0.004)1(0.25)WD-210Motor SideH or VH or Motor SideH or VH or /A2500(12.7)0.026(0.006)2(0.5)WDR-53NoneH or VH or VStdN/A2000(10.2)0.08(0.020)3(0.75)SSWDR-53NoneH or VH or VStdN/A2000(10.2)0.08(0.020)3(0.75)V VerticalSpringAssistedStart OpenPressure*in. wg (kPa)ModelH HorizontalAirflowDirectionMaximumVelocityfpm (m/s)MountingPositionN/A Not AvailableOpt OptionalStd Standard*Note that start-open is the pressure at which damper blades just begin to rotate, blades are not fully open at this point.Damper size and bearing selection may cause start-open pressure to vary from this value.5

Commercial BackdraftEM, ES, GM & SSNM SeriesEM SeriesEM series damper have 0.070 inch (1.8mm) thick bladesand a 0.125 inch (3.2mm) thick frame made of extrudedaluminum. These dampers are rated for velocities up to3500 fpm (17.8 m/s) and pressure up to 10 in. wg (2.5 kPa).EM-30 series comply with ASHRAE 90.1 and IECC leakagerequirements for non-motorized dampers.Adjustable pressure controller is available for field settingof relief pressure. Paint is available on these models.ES SeriesES series damper have 0.050 inch (1.3mm) thick bladesand 0.063 inch (1.6mm) thick frame made of extrudedaluminum. They are rated for velocities up to 2000 fpm(10.2 m/s) and pressure up to 6 in. wg (1.5 kPa). ES-10 andES-30 series comply with ASHRAE 90.1 and IECC leakagerequirements for non-motorized dampers.EM-30 SeriesBirdscreen or insect screen is available.GM SeriesES-10 SeriesGM series damper have a galvanized steel frame withextruded aluminum blades. This series is rated forvelocities up to 2500 fpm (13 m/s) and pressure up to4 in. wg (1 kPa).SSNM SeriesSSNM series damper have 304SS blades and frame. Thesedampers are rated for velocities up to 2500 fpm (13 m/s)and pressure up to 2 in. wg (.5 kPa).EM-30 with adjustable pressure controller6ES-40 SeriesSSNM-30 Series

Commercial BackdraftEM, ES, GM & SSNM ial MaterialCounterMounting AirflowbalancePosition DirectionWeightsMaximum MaximumAMCA AirStart-OpenBackVelocityPressure* Leakage & AirPressureft/min.in. wg (kPa) Performancein. wg 3500(17.8)10(2.5)0.03 (0.007)10.01 minumOptVHorizontal2000(10.2)2.5*(0.6)0.05 (0.012)*10.015 0.2)2.5(0.6)0.075(0.019)N/AGalvanized 0.03 (0.007)10.01 (0.002)2N/A304SSN/AHVerticalUp2500(13 m/s)2(0.5)CFN/A304SSN/AVHorizontal2500(13 m/s)2(0.5)CFN/AH HorizontalV Vertical1 without weights2 with weightsN/A Not AvailableCF Consult FactoryOpt OptionalStd Standard*Note that start-open is the pressure at which damper blades just begin to rotate, blades are not fully open at this point.Damper size and bearing selection may cause start-open pressure to vary from this value.7

Heavy Duty/IndustrialBackdraft - HB & HBR SeriesHeavy duty/Industrial backdraft dampers are designed toprevent backflow at static pressures up to 20 in. wg (5 kPa)and velocities up to 6400 ft/min (32.5 m/s). Counterbalanceweights are mounted externally for easy adjustment andbalancing in the field.The HB series dampers are flange frame mounted. Widthand height dimensions are to the inside of the frame.HB and HBR series dampers can be used in applications for: Blower outlets Branch duct isolation Industrial process isolation Emergency generator radiator outletsHBR-050HBR-050 & HBR-150 Round frame and blade Corrosion resistant Optional 304 or 316 stainless steel constructionHB-110 Corrosion resistant Spark B and C resistant Optional 304 or 316 stainless steel constructionHB-110HB-120 Optional 304 or 316 stainless steel constructionHB-230 Optional 304 or 316 stainless steel constructionHB-240 Spark B and C resistant Optional Spark A resistant Optional 304 or 316 stainless steel construction (exceptblades)HB-120HB-330 Fan Class III Optional 304 or 316 stainless steel constructionHB-330Note: HB series dampers are flange frame mounted. Width and height dimensions are to the inside of the frame.8

Heavy Duty/IndustrialBackdraft - HB & HBR ocityft/min. (m/s)Maximum BackPressurein. wg (kPa)Start-OpenPressure*in. wg (kPa)0.12 (0.03)FrameBladeHBR-050Galvanized SteelGalvanized SteelStd3000 (15.2)6 (1.5)HBR-150Painted SteelPainted SteelStd4000 (20.3)6 (1.5)N/AHB-110Galvanized SteelAluminum SingleStd3900 (20)5 (1.2)0.02 (0.005)HB-120Galvanized SteelGalvanized Steel 2VStd5150 (26)8.5 (2.1)0.045 (0.11)HB-230Galvanized SteelGalvanized SteelAirfoilStd5150 (26)13.5 (3.4)0.04 (0.010)HB-240Galvanized SteelExtruded AluminumAirfoilStd5150 (26)13.5 (3.4)0.04 (0.010)HB-330Galvanized SteelGalvanized SteelAirfoilStd6400 (33)20 (5)0.25 (0.06)N/A Not ApplicableStd Standard*Note that start-open is the pressure at which damper blades just begin to rotate, blades are not fully open at this point.Damper size and bearing selection may cause start-open pressure to vary from this value.Fan AccessoryIndustrial Backdraft DampersIndustrial backdraft dampers are used on bloweroutlets for automatic isolation which allows airto pass in one direction and restrict flow in theopposite direction. Each damper is factory-adjustedfor its intended flow direction. Multiple nestedcounterbalance arms and weights are positionedto reduce load on bearings and linkage. Industrialbackdraft dampers are recommended for lowtemperatures and clean air applications.HB-230Relief DampersRelief dampers are backdraft dampers with an adjustable start-open pressure capable of maintaining a relativelyconstant pressure at various airflows and which closes upon a decrease in differential pressure. Suitable to relievebuilt up pressure in zoned duct system that could potentially cause damage to HVAC equipment.BR-40 SeriesHPR-1209

Barometric ReliefBR and SEBR SeriesA barometric relief damper is a backdraft damper with anadjustable start-open pressure. It is used for gravity ventilationand low velocity systems. Counterbalance weights provide theability to fine tune start-to-open and full-open operation.BR series dampers are constructed with a galvanized steelframe and aluminum blades. The SEBR series is constructedof 316 stainless steel for severe or corrosive environments.Vinyl blade seals are used on both series of dampers.This damper series is rated for velocities up to 2000 ft/min(10.2 m/s) and back pressure up to 2 in. wg (0.5 kPa). Thestart-open pressure is selectable from .05 to .13 in. wg(0.01 kPa to .03 kPa).BR and SEBR series dampers can be used in applications for:BR-30 Series Gravity hood intake and exhaust Stairwell pressurization Room pressurization Ductwork outletsBR-10 nAirflowDirectionBR-10NoneHVertical UpBR-11DischargeHVertical UpBR-12IntakeHVertical lAluminumVHVHVHBR-40NoneHVertical DownBR-41DischargeHVertical DownBR-42IntakeHVertical DownSEBR-10NoneHVertical UpSEBR-11DischargeHVertical UpSEBR-12IntakeHVertical UpSEBR-30NoneVHVH316 StainlessSteel316 40NoneHVertical DownSEBR-41DischargeHVertical DownSEBR-42IntakeHVertical DownH HorizontalMaximumVelocityft/min. (m/s)MaximumStart-OpenBackPressure*Pressurein. wg (kPa)in. wg (kPa)2000(10.2)2(0.5)0.05 - 0.30(0.012-0.075)2000(10.2)2(0.5)0.05 - 0.30(0.012-0.075)2000(10.2)2(0.5)0.05 - 0.30(0.012-0.075)2000(10.2)2(0.5)0.05 - 0.30(0.012-0.075)2000(10.2)2(0.5)0.05 - 0.30(0.012-0.075)2000(10.2)2(0.5)0.05 - 0.30(0.012-0.075)V Vertical*Note that start-open is the pressure at which damper blades just begin to open. The blades are not fully open at this point.Damper size and bearing selection may cause start-open pressure to vary from this value.10

Heavy Duty/IndustrialPressure Relief - HPR SeriesA pressure relief damper is a backdraft damper havingan adjustable start-open pressure that is capableof maintaining a relatively constant pressure atvarious airflows and which closes upon a decrease indifferential pressure. Pressure relief dampers do notimmediately open fully upon reaching their start-openpressure. HPR series dampers maintain tight leakageto approximately 60% of the start-open pressure andhave a relatively flat flow control, somewhat abovethe start-open pressure. Counterbalance weights aremounted externally for easy adjustment and balancingin the field. This damper series is designed to handlevelocities up to 6400 ft/min. (32.5 m/s).HPR 120HPR-120HPR series dampers can be used in applications for: Fume exhaust Duct/plenum protectionAdditional material and coating selections are availablein aluminum and stainless steel for corrosive or cleanroom applications.HPR 230HPR-230HPR-330Note: HPR series dampers are flange frame mounted. Width and height dimensions are to the inside of the ocityft/min. (m/s)MaximumBackPressurein. wg (kPa)Start-OpenPressure*in. wg (kPa)PressureReliefin. wg el 0GalvanizedSteelGalvanizedSteel R-330GalvanizedSteelGalvanizedSteel )N/A Not ApplicableStd Standard**Note that start-open is the pressure at which damper blades just begin to rotate, blades are not fully open at this point.Damper size and bearing selection may cause start-open pressure to vary from this value.11

Energy Codes &Air LeakageTwo common energy code standards that pertain to backdraft dampers are: ASHRAE Standard 90.1 - Energy Standard for Building except Low-RiseResidential Building IECC - International Energy Conservation CodeHere's the list of primary requirements for damper based on each standard:ASHRAE Standard 90.1 (2013 edition) states that maximum damper leakageat 1 in. wg for a non-motorized damper is 20 cfm/ft2. Dampers smaller than24 inches in either dimension may have leakage of 40 cfm/ft2.IECC (2015 edition) states that gravity (non-motorized) dampers shall have anair leakage rating not greater than 20 cfm/ft2 where not less than 24 inches ineither dimenson and 40 cfm/ft2 where less than 24 inches in either direction. The rate ofair leakage shall be determined at 1 inch water gauge when tested in accordance withAMCA 500D for such purpose. The dampers shall be labeled by an approved agency.Greenheck's BD, EM-30, ES-10, and ES-30 series backdraft dampers meet therequirements of ASHRAE and IECC.Air leakage is based on operation between 32 F and 120 F (0 C and 48 C).Tests for air leakage were conducted in accordance with ANSI/AMCA Standard 500-D Figure 5.7B in the intakedirection. Air performance testing conducted in accordance with ANSI/AMCA Standard 500-D, Figure 5.7BModelMaximum Leakagecfm/sq. ftPressurein. wgBD-100391Air leakage is based on operation between 32 F and 120 F (0 C and 48 C).Tests for air leakage were conducted in accordance with ANSI/AMCA Standard 500-D Figure 5.5 in the intakedirection. Air performance testing conducted in accordance with ANSI/AMCA Standard 500-D, Figure 5.5Maximum Leakage cfm/sq. ftPressurein. wgModelWidth and Height24 in. or greaterBD-300, 320, 330N/A391ES-30, 31, 327.6371EM-30, 31, 328.9351Width or heightless than 24 in.Air leakage is based on operation between 32 F and 120 F (0 C and 48 C).Tests for air leakage were conducted in accordance with ANSI/AMCA Standard 500-D Figure 5.5 in the backdraftdirection. Air performance testing conducted in accordance with ANSI/AMCA Standard 500-D, Figure 5.7BMaximum Leakage cfm/sq. ftModelWidth and Height24 in. or greaterWidth or heightless than 24 in.ES-10, 11, 127.628.9Pressurein. wg1Greenheck Fan Corporation certifies that the models BD-100, BD-300, BD-320,BD-330, ES-10, ES-11, ES-12, ES-30, ES-31, ES-32, EM-30, EM-31, and EM-32shown herein is licensed to bear the AMCA Seal. The ratings shown are based ontests and procedures performed in accordance with AMCA Publication 511 andcomply with the requirements of the AMCA Certified Ratings Program. The AMCACertified Ratings Seal applies to Air Leakage and Air Performance Ratings.12

Pressure DropBD-300 Series18 in. x 18 in.BD-10018 in. x 18 in.0.5PRESSURE DROP - INCHES WG0.20.10.050.020.20.10.050.020.010.0102x 10105x 100102x 1000010x11010x 10x 1005102x 100010FACE VELOCITY - FEET/MINUTEAMCA FIGURE 5.5FACE VELOCITY - FEET/MINUTEAMCA FIGURE 5.7BBR and SEBR Series36 in. x 36 in.EM-10 Series36 in. x 36 in.1098762.054PRESSURE DROP - INCHES WG3PRESSURE DROP - INCHES WGPRESSURE DROP - INCHES .0312x 100468102x 1000FACE VELOCITY - FEET/MINUTE312x 10345 6 7 8 9 102x 100345 6 7 8 9 1023x 100045 6 7 8 9 10FACE VELOCITY - FEET/MINUTEAMCA FIGURE 5.7B13

Pressure DropEM-30 Series24 in. x 24 in.EM-40 Series36 in. x 36 in.10865432PRESSURE DROP - INCHES WGPRESSURE DROP - INCHES WG0.50.20.11.8.6.4.2.10.08.060.05.04.020.02x 1012x 1003456789 10x 10001102x 1045 68 1023x 1004 5 6 7 8 9 102x 10004610FACE VELOCITY - FEET/MINUTEAMCA FIGURE 5.7AFACE VELOCITY - FEET/

3 Commercial Backdraft Dampers A commercial backdraft damper is a gravity damper (when non-motorized) allowing airflow in one direction only. When placed on a propeller fan, for example, it will prevent the wind from causing the fan to run backwards when