Control Damper Training Manual
Training Manual - Air Control Products Control Dampers
Manual Balancing Dampers Commercial Control Dampers Industrial Control Dampers Application
Control Dampers are an integral part of every Heat Ventilation Air Conditioning system. Their blades are manually or automatically set in a specific position to regulate airflow and thus control:
• Volume • Temperature • Pressure
• Installed vertically, horizontally, and even at an angle. • Field attachment & mounting are typically the responsibility of the installer- dependent upon the job conditions. Volume Control Dampers
Typically installed as one of the following:
• Fan Inlet/Outlet Dampers Used to control air flow rate to or from the fan.
• Balancing Dampers Limit flow down the duct or through a device- holds blades at a specific and fixed position.
• Branch Dampers Regulates air flow rate at a branch in the duct .
Typical Branch Damper Application Temperature Control Dampers
Typically installed in pairs or as several dampers working together & installed as:
Mixing Dampers • Operate together to maintain a specific temperature by mixing air from different sources having different temperatures. • Able to control air temperature and volume
Basic Mixing Application Temperature Control Dampers
Face & Bypass/Multi-Zone Dampers • Regulates face air in unit (hot or cold) with bypass/return air to maintain temperature. • Arranged side-by-side, top-bottom, or at right angles.
Typical Face & Bypass Application System Type/Rating
Dampers must maintain their structural & operational capabilities in the HVAC system into which they are installed. That means they must withstand the pressures, velocities, and temperatures of the installation.
As a rule of thumb systems can be rated as being Low, Medium or High Pressure as follows:
System System System Class Velocity (fpm) Pressure (in.wg.) Low Up to 1500 Up to 2.0 Medium >1500 to 3000 Up to 5.0 High >3000 to 6000 Up to 10.0
Note: The higher of the two, System Velocity or System Pressure dictates the system class. Testing
Dampers are tested & rated to qualify their performance and reliability so as to ensure that they function as expected in the HVAC system.
The most common tests are:
1. Air Performance- Pressure Drop Defined as the pressure drop across the damper for a given air flow rate through the face area of the damper expressed (plotted) as the measured pressure drop versus the velocity through the damper face for a given damper size.
Note: The plot is only applicable for Typical Pressure the size tested. Drop Curve Testing
Pressure drop testing is usually conducted in accordance with AMCA 500-D, Laboratory Methods of Testing Dampers. The tests are normally conducted on one or more of the following setups:
Ducted Inlet & Outlet - AMCA 5.3 Ducted Inlet Only - AMCA 5.2 Plenum Mount - AMCA 5.5
AMCA 5.3 – Ducted Inlet & Outlet AMCA 5.5 – AMCA 5.2 Plenum Mount Ducted Inlet
When tested in the above setups, the resulting pressure drop will be the lowest in AMCA 5.3 and the highest in AMCA 5.5. Testing
Subsequent to the pressure drop testing to AMCA 500-D, the dampers can be AMCA Certified for their Air Performance in accordance with AMCA 511, Certified Rating Program (CRP) for Air Control Devices.
To meet the requirements, five sizes of dampers must be tested: (12" x 12", 24" x 24", 36" x 36", 12" x 48" & 48" x 12") and their pressure drop curves must be published.
The purpose of the AMCA CRP is to give the buyer, specifier, and user assurance that published ratings for air control devices are reliable and accurate. At the same time the CRP program assures manufacturers that competitive ratings are based on standard test methods and procedures and are subject to check by an impartial authority. Testing
Sealing Performance- Air Leakage Defined as the airflow leakage rate through the damper for a given pressure differential across the damper- is expressed (plotted) as the volume of air through the damper, per square area of damper at a specific pressure drop, in the closed position.
Air Leakage testing is usually conducted in accordance with AMCA 500-D, Laboratory Methods of Testing Dampers. Testing
Subsequent to the leakage testing to AMCA500-D, the dampers can be AMCA Certified for their Air Leakage in accordance with AMCA 511- Certified Rating Program (CRP) for Air Control Devices. To meet the requirements, the following sizes must be tested: - 12" wide x 48" high - max. width x 36" high and the leakage class must be published.
AMCA has defined leakage classes in accordance with the following values: Maximum Allowed Leakage (cfm/ft2) Class @ 1 in.wg. @ 4 in.wg. 1A 3 8 1 4 8 2 10 20 3 40 80 Damper Construction Control Dampers have different designs based on their components and are constructed from a variety of frames, blades, axles, bearings, blade linkage and other parts to suit the particular application for that damper.
Jamb Seal Top Frame
Jamb Blade Seal (Frame) Jackshaft Linkage Bar Bracket
Jackshaft Knee Lock Bottom Frame Axle Blade Stop Frames
Dampers installed in ducts have frames categorized as Hat Channel, ‘U’ Channel, or Flat. Their outside dimensions (O.D.) are typically 1/8" to 1/4" smaller than that of the duct.
Dampers that match up or mate to ducts have a Flanged frame. Their inside dimension (I.D.) is typically the same size as that of the duct.
Hat “U” Flat Flanged Blades
Typically categorized as:
• Flat for single-bladed dampers in low pressure applications.
• Triple-V for low to medium pressure applications.
• Airfoil for medium to high pressure applications. Blade Axles Damper Shaft attached to the damper blade that Frame extends through the damper frame to Blade Axle Bearing - permit rotation of the blades. Sleeve Type • Various shapes (round, square, hex), sizes (1/4" to 1"), lengths, & materials (plated steel, stainless steel). Blade Axle Bearings Press-fit into or rotate in an extruded hole Extruded Hole in the jamb frame to permit easy rotating of the damper blade & shaft. • Various types (sleeve, ball-bearing), sizes, and materials (synthetic, stainless steel oilite, bronze). Blade Stops Metal strips attached to the inside top & bottom damper frame- provide a positive stop for the damper blades when fully closed. They help to limit leakage between the closed blade and the stop. Note: Not all damper designs have blade stops. Blade Linkage Mechanism that connects the blades together and permits them to operate in sequence. There are two types:
• Concealed - in the damper frame and does not affect the pressure drop.
• Exposed – mounted on the face of the damper blades, is in the air stream and typically increases the pressure drop.
Concealed Exposed Linkage Linkage Blade Action
Parallel • All blades rotate together in the same direction. • Typically two-position control.
Opposed • Adjacent blades rotate in opposite directions. • Balancing and modulating control.
Parallel Opposed Damper Drive Mechanism
Mechanism that operates all the blades together through a single Drive Blade- either one of the following:
• Direct Drive - a shaft extending from one side of the damper. (Typically 3/8" square or 1/2" round).
• Jack Shaft - a shaft, offset but connected to the drive blade, extending past the side of the damper- Direct Drive required when connecting multiple single-sectioned dampers together. (Typically 1/2" or 3/4" round).
Jack Shaft Low Leakage Seals
Where it is required to restrict the flow of air through a damper in the closed position, it is usually equipped with low leakage seals.
Jamb Seals – typically a flexible metal strip positioned between the end of the blades and the inside of the damper frame, running the full height of the frame. When the blades are fully closed, it restricts the flow of air between the ends of the blades and inside of the damper frame.
Blade
Jamb Seal Frame
Front View Section View -Blades Closed Low Leakage Seals
Blade seals – typically a flexible rubber, metal or synthetic seal attached to the edge of the damper blades so as to restrict the flow of air between adjacent blades and between the blade edges and the blade stops, when the blades are fully-closed.
Blade-To-Blade Overlap Blade-To-Stop Sleeves
Control dampers are supplied for field mounting in one of the following three ways:
1. No-Sleeve Side Plate • For installation in an existing duct or opening • Supplied 1/4" under nominal (ordered) size
2. Side Plate • For installation in an existing duct where the installer cuts a slot in the duct (approx. the same width as the damper frame depth) & slides the damper into the duct. Damper with • Supplied 1/4" under nominal (ordered) size Side Plate • Our std. side plate is 12" wide x 16 gauge Sleeves
3. Sleeve • For installation to connect to existing duct(s) • Sleeve O.D. is close to same size as ordered. - 20 gauge sleeve = 1/8" under nominal (ordered) size & the thicker the sleeve the closer the O.D. is to nominal size • Optional Transitions: AR (round), AO (oval), AF (Flange) can be ordered
• Sleeve advantage- Labor Saver - Ready to install from factory
Damper with Sleeve Material Construction
Control Dampers are typically constructed from one of the following materials:
• Galvanized Steel
• Stainless Steel – normally type 304 but in some rare cases, type 316.
• Aluminum
In most cases all of the major damper components are made from the same material. Damper Types
Dependent upon system velocity and pressure, control dampers can be categorized as one of the following types:
Manual Commercial Industrial Balancing Control Manual Balancing Dampers
• Damper (blades) typically controlled (locked in place) using a manual locking.
• NOT meant for full closure/low leakage applications.
• Used in low, medium and high pressure & velocity systems. Manual Balancing Dampers
Flat (Single) Blade – for “light-duty” applications. For systems having a maximum 1500 fpm and 1" wg. -
• Model CD-10 for square and rectangular applications.
CD-10 • Model CD-10R for round duct.
Both of the above are field controlled by locking the factory supplied manual locking quadrant that is attached directly to the damper frame.
CD-10R Manual Balancing Dampers
In certain applications it may be required to control the damper blade setting from a remote location.
For these applications we equip our dampers with our Remote Control Cable Assembly on the following models:
• Model RCS-10 for square and rectangular applications. RCS-10 • Model RCS-10R for round duct.
The above dampers are identical in construction to our CD-10 and CD-10R dampers except they have the factory attached remote control cable assembly. The assembly is adjusted using a hex shaped tool. RCS-10R Manual Balancing Dampers
In certain applications it may be required to control the damper blade setting from a cable located in the ductwork.
For these applications we offer a radial blade damper with a cable that can be easily adjusted and stored inside the a square or slot diffuser
• Model RCS-15R for round duct.
RCS-15R The RCS-15R is designed to be easily installed in round duct to allow adjustment at the face of the diffuser. This eliminates the need to mount a control cable in the ceiling outside the ductwork. Manual Balancing Dampers
Triple-V Blade – for square/rectangular applications
For systems having a maximum 2000 fpm and 5" wg. - • Model MD-41 for parallel bladed requirements.
• Model MD-42 for opposed bladed requirements. MD-42 The above have no top or bottom stops as they are not meant for positive closure applications.
When required to be remotely controlled - • Model RCS-42 - opposed bladed only. RCS-42 Manual Balancing Dampers In certain applications it may be required to control the damper blade setting from a remote location.
For these applications, we equip our dampers with our Handheld Remote Damper Controller on the following models:
• RD-10 – for hard ceiling square/rectangular RD-10 applications where access to adjust damper is difficult.
• RD-10R – for hard ceiling round applications where access to adjust damper is difficult.
Dampers are powered by a 9 volt DC actuator with RJ-11 6P4C connection, powered by optional RC-9V handheld remote damper controller. RD-10R Automatic Balancing Dampers
In certain applications it may be beneficial to use an automatic balancing damper to control air volume
For these applications we offer a constant airflow regulator that can be field adjusted to supply a set volume of air
• Model CAR for round duct.
The CAR is designed to be easily installed in round duct to supply a constant volume of air at a field preset CAR CFM. The CAR can be adjusted using a T-30 TORX star bit during installation and is available in standard, low, and high pressure ranges. Automatic Balancing Dampers
Models CAR-T and CAR-FD are assemblies utilizing Automatic Balancing Dampers
Model CAR-T with Square to Round transition.
Model CAR-FD with optional Fire Damper. Commercial Control Dampers
• Most common type of Control Damper
• Damper (blades) controlled using an electric or pneumatic actuator – a manual locking quadrant can be used also.
• Used in low, medium and high pressure & velocity systems Commercial Control Dampers
True Round – easiest installation to round duct.
For systems having a maximum 1500 fpm - • Model CD-21R, single-V blade design- limited to a maximum system pressure of 1" wg • Model CD-22R, opposed triple-V CD-22R blade design- limited to a max. system pressure of 2.5" wg
For systems having a maximum 4000 fpm, & 4.0 to 10.0 wg. - • Model CD-25R, single 14 ga. equivalent blade, low leakage design CD-25R Commercial Control Dampers Square/Rectangular – blade profile (shape) dictates capability to meet system velocity & pressure requirements. – all models are manufactured in a very similar design.
For systems with maximum 2000-3000 fpm & 2.5"-5.0" wg. - • Model CD-41, parallel triple-V blade design. • Model CD-42, opposed triple-V blade design. Both models have been air performance tested and are certified by AMCA.
For systems with maximum 3000-4000 fpm & 6.0"-9.0" wg. - • Model CD-45, parallel airfoil blade design. • Model CD-46, opposed airfoil blade design. Both models have been air performance tested and are certified by AMCA for pressure drop performance and Class 1 and 1A Leakage . CD-42 Commercial Control Dampers
For systems with maximum 3000-6000 fpm & 3.1" -10.0" wg., we offer: • Model CD-51, parallel airfoil blade design. • Model CD-52, opposed airfoil blade design. Both models have been air performance tested but are not certified by AMCA.
For systems requiring insulated dampers we offer: • Model TICD-51/-BF/-BFX • Model TICD-52/-BF/-BFX
For applications requiring dampers having an overall depth less than those shown previously and for systems with maximum 3000-6000 fpm & 3.1"-10.0" wg. CD-52 • Model CD-53, parallel airfoil blade design. • Model CD-54, opposed airfoil blade design. Commercial Control Dampers
All of our square/rectangular commercial control dampers can be supplied as Face and By-Pass Assemblies as below: Mixing Dampers Certain applications require dampers to work sequentially so air in different ducts, with different temperatures, can be mixed together.
For systems with maximum 2000-3000 fpm & 2.5"- 5.0" wg., - • Model MX-30 - ducts installed on top of each other - top fully closed when bottom is fully open and vice versa.
• Model MX-32 - ducts installed side-by-side - left fully closed when right is fully open and vice versa.
• Model MX-40 - multiple two-duct systems installed on top of each other other - top closed when bottom is open and vice versa.
MX-30 MX-32 MX-40 Industrial Control Dampers
• Used when temperature, pressure or velocity exceeds commercial damper limitations.
• Typically are flanged frame- mounted directly to duct or fan housing. Supplied approx. net I.D.
• Controlled by a manual locking quadrant or by an electric or pneumatic actuator. Actuators are external mount only.
• Actuators are normally, but not always more powerful (greater torque) than those used for Commercial Control Dampers.
Used in medium and high pressure & velocity systems. Industrial Control Dampers
The following outlines our Industrial Control Dampers after which there is a table detailing the standard construction of each model.
True Round – for systems with max. velocity 4000-6000 fpm and max. pressures 6.5" to 10.0" wg.
• Model CD-81R single blade design with continuous blade axle- full diameter of damper.
Continuous Blade Axle CD-81R
Frame depth & thickness vary with damper diameter as do the blade thickness and blade axle diameter. Industrial Control Dampers
Model CD-95R - Bubble Tight Damper
For systems with maximum 30 in. wg. and 6500 fpm
§ Ideal for government industrial processing plants, laboratories, clean rooms, pharmaceutical facilities, nuclear facilities, DOE facilities, and other applications that require extremely low leakage
§ Zero leakage up to 30 in. wg. of differential pressure
§ 100% in process inspection Industrial Control Dampers
Square/Rectangular Channel Frame Concealed Linkage – frame & blade thickness and blade axle diameter dictates capability to meet system requirements – thicker material, larger axle diameter for higher velocity & pressures.
– all models are manufactured similar & all are triple-V blades.
CD-81
For systems with maximum 2000-3000 fpm & 3.0" -10.0" wg. • Model CD-81, parallel blade & • Model CD-82, opposed blade. Industrial Control Dampers
For systems with maximum 4000-5000 fpm & 6.0" -15.0" wg., - • Model CD-83 parallel blade design. • Model CD-84 opposed blade design.
For systems with maximum 4000-6000 fpm & 7.0" -20.0" wg., - • Model CD-85 parallel blade design. • Model CD-86 opposed blade design. CD-84 Industrial Control Dampers For systems with maximum 3000-4000 fpm & 4.5" -9.0" wg. § Double skin airfoil blades and a rugged flanged frame for automatic air control and manual balancing in medium to high pressure applications
• Model CD-91, parallel blade & • Model CD-92, opposed blade.
For systems with maximum 4000-5000 fpm & 12.0" -32.0" wg. CD-92 § Double skin airfoil blades and a rugged flanged frame and options for ultra-low leakage in high temperature air and high pressure applications that make it ideal for high performance air intake and discharge applications where ultra-low leakage is critical.
• Model CD-93, parallel blade & • Model CD-94, opposed blade. Industrial Control Dampers
For systems with maximum 4000 fpm & 17.0" -32.0" wg.
§ Engineered and qualified for use in transit tunnel systems where tight shutoff at high velocity and/or pressure is required.
§ Meet the demanding requirements for strength, leakage and operability in accordance with NFPA-130, NFPA-502, and UL-555S.
TD-93 • Model TD-93, parallel blade & • Model TD-94, opposed blade. Blast Suppression Dampers
Model BC-550
For systems with maximum 4000 fpm
§ Ideal for government buildings, mining, oil and gas, or refineries where protection of HVAC systems is required.
§ Engineered and qualified to withstand 15psi of blast pressure.
§ Covers several Unified Facilities Criteria (UFC) and General Services Administration (GSA) codes. Actuators
Control damper blades are typically held in position using one of the following Locking Quadrant types of actuators:
• Manual locking quadrant
• Electric actuator: Power supply- 24, 120, or 230 volts. Operation- Spring Return (damper returns to original position when power is turned off) Power open/Power Close. Operating Mode- 2-Position (damper is open or closed) Modulating (damper position is set by modulating signal). Floating (damper can be held in any Belimo AF-120 position between full open & closed). Electric Actuator Actuators
Actuators for control dampers are typically mounted internally or externally.
External mount actuators typically Require a side plate or a sleeve to mount the actuator. External Mount
Internal mount actuators normally require that the damper has offset jack shafting.
Internal Mount Actuators • Pneumatic actuator: Power supply- 20 psi. Operation- Spring Return (damper returns to original position when power is turned off). Operating Mode- 2-Position (damper is open or closed) Modulating (damper position is set by modulating pressure signal).
Siemens 331-4826 Pneumatic Actuator
Electric & pneumatic actuators control the position of the damper based on signals from the Building Automation System (BAS), Thermostats & Controllers, Pressure Switches and Relays. Actuators Switches for actuators: 2-position control.
Parallel Actuators Switches for actuators: Modulating.
SGA 24
Opposed Actuator Enclosures Our electric actuators can be supplied with a variety of enclosures to supply necessary protection under certain field installations. Following is a list of those available:
• ZS-100 Weather Shield, for moderate protection to actuators mounted outdoors- NOT designed for a water tight enclosure.
• ZS-260 Explosion-proof Housing, for UL approved applications: ZS-100 • Class I, Division 1 & 2,Groups B, C, D, (NEMA 7) • Class II, Division 1 & 2, Groups E, F, G, (NEMA 9) • Class III, Hazardous locations, outdoor application NEMA 4.
ZS-260 Actuator Enclosures • ZS-300 Protective Housing, conforms to NEMA standard for Type 4X.
Intended for use primarily to provide protection against corrosion, windblown dust and rain, splashing water, hose- directed water undamaged by the formation of ice on the enclosure. The enclosure resists moisture, dust, salt and corrosive chemicals.
ZS-300 Blade Position Indicators In some circumstances it is required that the position of the blades is monitored. This is accomplished using a micro switch mechanism attached to our damper and typically connected (electrically) to a light to indicate when the damper blades are fully open or fully closed.
Following are two options for this application:
1. PI-50, in-house assembled package, directly attached to a damper blade and installed in the jamb frame of our damper.
PI-50 Blade Position Indicators
2. Actuators with auxiliary switches supplied from actuator manufacturer as an option to the standard actuator construction. The auxiliary micro switch package is built into actuator housing with the electrical wires separate from those supplying the power to the actuator.
For certain applications, the PI-50 and Integral To Actuator packages can alternatively be used for other switching operations such as turning fans off and on.