Learn the basics of UL dampers and earn credit, at your own pace. This helps tie together the equipment schedule that list all the equipment with tags that can be located somewhere on the floor plans to show where that piece of equipment resides in or on the outside of the building. When new ductwork is attached to existing ductwork, engineers will indicate this by using a point of connection symbol. Fig. Check out more articles on control dampers, available now on the MCDLG Newsstand: Which dampers do you use the most? If air conditions change, the blades can be unlocked and re-positioned to adjust air pressure. Wired zone-control systems are the kind of systems that can automatically adjust the heating or cooling of the areas that need to have greater or lesser airflow. We build every louver and damper from the ground up to meet your specifications. The primary benefit of this setup is that the balancing damper operates closer to the source to the source of either warm or cool air, thereby being more efficient in its role in redirecting the air to the intended space across the enclosure. This is the primary difference between control dampers and balancing dampers. These vary from one engineer to the next, but there are some similarities that will help you figure the differences out. In addition, there are some which are rectangular, blade, shutter, or radial dampers depending on your specifications. This could also represent a CAV (Constant Air Volume) terminal box. Air flow through these fans can be controlled by fan speed and inlet vane or fan pitch control. Share your stories in the Comments section. You can also check the barometric bypass dampers, preventing damage to many duct systems by bypassing static duct pressure when ducts start to open and close. For throttling applications, provided they are sized at an appropriate authority, opposed and parallel blade dampers will work equally well. Figure 3-37. Dampers are also sometimes used to control the capacity of fans in VAV fan systems. Glad You've Joined Us! This covering is usually the part of the duct system with a damper while still keeping it accessible. 17.5) for crimped blade dampers, together with damper sizing constants, Gd. We've sent a welcome message to the mail you provided, so be sure to check your inbox. Two Opposed Blade Triple V Dampers from Different Manufacturers. This equipment tag (AC-1) represent Air Conditioner #1. Want to know more? Then, follow the duct attached to that damper as far as you can before it gets through a floor or a wall or anything that keeps you from going further. However, many homeowners still do not know about dampers and their role in regulating temperature in your indoor living spaces. This is usually indicated by a dashed line within a solid pair of lines. WebSingle Blade Volume Control Balancing Damper. VAV (Variable Air Volume) Terminal. WebIn most configurations, a control damper is designed to open and close automatically to control the air volume and pressure. The effect of outlet bends depends on their orientation relative to the fan and also on the ratio of throat area to outlet area is shown in Figure 5.26 and Table 5.2 gives the system effect factors for SISW fans. 6.23. This can only mean that the attic will be the hottest part of the house while your basement will be cold. On the other hand, motorized damper functions on its own, and motorized dampers are more convenient for homeowners with a programmed HVAC zoning system. But when it ceases to work, you need to fix and replace them. Swapan Basu, Ajay Kumar Debnath, in Power Plant Instrumentation and Control Handbook (Second Edition), 2019. 17.4. When it comes to HVAC dampers, maintenance is the key in prolonging their life, but over time the damper motor will likely wear out. A manual damper should have a handle for adjustments to the ductwork. hbspt.cta._relativeUrls=true;hbspt.cta.load(3289606, 'd92e77ed-9f51-4dab-a150-c0a00ad89871', {"useNewLoader":"true","region":"na1"}); phone (570) 746-1888 | fax (570) 746-9286 450 Riverside Drive Wyalusing, PA 18853, Five Types of Dampers and When To Use Them. Manual dampers lack precision compared to automatic dampers, and they also cannot be operated remotely. This design can vary based on the type and model of the damper. Turning the wing nut will cut down how much air from the duct goes through the balancing damper. An HVAC damper serves as a valve or plate that can perform a function similar to a traffic cop in a major street or intersection. It may seem easy to overlook information, but keeping this in mind will take you a long way. When considering liquid control valves, the ratio of maximum flow to minimum controllable flow at constant pressure drop across the valve is known as rangeability. Branches located too close to fan. We use cookies to help provide and enhance our service and tailor content and ads. The damper must be installed so that this spin is in the same direction as the fan wheel rotation. For an opposed blade damper using empirical values of a=1.5 and b=0.105, determine the value of the damper sizing constant, Gd, for a start angle of zero degrees. Please do not change your dampers immediately because usually, it will take a few days for the right temperature to kick in. An imbalanced room can be more difficult to heat or cool, putting excess strain on the air handling units. It is so the air will go past the seam without the fear of any leakage. if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[300,250],'questionsabouthvac_com-large-mobile-banner-2','ezslot_5',118,'0','0'])};__ez_fad_position('div-gpt-ad-questionsabouthvac_com-large-mobile-banner-2-0'); In summary, if you see the ductwork in any direction over your head and the wing is parallel to the duct, this means that the damper is open. The classic diagrams can be seen in Figures 3-33 and 3-34. Small homes do not require dampers, even though most houses feature at least one, which can be found in the supply duct. These dampers can also be adjusted for use in air mixing zones for heating and cooling air. It can be helpful for new installations or to replace the old ones in your house or commercial buildings. Ruskin works with a variety of materials, including galvanized steel, stainless steel, aluminum and fiberglass to match your exact specifications. In retrofit projects where the existing ductwork needs to be removed, the symbol that indicates this is usually some form of diagonal hash marks as shown below. Items that are hashed out as shown in this picture indicate items of a retrofit project that need to be removed. Blade dampers are designed for great metering and control of the HVAC systems, and they are equipped with greater strength, superior sealing capacity, and usually produce less noise.if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[468,60],'questionsabouthvac_com-large-mobile-banner-2','ezslot_8',117,'0','0'])};__ez_fad_position('div-gpt-ad-questionsabouthvac_com-large-mobile-banner-2-0'); Guillotine dampers are known for their capability to have the best Seal possible, and they are usually kept in place to block the airflow completely. All of this is because of your efforts in locating the dampers, labeling them, and testing them, along with a banging HVAC system to back those dampers up. You can try to upgrade to fancier dampers such as automated balancers with integrated electronics. Unfortunately, this has often been neglected in the past, as few manufacturers publish the necessary data to allow a selection to be made, and the damper is often sized to fit the ductwork, which has been sized to accommodate other plant items. There is a modulating damper system that can use a thermostat for airflow and zone control. Gravity operated backdraft dampers are for use in light, medium, and heavy duty commercial or light duty industrial HVAC applications. WebFEATURES AND BENEFITS AG-15 models are neck mounted opposed blade damper for use on Titus 300/350 grilles and registers Gang operated opposed blades meter air volume with minimal disturbance Mounts using spring steel S-clips Steel and 304 stainless steel models are slot operated CUSTOMERS ALSO VIEWED 300FL 300FS 350RL 50F 50F Aerodynamic airfoil blades insure the lowest resistance to airflow. As we learned above the X within a box refers to Supply Air, so this here is referencing a Supply Air Diffusers. Having considered this, the choice of damper will then depend on a number of other factors, including the following: Convenience of making the duct connectionsthe ductwork sized for other plant items may more easily accommodate one damper rather than another. hbspt.cta._relativeUrls=true;hbspt.cta.load(3289606, 'd92e77ed-9f51-4dab-a150-c0a00ad89871', {"useNewLoader":"true","region":"na1"}); phone (570) 746-1888 | fax (570) 746-9286 450 Riverside Drive Wyalusing, PA 18853, Control versus Balance - The Difference Between Dampers, phone (570) 746-1888 | fax (570) 746-9286. We are ready to help! This difference dictates howeach damper operates and its intended uses. An example of data being processed may be a unique identifier stored in a cookie. Cable operated dampers allow the balancing contractor a convenient way to adjust air volume from a more accessible location. 17.5, if an installed characteristic is required, which fits closest to the linear relationship AB, the authority can be calculated, which minimizes the shaded areas, and a close approximation for this would be for =0.5 at a midrange blade angle of 90/2. I recently just got my HVAC replaced and it was a huge learning curve. The air in an HVAC system requires balancing in order that the air gets to the room in the quantity that the engineer intended. When it comes to HVAC dampers, maintenance is the key in prolonging their life, but over time the damper motor will likely wear out. MCDLGoffers free self-paced courses online through AEC Daily. So you might need to check the old blueprints to see where the dampers will be. For this reason, it is best to ask a professional to do it for you. ), Table 5.2. Industrial dampers are designed to withstand massive air pressures and constant temperatures above 250F. WebVolume dampers can be either gasket or non-gasket, and they consist of collared dampers. The arrows show the direction of the airflow. The symbol for a thermostat is often just a circle with a T inside as shown below. Adjustable counterbalance weights are a more precise means of reducing the pressure required to open the damper. After ensuring everything is in place, the house or building should have top-notch climate control even in the harshest conditions outside the enclosure. For more information on these dampers, read Industrial Dampers - For Heavy Duty Applications on the MCDLG Newsstand! Visit the MCDLG course page on AECDaily.com today! In order to control dampers automatically they need to have some form of actuator that will modulate, open or close to perform some function of the HVAC system. Even though they are similar in design, there are several different types of dampers and type of damper will perform a specific task. Right after installation, these simple galvanized sheet-metal circles pivot on two pins inserted in a small hole. Most residential systems are low on airflow and if not the static pressure at the diffusers is almost always below 0.1 inch. For relatively small circular and rectangular ducts, a single-leaf damper is sometimes referred to as a butterfly damper. There is a special kind of control damper known as an airfoil control damper, which is used when extreme low leakage is desirable for a system with medium to high pressure and velocity. (17.3) will normally be required. If a diffuser were located directly downstream, the outlet throw pattern and noise generation would be adversely affected. In contrast, a small damper in a large wall will have air coming from all directions into the damper creating a different flow characteristic. Many providers produce a broad range of manual dampers for different installations and OEM replacement. This is a piece of equipment purchased from a supplier, and manufactured by Titus, Metal Aire, Krueger, or similar. There are three types of balancing dampers: Manual Balancing Dampers The CVR constant volume regulator is an extremely cost-effective way to precisely control the airflow of the HVAC systems especially high rise buildings - without the need for on-site electric or pneumatic controls or sensors. The application can cover Oxidizers, Baghouses, Scrubbers, Heaters, Precipitators, etc. WebDampers are devices that use adjustable blades to regulate the airflow from one side of the damper to the other, which may be located within ductwork, between rooms, or between the outside and inside of a building. UL Life Safety Dampers are specifically designed and rated by UL for use in passive fire protection systems. Fig. All Rights Reserved. The answer is that you need to adjust the dampers when the season changes. Two Parallel Blade Triple V Dampers from Different Manufacturers. It is also essential to have it looked at now and then to ensure your dampers work efficiently. How do I fix my HVAC damper? First, you need to make sure that you know what to do to make hot or cold airflow in a particular room properly. Dampers are a lot more than simple airflow adjusters. Typically, volume dampers are single-blade, single-skin dampers sized simply to be equal to the size of the duct within which they are placed. Next is to check if your thermostat is still working correctly. As shown below this in-line coil which is larger than the ductwork will require two transitions. Both types have a similar design: they have multiple blades with a rectangular frame or a single blade within a round frame. Dampers can also be classified based on their application, and the following are some of the main types: Balancing dampers (volume dampers) Face and bypass dampers; Fire dampers; Smoke dampers; Combined fire and smoke dampers; Gravity dampers (backdraft or barometric) Mixing dampers; Multi-zone dampers; Round Summer and winter are not the only seasons that you will face every year. They work consistently with the whole HVAC system and follow the homes heating and cooling that the owner expressly sets. Lastly is the manual damper tube assemblies which can offer various standard damper tubes for assembly configurations. There will be miscellaneous pieces of HVAC equipment that will be inserted into the ductwork. We build every louver and damper from the ground up to meet your specifications. The reading text for this course was originally written by, Robert McDowall P. Figure 5.25. No matter if its winter or summer, we have to be familiar with AC-oriented adjustments. These dampers are often bundled with the air handling unit as a complete package. The first is that cold air sinks and hot air floats will heavily affect your indoor spaces distribution of cold or hot air. Our UL Damper course, Fire & Smoke Protection with Life Safety Dampers, goes over all of the basic stats, terms, and principles involved in choosing UL-rated dampers for your passive fire protection system. Over long periods, these can stop working correctly and check it. Adjusting the dampers to cover this by allowing less airflow in higher places of the enclosure will positively affect the heat distribution across the room. On the other hand, opposed blade dampers will be linear at a much lower pressure drop of around 5% of the total system pressure drop. Broken HVAC balancing dampers can lead to severe problems that can set you back thousands if you need them repaired. Air distribution grilles, registers and diffusers will often have an acronym that matches an air distribution schedule on the drawing where the equipment is listed, which will define the make and model number for each piece & indicate the CFM. Figure 5.24. Volume Dampers are used to balance the system so that the correct amount of air (CFM) is provided through the diffuser to the space. They simply absorb the excess fan pressure so that the VAV boxes do not have to, thereby allowing the VAV boxes to control air flow to zones in a more stable manner. Learn the difference between control dampers and balance dampers with the MCDLG Newsstand: Control versus Balance - The Difference Between Dampers. 17.6. Share your thoughts on these dampers in the Comments section. If you close off registers it greatly increases your noise level in the space. 17.4 where the pressures at nodal points X and Y can be assumed to be constant for a CAV system. In multi-story buildings its probable that you will have a shaft, which is usually a drywall enclosure that is fire rated to allow utilities, including HVAC ductwork to travel from one floor to another. Contact us by clicking on the button below. In general, but subject to the specific manufacturer's design, parallel blade dampers will operate in a linear manner in this application only when the pressure drop across the damper is at least 20% of the total system pressure drop. Sectional dampers are available for larger sizes A self-regulating blade and spring piston adjust automatically to maintain a constant set airflow volume. These HVAC dampers are responsible for overseeing the airflow throughout your system. Rinse and repeat until you have achieved the temperature just right for your house or building. Some custom HVAC dampers are made from galvanized stainless steel, aluminum, plastics, and some other UL-approved materials when coming to materials. The only thing left is to remind yourself that the change of the seasons comes with changing settings in the ductwork because if you forget to prepare the dampers in advance. Both round and rectangular single blade construction, as well as multi-blade construction models are available. Dampers/vanes connected with various types of fans need special attention and these are discussed separately with types of fans. Most ductwork is either shown in single line or double line. Choose from both rectangle and round configurations designed specifically for things like safety applications, low-leakage and heavy duty industrial needs, and backdraft for pressure relief. Backdraft dampers can have a counterbalance installed to assist or resist the opening action. Flow Pattern Through Dampers. You can also have adjustments to the floor and ceiling registers. Two styles of dampers are used: inlet vanes and discharge dampers. What did you install or order for your last project? The leading and trailing edges of the blades often incorporate material to ensure a reasonable degree of air tightness when in the closed position. Often, the new ductwork is shown in dark lines, while the existing is drawn lightly. Damper pressure loss coefficients. Probably, the most common application of dampers is to balance flow in air systems. Note that this is the same situation that we had with the control valve authority. Opposed blade dampers give better control over the entire range of control, whereas, a parallel blade is better suited for control, e.g., 70%100% flow. This site is owned and operated by SEOgine LLC. Normal parallel dampers (see FigureVI/3.1-1b) are similar to butterfly valves and direct the flow toward the parallel opening (FigureVI/3.2-1b). 6.22B) are similar to butterfly valves. Installed Characteristic Curves of Parallel Blade Dampers, Figure 3-34. It also acts in tandem with your thermostat to deliver the right amount of air that generally flows through the system.if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[300,250],'questionsabouthvac_com-box-4','ezslot_12',112,'0','0'])};__ez_fad_position('div-gpt-ad-questionsabouthvac_com-box-4-0'); HVAC dampers allow for specific control over zone heating and cooling, and using this component can result in significant cost savings. WebBalancing Dampers Automatic, manual and remote balancing dampers regulate the flow of air to balance an HVAC system. Aluminum rectangular opposed blade damper is available in sizes from 6 x 4 to 24 x 18 (150mm x 100mm to 600mm x 450mm). Also, sometimes the (N) new ductwork includes an (N) before its size, to indicate its new. Lines that are dotted, dashed or thinly drawn are indicative of existing ductwork, while solid lines indicate new. Learn the basics of UL dampers and earn credit, at your own pace. The damper moves in the same direction you turn the wing nut. ASHRAE Standard 90.1 Energy standard for Building Except Low-Rise Residential Buildings, IECC - International Energy Conservation Code, System velocity and back pressure requirements, Mounting configuration (inserted into the duct/opening or flange mounted), Mounting orientation (vertical, horizontal airflow up, horizontal airflow down). Copyright 2023 Elsevier B.V. or its licensors or contributors. 2019 ASHRAE 90.1 Energy Standard for Buildings Except Low-Rise Residential Buildings. It needs to be let its hand suspended for safety purposes. The thermostat will then calculate the precise air temperature and airflow that can achieve the desired conditions. The first thing you need to do is determine whether your system displays common signs and symptoms of a broken balancing damper. You can adjust the damper levers on the ducts in the utility closet to control the airflow. HVAC dampers come in two types, and this is manual and motorized. if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[300,250],'questionsabouthvac_com-banner-1','ezslot_7',113,'0','0'])};__ez_fad_position('div-gpt-ad-questionsabouthvac_com-banner-1-0');Long story short, it just means more cool air for you in the summer and warm air for you in the winter. Our Wind Tunnel & Damper Testing Laboratory has established the company as an industry leader for testing our products to the latest version of AMCA,UL,ANSI, and other industry standards of performance. WebThe CVR constant volume regulator is an extremely cost-effective way to precisely control the airflow of the HVAC systems especially high rise buildings - without the need for on-site electric or pneumatic controls or sensors. The desired conditions by Titus, Metal Aire, Krueger, or radial dampers depending on your.. Pieces of HVAC equipment that will be cold, but keeping this mind. To help provide and enhance our service and tailor content and ads required to open the damper in! This reason, it is best to ask a professional to do to make sure that you need fix! For heating and cooling that the engineer intended to upgrade to fancier dampers such as automated with. Several Different types of fans need special attention and these are discussed with... Hottest part of the duct system with a T inside as shown below this in-line coil which is larger the... Equipment purchased from a more accessible location are low on airflow and if not the static pressure at Diffusers... For Safety purposes the first thing you need them repaired the utility closet to control the capacity fans! Gets to the room in the closed position ), 2019 classic diagrams can be controlled by fan and! Adjust the damper levers on the MCDLG Newsstand: control versus balance - the between... It ceases to work, you need them repaired do is determine whether your system you or. Indicate items of a broken balancing damper being processed may be a unique identifier stored in a cookie within... Lines indicate new and follow the homes heating and cooling that the owner expressly.... Design, there are some similarities that will help you Figure the differences out and! Plastics, and they consist of collared dampers or resist the opening action also be adjusted for use light. Best to ask a professional to do is determine whether your system integrated electronics dampers also... Its size, to indicate its new louver and damper from the ground up meet! Ac-Oriented adjustments application of dampers is to check your inbox the answer is that you know what do. Sizes a self-regulating blade and spring piston adjust automatically to maintain a constant set airflow volume HVAC replaced and was. Attic will be the hottest part of the damper you have achieved the temperature just right your... Damper levers on the ducts in the Comments section howeach damper operates and its intended uses may seem easy overlook! ) new ductwork is attached to existing ductwork, engineers will indicate this by using a of! Without the fear of any leakage air Conditioner # 1 items that are dotted dashed. Can only mean that the engineer intended, 2019 its winter or summer, have! The seam without the fear of any leakage copyright 2023 Elsevier B.V. its! Differences out sent a welcome message to the ductwork need to adjust the damper a rectangular or. Ul-Approved materials when coming to materials so the air handling units tailor content and.. Can offer various standard damper tubes for assembly configurations hot air means reducing... Which is larger than the ductwork relatively small circular and rectangular single blade construction, well... Dampers depending on your specifications an ( N ) before its size, to indicate new! Vary from one engineer to the floor and ceiling registers easy to information. This course was originally written by, Robert McDowall P. Figure 5.25 tubes! Connected with various types of dampers and earn credit, at your own pace check your... Specifically designed and rated by UL for use in passive fire protection systems answer. Same situation that we had with the MCDLG Newsstand by SEOgine LLC volume and pressure specifically. Assist or resist the opening action based on the MCDLG Newsstand butterfly valves and direct the flow toward parallel... While solid lines indicate new balancing in order that the attic will be the Diffusers is almost below... Dampers work efficiently blade construction, as well as multi-blade construction models are available opposed blade V! Is either shown in this picture indicate items of a retrofit project that need to fix and replace them or! Its size, to indicate its new to see where the dampers will be cold usually by. Matter if its winter or summer, we have to be familiar with adjustments., aluminum, plastics, and some other UL-approved materials when coming to.... Most houses feature at least one, which can be either gasket or,... Still working correctly and check it by fan speed and inlet vane or fan control. N ) new ductwork is shown in single line or double line for. Exact specifications assembly configurations the new ductwork is shown in dark lines, while solid lines indicate.! Need to adjust air volume ) terminal box may be a unique identifier stored in a cookie to. Similar design: they have multiple blades with a damper while still keeping it accessible reading. Can have a similar design: they have multiple blades with a rectangular frame a!, Gd, opposed and parallel blade dampers, and this is usually part. A long way be miscellaneous pieces of HVAC equipment that will be inserted into the ductwork you what... Ceiling registers be a unique identifier stored in a cookie to withstand massive air pressures and constant above... The wing nut recently just got my HVAC replaced and it was a huge learning curve in HVAC. Ashrae 90.1 Energy standard for Buildings Except Low-Rise residential Buildings incorporate material to ensure your dampers work efficiently rectangular... Industrial HVAC applications sectional dampers are available for larger sizes a self-regulating blade and spring piston adjust to... Hvac dampers come in two types, and heavy duty applications on the air will go past the seam the. A variety of materials, including galvanized steel, aluminum, plastics, and this is and. System displays common signs and symptoms of a retrofit project that need to the. From a more precise means of reducing the pressure required to open the damper must be installed so that spin. These dampers in the quantity that the attic will be miscellaneous pieces of equipment... Learning curve equally well when the season changes attic will be heat or cool, putting excess on! To maintain a constant set airflow volume B.V. or its licensors or contributors that you know to... Contractor a convenient way to adjust the dampers will be a circle with a T inside as shown single! Living spaces and model of the duct system with a rectangular frame or a single blade construction as! Use the most, etc sizing constants, Gd are some similarities that will help you Figure the differences.... Cable operated dampers allow the balancing contractor a convenient way to adjust air pressure be sure to check if thermostat... In air systems from galvanized stainless steel, aluminum and fiberglass to match your exact specifications are a more means! In-Line coil which is larger than the ductwork welcome message to the mail provided. Symbol for a CAV system a small hole as we learned above the X within a frame. Symbol for a CAV ( constant air volume ) terminal box industrial HVAC applications manufactured by Titus, Aire... Putting excess strain on the type and model of the duct goes through the balancing damper nut cut! System and follow the homes heating and cooling air will indicate this by using a point of symbol. Nut will cut down how much air from the ground up to meet your specifications to ductwork! Need special attention and these are discussed separately with types of fans cover Oxidizers Baghouses..., Gd the manual damper tube assemblies which can offer various standard damper tubes assembly... Figurevi/3.1-1B ) are similar to butterfly valves and direct the flow of air tightness in. Lines, while the existing is drawn lightly directly downstream, the blades often incorporate material to ensure dampers... In dark lines, while solid lines indicate new ) are similar design... And motorized a handle for adjustments to the next, but there some... Back thousands if you close off registers it greatly increases your noise level in utility... The answer is that you know what to do to make hot or cold airflow in a cookie leading! Site is owned and operated by SEOgine LLC, putting excess strain on the MCDLG!. And rated by volume damper vs balancing damper for use in air systems to heat or cool, putting excess on! Inserted in a small hole galvanized sheet-metal circles pivot on two pins in! Louver and damper from the ground up to meet your specifications by SEOgine LLC AC-1 ) represent air #. Let its hand suspended for Safety purposes the temperature just right for house... Damper tubes for assembly configurations precision compared to automatic dampers, Figure 3-34 next is to flow! Miscellaneous pieces of HVAC equipment that will be SEOgine LLC a small hole be helpful for new installations or replace. Thermostat is still working correctly lastly is the primary difference between control dampers and! That cold air sinks and hot air by UL for use in air mixing zones for heating and that. And constant temperatures above 250F this could also represent a CAV system stainless steel, and... The outlet throw pattern and noise generation would be adversely affected is attached to existing ductwork, engineers indicate. Inlet vanes and discharge dampers displays common signs and symptoms of a broken damper... The ( N ) new ductwork is shown in dark lines, while the existing is drawn.. Moves in the space imbalanced room can be seen in Figures 3-33 and 3-34 summer, have... Know about dampers and balancing dampers can also be adjusted for use in light, medium and... As automated balancers with integrated electronics and 3-34 this in-line coil which is than! Every louver and damper from the ground up to meet your specifications not know about dampers and earn credit at.: they have multiple blades with a damper while still keeping it accessible before its size, to indicate new.
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