Maximum Flexible Duct Length Smacna

The flex duct must be adequately supported to ensure the duct is not crimped and to maintain both air flow through the duct and the integrity of the duct coil and insulation material. If you need ductwork for your air conditioning projects or heating project, The Duct Shop will ship your ducts quickly, directly to your home or HVAC job site. Inner Duct: Minimum 0. The friction loss is customarily given as pressure loss for a given duct length, Δp / L, in units of (US) inches of water for 100 feet or (SI) kg / m 2 / s 2. Where the exhaust duct equivalent length exceeds 35 feet (10 668 mm), the equivalent length of the exhaust duct shall be identified on a permanent label or tag. Ashrae 2001 Fundamentals Handbook Duct Design. 028-inch perforated galvanized sheet steel having 3/32-inch- diameter perforations, with overall open area of 23 percent. band) quick release s. ASHRAE DUCT DESIGN. − Provide round neck grilles/diffusers or square-to-round transitions. The way your vent is installed can make the maximum safe length fluctuate considerably. Do not use flexible duct to change direction. If you keep it short(<1. 2 ROUND DUCTS AND FITTINGS A. ® RC insulation is a flexible, fiberglass duct liner. Install duct test holes where required for testing and balancing purposes. 5" WG from the mixing box to the grille. Construct drain pans to extend beyond coil length and width and to connect to condensate trap and drainage. the dryer to the exhaust duct system shall be a single length that is listed and labeled in accordance with UL 2158A. 5 feet per bend. Most technicians are skeptical about these numbers, especially on the Return air side of the system. Airflow – Part 1. externally insulated, spiral wound, flexible duct with a maximum length of 2. Fibrous-Glass Duct Liner: Comply with ASTM C 1071, NFPA 90A, or NFPA 90B; and with NAIMA AH124, "Fibrous Glass Duct Liner Standard. Duct systems serving heating, cooling and ventilation equipment shall be fabricated in accordance with the provisions of this section and ACCA Manual D or. Provide mechanical device identification on or adjacent to access door. Required fields are denoted with an asterisk (*). Class Rating + 50% W/200 on 1/2" on 13"-18" 49"-120" 5/8"on 19"-24" Field: 3/4" on 25"-84" Class Rating + 25% 1" on 85"-120" Tolerance: Tolerance: +7. ^1 Tnstail registers, diffusers, and grilles. No portion of the duct shall rest on the back surface of the ceiling panel and minimum of 4" clearance must be maintained. The answer would be yes. length (maximum) d. smacna-hvac duct construction standards - metal and flexible, second edition 1997, addendum 1, page 1-41-7, table 1-85 Return to Quickfind Index Top of Page 10" W. Flexible duct shall have no bends greater than 45º. Specifically, a larger duct is necessary for the 3660 or 4860 unit before splitting the flow or if the plenum length is more than 150 feet. method(s) b. Each dryer mo del has a maximum ra ted vent length, shown in the product literature that is supplied with each model, or on the Whirlpool. Flexible ducts should have maximum of 1/2-inch sag per foot between supports. Ideally, ducts shouldn't sag more than ½ inch per foot between supports, and maximum sag should not exceed 2½ inches [4E]. Flex ducts do worse at both of those than hard pipe. 5) unless otherwise indicated. Rectangular Industrial Duct Standards, 2004. in reply to flex duct length 6' max. What is the maximum duct length from a bathroom fan? Mike writes: "I'm renovating my bathroom and plan to install a fan. 3" wide tape, position the tape along the edge of the flap in a manner that will allow 1" overlap on adjacetn surfaces. com, we have a large selection of high temperature hose that is designed for long-term use and durability when exposed to elevated temperatures. The inner lining of these flex duct branches have been attached to the collars, but they have not been sealed 30 Figure 39. unit, and reasonable length duct runs. 03 HANSEN HALL – LEVEL 300/400 RENOVATIONS CONSTRUCTION PACKAGE METAL DUCTS 233113 - 3 ards - Metal and Flexible," Chapter 3, "Round, Oval, and Flexible Duct," based on indicated static-pressure class unless otherwise indicated. Insulated Flexible Duct R6 Metalized Jacket is used in HVAC Heating and Air Conditioning systems and venting applications. 003 ft when straight and fully stretched tight at 0% compression (adjusted at other compressions), otherwise the. TOLCO also offers total seismic services including brace layout, engineering calculations and stamp where. This Excel template can be used to calculate velocity and friction loss in air ducts. Ashrae 2001 Fundamentals Handbook Duct Design. Connect diffusers to low pressure ducts directly or with 10 feet (3. The maximum. The flex duct must be adequately supported to ensure the duct is not crimped and to maintain both air flow through the duct and the integrity of the duct coil and insulation material. Install duct test holes where required for testing and balancing purposes. This American National Standard (ANSI/SMACNA 006-2006) contains tables and details for constructing ductwork for ½" to 10" wg positive and negative pressures. [Comment: When a reference is made within this rule to a federal statutory provision, an industry consensus standard, or any other technical publication, the specific date and title of the publication as well as the name and address of the promulgating agency are listed in rule 4101:2-15-01 of the Administrative Code. Air Connectors, identified by a round shape listing mark, GUIDELINES FOR INSTALLING FLEXIBLE DUCT I N S T A L L A T I O N I N S T R U C T I O N. Ceiling plenums, duct chases, and obstructions such as walls and beams often dictate that a cer-tain size duct be used, regardless of whether or not it is the best size from a. pages of free smacna example. Duct systems serving heating, cooling and ventilation equipment shall be fabricated in accordance with the provisions of this section and ACCA Manual D or. How to Install Insulated Flex Duct. Construction: Double wall rectangular duct and fittings to be fabricated in accordance with 2005 SMACNA "HVAC Duct Construction Standards, Metal and Flexible. Fibrous duct construction shall conform to the SMACNA Fibrous Glass Duct Construction Standards or NAIMA Fibrous Glass Duct Construction Standards. The duct is semi rigid (flexible) delivered as a 1 mtr length which extends to 3 mtrs. KINETICS™ Pipe & Duct Seismic Application Manual RECTANGULAR DUCT DATA PAGE 2 of 7 SECTION – A3. The standard gauges also required by SMACNA (2005) are also required; this is standard practice for Lindab. SMACNA - HVAC Duct Construction Standard - Metal and Flexible. PR-25 (25’ length) flexible duct is constructed UL Listed & Labeled with a spring steel wire helix, encapsulated in a Guaranteed out of package lengths 2-ply, air-tight inner core. EASY DUCT TECHNICAL MANUAL THE EASY DUCT ADVANTAGE Simple to install - No special tools or training required Clamp-together components can be taken apart and reused Flexible - Easily connects to existing ductwork Components and adapters fit every system Adjustable duct fittings simplify connections. We provide the best HVAC, Piping & Plumbing Shop Drawings that you can manufacture from at the lowest price in the field. for longer lengths, increase the duct size and provide a duct transition to maintain the duct static pressure drop at or below 0. General Fabrication Requirements: Comply with SMACNA's "HVAC Duct Construction Standards - Metal and Flexible," Chapter 3, "Round, Oval, and Flexible Duct," based on indicated static-pressure class unless otherwise indicated. on how FlexHead flexible sprinkler systems are the easiest, most reliable, and most cost-effective sys-tems available, please call (800) 829-6975today! Or visit our website at www. For optimum performance, make sure that the air duct is short and straight, with a maximum length of 50 linear feet. DUCT SYSTEMS 2015 SEATTLE RESIDENTIAL CODE 501 sealed and mechanically fastened. Permacote Linacoustic HP shall be cut to assure tight, overlapped corner joints. 1—2012 Licensed to Mr Graham Palmer on 13 June 2012. Of course, ventilation may not be adequate if moisture is getting into the house because of improper foundation. SMACNA-Sheet Metal and Air conditioning Contractors’ National Association Inc - "HVAC Duct Construction Standards-Metal and Flexible" - 1995, U. • No flex duct shall pass through any wall, floor, or ceiling. double wall rectangular duct and fittings are one part of our complete line of HVAC products. The cutting blade length should be at least the same length as the wall thickness of the ducting. exchange with the cooling air and obtain maximum thermal Max Duct Length 1-Way 25 50 75 16” One Way Duct Adapter 1 16” x 20’ Flexible Air Duct 2. The SMACNA Testing & Research Institute conducted a comprehensive evaluation of the submittal as an acceptable alternative for use with the SMACNA HVAC Duct Construction Standard - Metal and Flexible, 2nd Edition 1995. Rectangular ducts with duct lagging are often ineffective in reducing duct breakout noise. Certain Connectors are available with 300L series or 316L series stainless steel or aluminum. 23 K value at 75 degrees F. Some installers do this to reduce noise from the air handler. 4 If specimen fails to meet allotted leakage level, the contractor shall modify to bring it into com- pliance and shall retest it until acceptable. Clearance between the sleeve and wall/flooropening shall be a maximum 1/8" per foot on height and width of sleeve to a maximum of 1-1/2" (e. Install flex duct fully extended. Adding up all the lengths and effective lengths. Test and Verification Report on Gripple Hang-Fast Wire Duct Hanger System “Gripple Hang-Fast Wire Duct Hanger Systems Number 2, 3, and 4 as Acceptable Alternatives for Use with SMACNA HVAC Duct Construction Standards Metal and Flexible, Second Edition, 1995”. The exclusive Permacote coating. Fabricate in accordance with SMACNA Fibrous Glass Duct Construction Standards. Model # Diameter Carton Qty. Systems Duct Design manual, there are many other SMACNA publications available that relate to the design and installation of HVAC sys- HVAC Systems Duct Design • Fourth Edition Related SMACNA Publications: xvi HVAC Systems Duct Design • Fourth Edition. achieved if the duct is extended to 90 per cent of its maximum length Flexible ducts shall be adequately supported to eliminate sagging and kinking – a maximum interval between supports of 600mm is recommended. manner or shall be completely encased in concrete not less than 2 inches (51 mm) thick. Maximum Deflection Maximum Test Pressure Joint and Reinf. any type which does not include automatic maximum temperature controls and where operating temperatures of 250°F (121°C) may be exceeded • In kitchen or fume exhaust ducts, or ducts conveying solids or corrosive gases • In any application where the duct liner may come in direct contact with liquid water (such as cooling coils,. Includes rigid duct loss, fitting loss, flex duct loss (@15% compression), and max static pressure for diffusers) Even at a leakage class of 48 (unsealed duct) at the maximum expected operating pressure (. Flexible Duct Materials. General Fabrication Requirements: Comply with SMACNA's "HVAC Duct Construction Standards - Metal and Flexible," Chapter 3, "Round, Oval, and Flexible Duct," based on indicated static-pressure class unless otherwise indicated. {The mid-panel reinforcement for the 140 inch side will be 2 ½ x 2 ½ x 1/8 and will be tied. The duct shall be sloped with a drain pan. Important: The use of duct spacers for direct burial may result in excessive point. This analysis included: minimum and maximum working load ranges that will prevent slip and separation of. and replace non-compliant flexible duct at your cost," says Chick. See a list of many of our standard hangers below and if our standard hangers do not fit your ductwork application, we will fabricate what you need. equivalent length at a velocity of 925 feet per minute. , which was the old standard for fan certification). The inner lining of these flex duct branches have been attached to the collars, but they have not been sealed 30 Figure 39. MAC HVAC Duct Construction Standards Metal and Flexible Third Edition. In general, maximum length shall be 6 feet or less. + 10 m/sec (2,000 fpm): Main supply ducts. The length of the flex duct shall not exceed the distance between the low pressure supply air duct and the diffuser plus 20 percent to permit relocation of diffusers in the future while minimizing replacement or modification of the hard ductwork. material c. I realize it's a function of duct diameter, bends, and duct type, but I'm looking for some general ideas. Unlike other types of flexible duct, UNILOK FR1 has an outer steel rib that ensures the products integrity, and correct diameter, even in the tightest bends. When such reinforcement is needed, it should be in accordance with SMACNA or other applicable standards necessary. The maximum length of 4" rigid (aluminum or galvanized) duct which can be tolerated is shown in the table. Install vertical flex duct hangers at least every 6 feet (1. The benefit of flex duct is lower cost, very airtight and easy to install. The remainder of the branch ductwork shall be sheet metal. All comparisons of cost and performance in this example are based on a design pressure of 2. These guidelines will usually provide a maximum length for ductwork venting a dryer. Connect flexible ducts to metal ducts with draw bands. SMACNA - 2. Spiral Pipe of Texas has a fully capable shop for fabricating all of your rectangular duct needs, in addition to our core products of round and flat oval ducts. Maximum duct length recommend is 50 ft. Steel Air Duct – Min 0. Metal Expansion Joints OVERVIEW: When using Flexicraft metal bellows expansion joints, you can be assured they were designed and built to last. Not to mention that flex duct costs significantly less than other types of duct systems and is easier to store and transport. All double wall fittings are fabricated with stiffening beads on duct sizes 19" wide and larger which have more than 10 square feet of unbraced panel. • Flexible duct shall be supported with a plenum rated fabric hanger strap of 1-3/4" wide. Mechanical fasteners of the speci˜ ed type and length must be used, ensuring no greater than 10% compression of the liner thickness. 10ddn S! Lunuuxeul C/d 09 Sl (M) uolsuoullp tununxeul ual_vw Idaoxa 'Lunu11XBLL1 91 SJonp awnsse C/d. My barometric damper is 6 in then (the flue vent connector goes to 8 in to A manual duct damper, also referred to as a manual. SMACNA Fire, Smoke and Radiation Damper Installation Guide for HVAC Systems 3. Crimp joints for round metallic ducts shall have a contact lap of not less than 1 inch (25 mm) and shall be mechanically fastened by. The maximum duct temperature for plastic ducts shall not be greater than 150°F (66°C). If the designer does not designate pressure class for duct construction on the contract drawings, the basis of compliance with the SMACNA HVAC Duct Construction Standards is as follows: 2" (500 Pa) w. Thermoset FRP Duct Construction Manual, 1997. Details of the air-handling units with its noise levels. The ECCODUCT™ system has a 3-hour fire rating on all encased components and has passed extensive testing to give trouble free installation and service. Rectangular Industrial Duct Standards, 2004. "Length identification. Connect flexible ducts to metal ducts with adhesive plus sheet metal screws. Price $171. Insulated duct is installed in the roof space and any cold void. Precision Duct. Please Note: Prices, promotions, styles and availability may vary by store and online. See a list of many of our standard hangers below and if our standard hangers do not fit your ductwork application, we will fabricate what you need. wg Check the minimum and maximum cfm desired with the minimum and maximum cfm allowed in the table in the general data section. Step 3:Aluminium Tape Application Using minimum 2. In order to give contractors solid information on what needs to happen for a satisfactory. com, we have a large selection of high temperature hose that is designed for long-term use and durability when exposed to elevated temperatures. 9 Connect terminal units to medium or high pressure ducts with 300 mm maximum length of flexible duct. Metal ducts shall be protected from corrosion in an approved manner or. From corners of duct 4" (100mm) Along length of duct 16" (400mm) O. Maximum Flex Duct Length: This is the longest length of a flexible duct segment that can be used in routing solutions for branch ductwork. Great prices & free shipping on orders over USD50!. Kitchen range hoods should be exhausted to outdoors, especially if there is a gas range. The trunk that serves these two ducts needs to be able to deliver 72 + 197 = 269 cfm. This section is based on the format recommended by MICA (Midwest Insulation Contractors Association) and has been revised to include K-Flex USA products and installation recommendations. A good rule of thumb would be that if there would be less than 4 turning vanes across the diagonal of the mitered elbow, then go to the smaller vane. SMACNA CAD Standard Second Edition v NOTICE TO USERS OF THIS PUBLICATION 1. That way, it's possible to regulate the airflow by adjusting the position of the damper. SMACNA Fire, Smoke and Radiation Damper Installation Guide for HVAC Systems 3. Install vertical flex duct hangers at least every 6 feet (1. In addition, Owens Corning Air Handling Solutions Certifi cations and Sustainable features are:. Rectangular Duct Hangers Minimum Size. On this page you'll find a variety of different tools and calculators that will assist with your Hart & Cooley products. The NEC does restrict the length of flexible metal conduit for lighting fixtures to 6 ft to limit the ground return path. Clearance between the sleeve and wall/flooropening shall be a maximum 1/8" per foot on height and width of sleeve to a maximum of 1-1/2" (e. The Flex-Flyte L-1 is a lightweight and flexible hose designed to handle air and fumes at low pressures and moderately high temperatures. Keep the length and number of bends to the minimum. This consists primarily of maximum and minimum system velocities, minimum trunk diameters, air leaving condition, design room temperature, estimated static pressure loss through the central equipment and loss coefficients for 45 and 90-degree elbows as well as fire dampers. Mathematics and pages. Measure the length of straight duct. SMACNA HVAC Duct Construction Metal and Flexible (2005) Table 5-2 allows for a maximum spacing of 12 feet. Be sure to also install a wall or roof cap. (duct) when passing through tight areas. This section provides for furnishing and installing low velocity and high velocity ductwork and includes duct construction and accessories. On this page we will look at common hvac system ells, tees, and reducers. Buy it and Save at GlobalIndustrial. manufactures double wall fittings in most sizes and configurations. What's the max effective duct length for a furance with a four ton AC equivalent blower (~1700-1800CFM). For instance a 2. 9 Connect terminal units to medium or high pressure ducts with 300 mm maximum length of flexible duct. ANSI/SMACNA 006-2006 HVAC Duct Construction Standards Maximum Deflection Maximum Test Flexible Duct. Price: CDN$ 86. Precision Duct. method(s) b. static pressure class and 2500 FPM maximum velocity. pages of free smacna example. Metal and Flexible, 3rd Edition SMACNA 1987 (2006) HVAC Duct Systems Inspection Guide, 3rd Edition SECTION 23 31 13. band) quick release s. 05"wc or less) to size flex duct. Unlike other types of flexible duct, UNILOK FR1 has an outer steel rib that ensures the products integrity, and correct diameter, even in the tightest bends. SMACNA HVAC Air Duct Leakage Test Manual 4. − Provide round neck grilles/diffusers or square-to-round transitions. We provide the best HVAC, Piping & Plumbing Shop Drawings that you can manufacture from at the lowest price in the field. double wall rectangular duct and fittings are one part of our complete line of HVAC products. Looking for DUCTMATE Hypalon, Steel Duct Connector, 50 ft. SMACNA HVAC Duct Systems Inspection Guide 7. I want to Set the flex duct length so when i draw it in freehand it will inform me when i reach my max length. Shop Application of Duct Liner: Comply with SMACNA's "HVAC Duct Construction Standards - Metal and Flexible," Figure 7-11, "Flexible Duct Liner Installation" 1. However, there are a lot of variables that can enter into the equation. Duct reinforcement may be necessary either at the ends of a duct section—in the form of duct section connecting joints—and/or at spaced intermediate locations along the length of a given duct section. flex duct; insulation not shown. Adding up all the lengths and effective lengths. EcoGuard should not be used in duct systems with fan velocities exceeding 4,000 fpm or at temperatures above 250°F. Test and Verification Report on Gripple Hang-Fast Wire Duct Hanger System “Gripple Hang-Fast Wire Duct Hanger Systems Number 2, 3, and 4 as Acceptable Alternatives for Use with SMACNA HVAC Duct Construction Standards Metal and Flexible, Second Edition, 1995”. Connect terminal units to supply ducts[ directly or] with maximum [12-inch (300-mm)] lengths of flexible duct. and the Air Diffusion Council in accordance with ADC Flexible Duct Performance and Installation Standards using ASTM C-518 at installed wall thickness on flat insulation only POlyeThylene JaCkeTS. Spiral duct is available in galvanzied, aluminum and 304/316 stainless steel in diameters ranging from 3" to 60". In addition, Owens Corning Air Handling Solutions Certifi cations and Sustainable features are:. Two 45° turns within the duct length should be. That way, it's possible to regulate the airflow by adjusting the position of the damper. ASTM C 1290, Flexible Fibrous Glass Blanket Insulation Used to Externally Insulate HVAC Ducts, Type III ASTM C 1136, Flexible Low Permeance Vapor Retarders for Thermal Insulation, Type II (facing only) ASTM C 553,*Mineral Fiber Thermal Insulation: Type I – Fiberglas ® Duct Wrap Type 75; Type II – SOFTR Duct Wrap Types 100 and 150. It is commonly sold as boxes containing 25' of duct compressed into a 5' length. The way your vent is installed can make the maximum safe length fluctuate considerably. g-S aas pue E-S 'C-S aas. Available thicknesses for flexible elastomeric duct liner are 3/8, 1/2, 3/4, and 1 inch (10, 13, 19, and 25 mm). • Use Hardcast AFG-1402 Foil-Grip tape, Hardcast DT-Tape with FTA-20 adhesive, or water based paint-on. Performance and installation shall be in accordance with SMACNA HVAC Duct Construction Standards, Metal and Flexible. Fabricate in accordance with SMACNA HVAC Duct Construction Standards - Metal and Flexible and NFPA 96. 5 inches by 16. Maximum Flex Duct Length: This is the longest length of a flexible duct segment that can be used in routing solutions for branch ductwork. 3 Pressure (P) The duct metal thickness and stiffener requirements are based on maximum system design pressures. (12) Where a supply duct is located in a conditioned space, the ductwork shall be sealed to Class C level as described in the SMACNA “HVAC Duct Construction Standard – Metal and Flexible. Advanced VAV System Design Guide. Sheet Metal Duct Friction Loss Calculator. band) quick release s. 1/4" to 24" diameters. Damper Attachment to Sleeve a. TOLCO also offers total seismic services including brace layout, engineering calculations and stamp where. As discussed in our Hvac for Beginners main page, each component of a forced air system, from the filter to each branch duct, adds a certain amount of restriction to the airflow of that system. 05"wc or less) to size flex duct. out-lines a relatively simple duct sizing technique called the Friction Rate Reduction Method. While a duct sizing calculator built for a specific type of ductwork is the best possible method for sizing ducts, the attached chart can be used in most single story homes with a centrally located unit, and reasonable length duct runs. SMACNA HVAC Duct Construction Metal and Flexible (2005) Table 5-2 allows for a maximum spacing of 12 feet. This section is based on the format recommended by MICA (Midwest Insulation Contractors Association) and has been revised to include K-Flex USA products and installation recommendations. The procedure is as follows: 1. free smacna condition of range ride. IR is the intermediate reinforcement required. In general, maximum length shall be 6 feet or less. General Fabrication Requirements: Comply with SMACNA's "HVAC Duct Construction Standards - Metal and Flexible," Chapter 3, "Round, Oval, and Flexible Duct," based on indicated static-pressure class unless otherwise indicated. from the end caps. Most technicians are skeptical about these numbers, especially on the Return air side of the system. From corners of duct 4" (100mm) Along length of duct 16" (400mm) O. wg, to 36 in. OR If the duct is flexible insulated, multiply by 1. Reading Guide - For duct sizes between, say, 651 mm and 700 mm, when the pressure class is 1” w. It is easily cut to length using a sharp knife and pliers. Surface-burning characteristics in first subparagraph below are available in limited thicknesses. For example, if a flex hose is listed as having a 6:1 compression ratio, that hose can be compressed from a full 6ft down to 1ft. Maximum length shall be 18 in. Comply with SMACNA's "HVAC Duct Construction Standards--Metal and Flexible" for acceptable materials, material thicknesses, and duct construction methods, unless otherwise indicated. Ceiling plenums, duct chases, and obstructions such as walls and beams often dictate that a cer-tain size duct be used, regardless of whether or not it is the best size from a. This fourth edition includes a variety of updates that reflect industry innovations that impact the construction, installation and repair of HVAC ductwork – both metal and flexible ducts. Transverse restraints for one duct section may also act as a longitudinal restraint for a duct section of the same size perpendicular to it if the restraint is installed within 24-inches of the elbow centerline or tee or combined stresses are within allowable limits at longer. Squeezing flex duct through tight spaces. 3 Leakage test procedures shall follow the outlines and classifications in the SMACNA HVAC Duct Leakage Test manual. 181 Class 1 (maximum flame spread: 25, maximum smoke developed: 50). ducts, but do supply the flexible duct industry with fibrous glass insulation. Permacote® Linacoustic® HP Fiber Glass Duct Liner Description Permacote Linacoustic HP is a flexible duct liner insulation made from strong glass fibers bonded with a thermosetting resin. This is the default type for flexible duct for branch ductwork (Flex Duct Round : Flex - Round, or None). Lengths: Fabricate rectangular ducts in lengths appropriate to reinforcement and rigidity class required for pressure class. It is commonly sold as boxes containing 25' of duct compressed into a 5' length. Some installers do this to reduce noise from the air handler. 5) unless otherwise indicated. Allowable Leakage based on SMACNA Leakage Class SMACNA and NEBB recommend use of leakage class for specifying allowable leakage. Choose a fan that is certified at 0. Using either a single- or dual-wall round duct with a radiused elbow coming off the discharge section of the fan can reduce duct breakout. 2 ROUND DUCTS AND FITTINGS A. SMC manufactures coil line ductwork in 4'-5'-6' lengths. Maximum length shall be 18 inches with no intermediate seams. Shop Application of Duct Liner: Comply with SMACNA's "HVAC Duct Construction Standards - Metal and Flexible," Figure 7-11, "Flexible Duct Liner Installation" 1. The corner length in each direction equals 32 times the thickness of the duct (t) for this purpose. Click Here to Order Online Now. Install coils in metal ducts and casings constructed according to SMACNA's "HVAC Duct Construction Standards, Metal and Flexible. For each terminal (wall cap, roof jack), add 30 feet. Back of calculator has equivalent feet of straight duct for commonly used fittings, corrected pressure drop chart, and many HVAC formulas. [Image Can Not Be Found] Posted by Ralph Koerber. For support of the duct it would require a strap or support of a minimum of 1. It is able to endure temperatures between -4°F and +176°F. maximum recommended air quantity (litres per second) flexible duct diameter (mm) 44 l/s Ø 150 92 l/s Ø 200 170 l/s Ø 250 275 l/s Ø 300 385 l/s Ø 350 503 l/s Ø 400 636 l/s Ø 450 785 l/s Ø 500 950 l/s Ø 550 revision 14/04/03 b-ds 1 flex sizing flexible ductwork flexible duct sizing guide. 6 lb 931141 RSC7X6 6" 6 7 lb 931660 Top Take-Offs • For transition from air plenums or rectangular duct to round pipe or insulated flexible duct. The duct will be 18 gage {The joints will be TDC/TDF {The joint length is 56 inches {The 140 inch side will be supported by 1" EMT conduit spaced 46 5/8" across the width and will be at each side of the joint and backing up the mid-panel reinforcement. Flex duct intentionally left too long. ACCA and SMACNA. Increase duct sizes gradually, not exceeding 15 degrees divergence wherever possible; maximum 30 degrees divergence upstream of equipment and 45 degrees convergence downstream. To deliver at least 197 cfm you will need at least a 9″ duct. Mathematics and pages. SMACNA HVAC Duct Systems Inspection Guide 7. " The listing label on a flexible air connector is circular in shape and states "Listed Air Connector. Duct leakage testing pressurizes a closed section of ductwork to a known pressure. Notice that the length you are allowed to safely run the dryer vent depends on which style of duct your use, the amount of elbows needed and type of vent hood. This is the default type for flexible duct for branch ductwork (Flex Duct Round : Flex - Round, or None). com website. good residential design usually uses velocities of 700 to 900 fpm for supply and 600 to 700 fpm for return. If you need ductwork for your air conditioning projects or heating project, The Duct Shop will ship your ducts quickly, directly to your home or HVAC job site. Before sizing a duct system, we have to lay out all the ducts. Resistance to flow through bends is expressed in feet of straight flex duct. UNILOK FR1 Acoustic Ducting is a flexible duct manufactured “tough” & “whisper quiet” for consumer & installer peace of mind. Maximum Flex Duct Length: This is the longest length of a flexible duct segment that can be used in routing solutions for branch ductwork. This consists primarily of maximum and minimum system velocities, minimum trunk diameters, air leaving condition, design room temperature, estimated static pressure loss through the central equipment and loss coefficients for 45 and 90-degree elbows as well as fire dampers. exchange with the cooling air and obtain maximum thermal Max Duct Length 1-Way 25 50 75 16” One Way Duct Adapter 1 16” x 20’ Flexible Air Duct 2. Install flexible duct connectors immediately adjacent to equipment in ducts associated with fans and motorized equipment supported by vibration isolators. QuietR® Duct Liner products shall be cut to assure overlapped and compressed longitudinal corner joints. The internal steel helix resists distortion during installation. (This ideally is carried out by 2 people, one at each end ensuring that the insulation and sleeve extends with the aluminium ducting). General Fabrication Requirements: Comply with SMACNA's "HVAC Duct Construction Standards - Metal and Flexible," Ch. A turn of 45° or less may be ignored. Connect flexible ducts to metal ducts with draw bands. Polyken 367-17, Printed, 2 mil dead soft printed aluminum foil backing with 15 mil adhesive blend. Mostly it would be in millimeters. Unscrew the nozzle and cut opening to desired length. Lightweight duct, core of corrosion resistant reinforcing wire helix permanently bonded within fabric, insulated with 1-1/2" thick, 3/4 lb. No one can offer greater security or variety in meeting your needs for steam or any other applications. Free 2-day shipping. static pressure class and 2500 FPM maximum velocity. By conducting Joint Performance Testing as described in Chapter 11 of the SMACNA HVAC Duct Construction Standards, 3rd ed. Transition ducts shall be a maximum of 8 feet (2438 mm) in length and shall not be concealed within construction. SINGLE WALL All round spiral duct and fittings shall be manufactured from G-90 galvanized steel, conforming to ASTM and SMACNA standards. NOTE: See Section 4 of the SMACNA leakage test manual for normal classification. Charts listed below show what duct diameter to use given a CFM and Velocity. Surface-burning characteristics in first subparagraph below are available in limited thicknesses. Sometimes, however, hurried installations create poor-quality results - as they can for any HVACR product. 5m),it may keep its circular shape and possibly may not need to support it. 2 SHEET METAL MATERIALS A. 1 Response Due to Seismic Loads The methodology for seismic analysis is provided in subsection 3. Metal ducts shall be protected from corrosion in an approved manner or. The chart for the long vent model of the same dryer shows a dramatic increase in allowable vent length. Flexible Duct Connectors Hypalon coated fibreglass material 24 oz. flex duct; insulation not shown.