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STUDOR ® AUSTRALIA Presents. Active Venting System Design Utilizing STUDOR Air Admittance Valves and Positive Air Pressure Attenuators (As per AS/NZS3500.2.2003 Amendment 1 November 2005). Preface:.
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STUDOR®AUSTRALIA Presents Active Venting System Design Utilizing STUDOR Air Admittance Valves and Positive Air Pressure Attenuators (As per AS/NZS3500.2.2003 Amendment 1 November 2005)
Preface: • This presentation is intended to provide the participants with the most current information available at time of publication and draws on Australian National Standards AN/NZS3500.2.2003. • This presentation is at best, a guide, and it is always the installers/designers responsibility to confirm the local regulations, variations, updates and options that apply in their state and/or area.
This Presentation: • should at its completion, : • Inform the participant of the options now available for single fixture, group, stack and relief venting. • 2. Enable the participant to draw a plumbing system showing the correct use of Air Admittance Valves and Positive Air Pressure Attenuators. The Assessment: will be via a hand-drawn sketch sheet at the end of the presentation.
Introduction • It is assumed that the participants in this course have completed the first and second modules of this course or have at least practical experience or knowledge of the installation and application of Air Admittance Valves. • In this module we will learn their applications as to system design.
The Valves MINI-VENT™ MAXI-VENT™ Airflow of7.5 litres/second at -250 Pa Capacity: *60 Fixture units for Group Venting *6 Fixture units for Stack Venting Airflow of 32 litres/second at -250 Pa Capacity: *1000 Fixture units for Group Venting *140 Fixture units for Stack Venting • Both Valves have a lifetime warranty • Both conform to AN/NZS4936 Australian Manufacturing Standard
Important Note *.Always ensure when installing or specifying anyAAV that it is an Australian/New Zealand Standards approved product and has both approval and airflow capacity(l/s) clearly marked on the body of the valve or packaging. On the top of the Mini-Vent and Maxi-Vent are the relevant Australian Standards Marking
STUDOR AAV’s • Are guaranteed for the life of the plumbing system to which they are attached! • Every Mini-Vent and Maxi-Vent has been tested twice before dispatch from the factory!
The STUDOR Mini-Vent & Maxi-Vent • Both AAV’s share a common form of packaging POLYSTYRENE PACKAGING TOP FOR INSULATION MINI/MAXI-VENT OUTER SLEEVE ADAPTER POLYSTYRENE PACKAGING BOTTOM
Installation The Mini-Vent as supplied can beinstalled on 3 different sizes of PVC DWV pipes: • *40mm:to suit basins, small sinks and baths in Australia • *50mm: to suit sinks,laundry tubs etc • *32mm: Older plumbing systems inAustralia (and basins etc in NewZealand) *The Mini-Vent can be installed up 1000mm(1 metre) below the rim/flood level of the highest fixture of the group it is venting
Installation • Note: The capacity of the Mini-Vent is not limited by the pipe size it is connected to but the total number of fixture units it is venting. i.e.: a Mini-Vent can be installed (via reducers etc.) on a 80mm (or above) DWV Waste Pipe if the total number of fixture units doesn’t exceed 60 F.U.
Installation The Maxi-Vent as supplied can beinstalled on 2 different sizes of PVC DWV pipes: • *80mm • *100mm *When used as a group vent the Maxi-Vent can also be installed up to 1000mm(1 metre) below the rim/flood level of the highestfixture in the group it is venting
Group Venting • This plumbing ventilation test rig, the biggest in the world, was built by students and staff at Gymea TAFE in Sydney, to prove AAVs were equal to or better than ‘Open Air Venting’ for groups of fixtures This entire rig was vented by just 2 Mini-Vents
AN/NZS 3500.2.2003 • Clause 6.9 AIR ADMITTANCE VALVES • 6.9.1 Air admittance valves • Air admittance valves complying with AS/NZS 4936 may be used in sanitary plumbing systems for *trap vents, group vents and stack vents and to ventilate branch drains*. They shall not be used for the upstream venting of a main drain. • NOTE: Branches connected into a positive pressure area, such as near boundary traps in multi storey buildings, may need additional venting. • 6.9.2 Requirements for use • The following apply: • (a) Air admittance valves shall be used only on *systems that have at least one open upstream vent off the main drain. The upstream vent shall be sized in accordance with Table 3.5 and shall be not less than DN 50. • (b) Where more than one building on an allotment drains to the sewerage system, the sanitary drainage system of each building shall have one open upstream vent connected to its sanitary drain • (c) Air admittance valves shall have a determined airflow capacity not less than that in Table 6.6 when used as a trap vent, group vent or branch drain upstream vent, and Table 6.7 when used as a stack vent • .(d) An air admittance valve shall not be used as a stack vent where the stack extends through 10 or more floor levels. • (e) Where a sanitary plumbing system has a relief vent fitted to the stack, the relief vent shall be extended separately to atmosphere as an open vent. • (f) In Australia, air admittance valves that form an integral part of a fixture trap shall only be used as a trap vent
Group Venting (Installation) 1 2 Here we see two options; *1. Coming off the 100 x 50 vented Pan bend, (probably the last fixture in the group) *2. Coming off a 100 x 50 Junction on the common discharge pipe
Group Venting Note the connection of the AAV within the cupboard rather than extending the pipe through to the ceiling space.
Group Venting Diagram • Relief Vent to atmosphere * Common Discharge pipes • Clause 7.5.3 and 7.5.7.5.3(b) • Alternative Position Clause 7.5.7.5.2 (b) • Clause 7.5.7.2(a) Fully Vented Modified Clause 7.5.3. • Clause 7.5.7.5. 2 *Refer to Australian National Standards AS/NZS3500.2.2003 • *Please note:Although group vents have been deleted, the relief vent is still required on the stack to maintain air flow and equalize pressures within the stack • The relief vent should also be extended to atmosphere when the stack is vented with a Maxi-Vent. (although in Aust. states with a Performance Code option, Studor advises that this is deleted)
Group Venting • So , knowing that we have to use the Table 6.6 to correctly size our AAV, we now add up the number of fixture units in our group and check the table. • Let’s assume we have 6 W.C.’s (Pan/Cistern combinations) • i.e. 1 x W.C.= 4 Fixture Units • 4F.U.X 6 = 24 Fixture Units
Table 6.6 Minimum Determined Airflow Capacity of Air Admittance Valves When used as a Trap or Group Vent Fixture Unit loading of discharge pipe 6 8 10 12 18 24 30 36 42 48 54 60 Min. Airflow capacity of AAV’s (litres per second) 1 2 2.4 2.7 3.3 3.8 4.2 4.6 5.0 5.3 5.7 6.0 The maximum capacity: STUDOR® Mini-Vent™ 7.50 l/s (or 60 FU) STUDOR® Maxi-Vent™ 32.01 l/s (or 1000 FU)
Stack Venting • The same rule also applies to Stack Venting. • Lets assume 6 x W.C.’s on one common discharge pipe and 6 washbasins on the opposite one and we have the same on 2 floors of a multi storey building. • 6 x 4 F.U.(24FU) + 6 x 1 F.U.(Washbasins)(6FU) = 30 FU X 2 Floors = 60FU Let’s check the next table………..
TABLE 6.7 MINIMUM DETERMINED AIRFLOW CAPACITY OF AIR ADMITTANCE VALVES VENTING DISCHARGE STACKS Fixture unit loading of discharge Minimum determined air flow stack capacity of AAV, Litres per second 1 3 2 4 4 6 6 7 10 9 12 10 15 11 20 13 25 15 30 16 40 18 60 23 80 26 100 29 200 41 300 51 400 58 500 65 600 72 100092
Stack Venting STUDORMaxi-Vent With adapter Push-fit into 100mm DWV pipe with adapter Removal of adapter enables solvent welding to 80mm DWV Adapter allows push-fit over 80mm DWV pipe
Stack Venting • No need to penetrate the roof! When a Maxi-Vent is installed in a roof space, always allow at least 150mm above any insulation
Stack Venting • When installing the Mini-Vent or Maxi-Vent in areas that might be subject to temperatures below 0ْ or above 60ْ, use the top half of the foam packaging for thermal protection ْ • For additional physical protection, where the Maxi-Vent is installed externally, an aluminum cap is available as an cover over the foam packaging.
The Maxi-Vent™ The Mini-Vent™ Traditionally Vented plumbing system A stack and group vented plumbing system using Studor AAV’s Note the saving of unnecessary vent piping/fire collars etc and no roof penetration required *Although not shown here, each plumbing system/building/house etc must have at least one open vent to atmosphere. In some cases this may need to be the main stack, so a Maxi-vent might not be used. Mini-Vents would still be used however for venting single fixtures and bathroom groups
Relief Venting • The relief vent in any multi-storey plumbing system is used to equalize air pressure within the stack. • It is usually a pipe of lesser or equal diameter running parallel to the wet stack pipe that it is venting • Until recently this was the only option available and approved for application to AS/NZS3500, Aust & N.Z.
Relief Venting Now Designers have the option of designing a approved plumbing system without relief venting. The Studor P.A.P.A (Positive Air Pressure Attenuator) can be installed at the base of the stack and at various floor intervals, depending on the height of the building ,without the need for a continuous parallel vent pipe. Designed to utilize standard DWV fittings wherever possible, the PAPA is simply connected directly to the stack either horizontally or vertically to provide protection against positive pressures within the stack.
Relief Venting cont: The P.A.P.A. can also be installed with a Maxi-Vent to provide additional protection against negative pressure As well as in series as per this 40 storey apartment block in Hong Kong
AN/NZS3500.2.2003 Amendment 1 6.10 PRESSURE ATTENUATORS 6.10.1 General Pressure attenuators may be used in sanitary plumbing systems as an alternative to relief venting. Attenuators are used to counter the tendency for the loss of trap water seals resulting from positive pressure pulses in discharge stacks. Positive pressure pulses or transients arise from disruptions to airflow produced at changes of direction or restriction to the airflow path. The size of the pressure attenuator is independent of stack size and fixture unit loading. Although the application of pressure is not limited by building height, this Standard covers installation of pressure attenuators in sanitary plumbing stacks up to 50 floor levels only . 6.10.2 Installation of pressure attenuators Pressure attenuators shall be... (a) connected to stacks by means of 45° or sweep junctions; (b) positioned above the point of connection in either a vertical or horizontal orientation; and (c) adequately supported with allowance for thermal movement. Connections to the stack other than these immediately above the base of the stack or offset, shall be above the branch discharge pipe at that floor level.
Relief Venting (cont) • Pressure attenuators shall be accessible and installed in accordance with Table 6.8. • Where there is no stack offset, the connection for the lowest device shall be between the prohibited connection zone at the base of the stack and the first branch connected to the stack • Where there is a stack offset, the connection for the lowest device above the offset shall be between the prohibited connection zone above the graded offset within the stack and the first branch connected to the stack above that offset • Where the stack extends through more than 25 floors, two pressure attenuators, arranged in series shall be used at the base of the stack. 6.10.3 Location
Relief Venting (cont.) TABLE 6.8 LOCATION OF PRESSURE ATTENUATORS Note: Where the height of the discharge stack above the base or offset is less than 5 floor levels Clause 7.5.3.1 may apply
Relief Venting (cont.) Note: if the P.A.P.A is to be installed with a Maxi-Vent in its top, it is not be installed Horizontally. However if a P.A.P.A is installed complete with a Maxi-Vent this gives the Designer added flexibility in his design as well as additional protection against pressure variations within the stack. The Maxi-Vent will open immediately under negative pressure, allowing air into the stack at the point of need instead of the traditional method of waiting for the air to circulate through the relief vent pipe.
Relief Venting (cont) 7.5.3.1 General If one or more floors separate the floor levels of the highest and lowest branch pipe connected to the stack, a relief vent shall be installed in accordance with Clauses 7.5.3.2 to 7.5.3.5, or pressure attenuators may be installed as specified in Clause 6.10.
Relief Venting (cont) • Relief Vent to atmosphere Note the P.A.P.A installed in place of the relief vent. This now streamlines the system to simply the pipe that transports the waste. • Clause 7.5.3 and 7.5.7.5.3(b) Clause 7.5.7.5.2 (b) • Clause 7.5.7.2(a) This system is Single Stack Modified Clause 7.5.3. • Clause 7.5.7.5. 2
The Studor System Note: This diagram for demonstrative purposes only.
Summary • So now we have learned that plumbing systems can be completely vented with only one open vent to atmosphere and the only pipes required are those carrying the waste. • Please clarify any points with your instructor on which you are unsure • Your Instructor will now hand out a design sheet for you to complete. GOOD LUCK!
Acknowledgements STUDORAustralia would like to thank: - the Teaching and Stores Staff under the guidance of Raymond Jones, Senior Head Teacher of Plumbing,TAFE NSW Southern Sydney Institute, Sutherland College (Gymea Campus) for their support and contribution to this entire course. - All TAFE teachersnationally STUDOR would also like to acknowledge the continued support offered by Plumbers Supplies Co-operative who provided the materials for this project