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:.
Active Venting System Design
Utilizing STUDOR Air Admittance Valves and
Positive Air Pressure Attenuators
(As per AS/NZS3500.2.2003 Amendment 1 November 2005)
will be via a hand-drawn sketch sheet at the end of the presentation.
Airflow of7.5 litres/second at -250 Pa
*60 Fixture units for Group Venting
*6 Fixture units for Stack Venting
Airflow of 32 litres/second at -250 Pa
*1000 Fixture units for Group Venting
*140 Fixture units for Stack Venting
*.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
POLYSTYRENE PACKAGING TOP FOR INSULATION
The Mini-Vent as supplied can beinstalled on 3 different sizes of PVC DWV pipes:
*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
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.
The Maxi-Vent as supplied can beinstalled on 2 different sizes of PVC DWV pipes:
*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
This entire rig was vented by just 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
Note the connection of the AAV within the cupboard rather than extending the pipe through to the ceiling space.
* Common Discharge pipes
Clause 18.104.22.168.2 (b)
Fully Vented Modified
*Refer to Australian National Standards AS/NZS3500.2.2003
Minimum Determined Airflow Capacity of Air Admittance Valves When used as a Trap or Group Vent
Fixture Unit loading of discharge pipe
Min. Airflow capacity of AAV’s
(litres per second)
The maximum capacity:
STUDOR® Mini-Vent™ 7.50 l/s (or 60 FU)
STUDOR® Maxi-Vent™ 32.01 l/s (or 1000 FU)
+ 6 x 1 F.U.(Washbasins)(6FU) = 30 FU
X 2 Floors
Let’s check the next table………..
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
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
When a Maxi-Vent is installed in a roof space, always allow at least 150mm above any insulation
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
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.
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
6.10 PRESSURE ATTENUATORS
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;
(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.
LOCATION OF PRESSURE ATTENUATORS
Note: Where the height of the discharge stack above the base or offset is less than 5 floor levels Clause 22.214.171.124 may apply
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.
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 126.96.36.199 to 188.8.131.52, or pressure attenuators may be installed as specified in Clause 6.10.
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 184.108.40.206.2 (b)
This system is Single Stack Modified
Note: This diagram for demonstrative purposes only.
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