Transcript Slide 1
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, :
1. 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 of 7.5 litres/second at -250 Pa
Airflow of 32 litres/second at -250 Pa
Capacity:
*60 Fixture units for Group Venting
*6 Fixture units for Stack Venting
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
any AAV 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 MaxiVent 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
OUTER SLEEVE
MINI/MAXI-VENT
ADAPTER
POLYSTYRENE
PACKAGING
BOTTOM
Installation
The Mini-Vent as supplied can be installed 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 in Australia
(and basins etc in New Zealand)
*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 be installed on
2 different sizes of PVC DWV pipes:
* 80mm
* 100mm
*When used as a group vent the Maxi-Vent
can also be installed up to1000mm (1 metre)
below the rim/flood level of the highest fixture
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
MiniVents
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
•Clause 7.5.3 and 7.5.7.5.3(b)
•Alternative
Position
Clause 7.5.7.5.2 (b)
* Common
Discharge
pipes
•Clause 7.5.7.2(a)
Fully
Vented
Modified
Clause 7.5.3.
•Clause 7.5.7.5. 2
*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)
* Refer to
Australian
National
Standards
AS/NZS
3500.2.2003
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
stack
1
2
4
6
10
12
15
20
25
30
40
60
80
100
200
300
400
500
600
1000
Minimum determined air flow
capacity of AAV, Litres per second
3
4
6
7
9
10
11
13
15
16
18
23
26
29
41
51
58
65
72
92
Stack Venting
STUDOR Maxi-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™
Note
Traditionally
A stack
the saving
and
ofgroup
unnecessary
Vented
vented
vent
plumbing
plumbing
piping/fire
collars
system
system
etc
using
and
Studor
no roof
AAV’s
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)
6.10.3 Location
•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.
Relief Venting (cont.)
TABLE 6.8
LOCATION OF PRESSURE ATTENUATORS
Number of floor levels served
by the Stack above the base or
offset
Location
3 to 8 floors
One at the base of the stack
9 to 15 floors
One at the base of the stack plus one at mid level of
the stack
16 to 25 floors
One at the base plus one at intervals not exceeding 5
floors
26 to 50 floors
Two at the base of the stack plus one not exceeding 3
floors up to level 25 and at intervals not exceeding 5
floors above level 25
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
•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
Relief Venting (cont)
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.
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
STUDOR Australia 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 teachers nationally
STUDOR would also like to acknowledge the continued support offered by
Plumbers Supplies Co-operative who provided the materials for this project