Durgo Air Admittance Valves

How the Air Admittance Valve worksThe task of sewage system venting is to admit

air into the system in order to break the vacuum

when discharge or drainage of a fixture creates

negative pressure flows through the pipes.

These vacuums may otherwise empty the traps

Venting to atmosphereAn open vent pipe is needed to discharge the

air drawn in through the Air Admittance Valves

and to eliminate any possible positive pressure

in the DWV system. It is also necessary to vent

at least one vent to atmosphere in certain

jurisdictions to faciliate the entire DWV system.

Closed valveOpen valve

In single-family housing developments, every

tenth house is usually equipped with an open vent

pipe located downstream. Since no cold air flowing

through the end of the sewer pipe, the risk of

freezing is reduced in shallow runs of pipe.

and allow foul air to escapefrom the DWV

(Drainage Waste Vent) leaking foul odors indoors.

Durgo Air Admittance Valves open in the event

of a vacuum and admits air into the sewer system.

The valve is otherwise closed and is perfectly tight.

Installations in Multi-family

apartment buildings

· Use a larger size of the horizontal sewer

main also at the bend and for a short

distance up the riser.

· Use a larger size of the horizontal sewer

main and bend.

· Install a separate riser for the lower

floors of the building.

Secondary ventingSecondary venting is used for increasing the

capacity and/or reducing the size of the

horizontal sewer branch. It is important for the

whole of the horizontal branch to be flushed

Forewarning of blockageDurgo Air admittance Valves also provides warning of incipient blockage

of the sewer system. This warning is provided by the water level in the

WC bowl remaining higher than after a normal flushing, and by the slow

drainage of fixtures upstream from the blockage. This warning enables

preventive measures to be taken prior to complete blockage and owerflow

of fixtures.

with liquid. There must be at leastone drain unit

outside the vent pipe connection. Clogging of

the connection could otherwise occur.

A possible problem in apartment buildings is that liquid plugs may form at

the transition from the riser to the horizontal sewer main. This may cause

odours to be forced up through the traps. This problem may occur regardless

of wether the top of the riser is open or fitted with a

valve. This can be avoided by taking one or more

of the following measures:

Sizes and dimensionsDurgo Air Admittance Valves are also produced in number of special

sizes. A number of these various sizes are intended for international

markets. Others are intended for solving problems in obsolete installations.

Part no. Connection. mm

3131547 15-½" threaded.

3131548 20-¾" threaded.

3131554 25-1" threaded.

3131562 32

32,6 adapter

3131570 40

42,6 adapter

3131572 40-1½" threaded. Junior

JIS-40 40-1½" threaded. Senior

3131571 48

313US05 50 with 40 mm cap.

3131505 50

3131505B 55,9 adapter

JIS-50 60

3131513 75

JIS-65 76

3131513B 88,9

3131521 90

3131521A 100

3131539 110

JIS-100 113

JIS-125 140

160 adapter

JAPAN

USA

GERM

ANY

UK

FRANCE

HOLLAND

AUSTRIA

ITALY

DENM

ARK

SW

EDEN

NORWAY

FIN

LAND

CHIN

A

TAIW

AN

AUSTRALIA

SAUDI ARABIA

In the table, Swedish

standard sizes are shown

in bold typeface.

The original

The launch of the Durgo Air Admittance Valve in 1974 heralded a revolution in

sewage pipework installations worldwide. Air Admittance Valves are now standard,

and the Durgo AAV is unsurpassed in capacity, reliability and quality. The true

beauty of this product is in it's simplicity of design and function, with the body

made of ABS plastic and the seal of EPDM rubber.

PAT 7906706-2

Durgo Air Admittance Valves are 100 % maintenance-free.

Durgo Air Admittance Valves are manufactured in more than 20 sizes. High-rise

buildings or single family homes, large or small, there is always a Durgo AAV

suitable for the job. Reliable proof of quality is that Durgo AAV's have been

specified for millions of installations worldwide.

Du

rgo

AB

20

07

03

28

EN