Specification

AS BUILT "RELAXED"
VACUUM
(siphon)
AIR AIR
BACK SIPHONAGE
Flexible synthetic rubber
diaphragm, clamped at
outer edge.
Cross slits through center
open to allow water to
pass through.
Air port valve closed
Spring plunger, depressed
by water flow, directs
outlet stream
Diaphragm open
Diaphragm closed
Air port valve open
Spring plunger assists
valve closure
WATER FLOW CONDITION
SIPHON CONDITION
(a)
(b)
(d)
Figure 1
(c)
DRAIN SLOT
TECH-NOTE
OPERATING INSTRUCTIONS FOR MODEL 34HD
PROCEDURE:
1) During normal usage the Vacuum Breaker must be
turned clockwise hand tight to a seated position. See
figure 1a.
2) The faucet with the Vacuum Breaker installed, may be
operated with or without a hose attached. See figure 1b.
3) When the Vacuum Breaker is installed on a frost-proof
faucet and freezing temperatures occur, shut off the
water and turn the Vacuum Breaker counter-clockwise
until it starts draining, approximately 3 turns. Water will
drain out of the faucet through the drain slots provided in
the Backflow Preventer. See figure 1c
4) After the frost proof faucet has stopped draining, turn
the Vacuum Breaker Clockwise hand tight back to a
seated position. See figure 1d. The faucet is now
protected from freeze damage.
NOTE:
The Vacuum Breaker must be tightly seated on all
faucets in order to function properly. When freezing
temperatures occur, manual draining of frost-proof
faucets must be done to prevent freezing of the faucet
and possible damage. This manual draining is achieved
by turning the Vacuum Breaker as described above
04/10 Rev 2
For more information contact…
WOODFORD MANUFACTURING COMPANY, LLC.
2121 Waynoka Road, Colorado Springs, Colorado 80915 • Phone: [phone]
To view our complete product line visit: www.woodfordmfg.com or email: [e-mail]