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Vandalism Protection
Use these guidelines to protect and secure an assembly if the unit is
installed where vandalism may be a problem.
• Remove the shutoff valve handles to discourage tampering.
• Install a protective enclosure over the unit to discourage vandals.
If an enclosure is used, install it so that adequate clearance is
available for maintenance and testing. Consult local codes before
installing any type of protective enclosure.
Freeze Protection
The backflow prevention assembly may be subject to damage if
the internal water is allowed to freeze. Protect the unit from freezing
by using a heated enclosure, insulation heat tape, or other suitable
means. The unit must always be accessible for testing and mainte-
nance. If the system is shut down during freezing weather, use the
following procedures to drain internal passages.
Main Valve Draining
1. Close the main shutoff valve.
2. Open the inlet drain.
3. Open the inlet and outlet ball valves 45 degree (half open/half closed).
4. Open all test cocks.
5. Open the outlet drain.
6. Remove the cover and the inlet check module until all water inside
valve drains back through the inlet drain.
7. If compressed air is used to blow out the piping downstream of
the assembly, complete the following step:
a. Connect the air supply to the outlet drain and close the outlet
ball valve.
b. After clearing the system with air, partially open the outlet ball valve.
c. Leave all drain valves, test cocks, and ball valves in the half
open/half closed position for the winter season.
Ball Valve Shutoff Draining
If the assembly has been installed with ball valve shutoff valves, the
ball valves must also be properly drained to prevent freeze damage.
After the main valve draining procedure has been completed, posi-
tion all ball valve shutoffs and test cocks in a half open/half closed,
45 degree position.
1. Open the ball valve approximately 45 degrees while draining
the pipeline to allow water between the ball valve and valve body
to drain.
2. Leave the ball valve in this position for winter to prevent freeze damage.
OPEN AND CLOSE BALL VALVES SLOWLY TO PREVENT DAMAGE
TO THE SYSTEM CAUSED BY WATER HAMMER.
The ball valve must be fully closed before the system is repressurized.
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