User Guide

TESTING
All mechanical devices should be inspected on a regular basis to ensure they are working correctly. The
assembly should be tested at time of initial installation, after servicing or maintenance, and at least annually
thereafter. Acceptable test procedures are published by Foundation for Cross Connection Control and Hydraulic
Research at the University of Southern California (USC), The American Water Works Association (AWWA),
The American Society of Sanitary Engineering (ASSE Series 5000) and the Canadian Standards Association
(CAN/CSA B64•10). Please consult the regulatory authority in your area for more specific information.
FREEZE PROTECTION
The backflow prevention assembly may be subject to damage if the
internal water is allowed to freeze. The unit must be protected from
freezing using a heated enclosure, insulation heat tape, or other
suitable means. The unit must always be accessible for testing and
maintenance. If the system will be shut down during freezing weather,
use the following procedures to drain internal passages.
Ball Valve Shut-Off Draining Procedure
If the assembly has been installed with ball valve shut-off valves, they
must also be properly drained to prevent freeze damage. After draining
procedure has been completed on the backflow prevention assembly,
position all ball valve shut-offs and test cocks in a half open/half closed
(45 degree) position.
Open the ball valve approximately 45 degrees while draining the
pipeline and assembly to allow water between the ball valve and valve
body to drain. Leave the ball valve in this position for the winter to
prevent freeze damage.
The ball valve must be fully closed before the system is repressurized. OPEN AND CLOSE BALL VALVES
SLOWLY TO PREVENT DAMAGE TO THE SYSTEM CAUSED BY WATER HAMMER.
Main Valve Draining Procedure (
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2
" - 2")
1. Close the main shut-off valve.
2. Open the inlet drain.
3. Open the inlet and outlet ball valves 45 degree (half open, half closed).
4. Open all testcocks.
5. Open the outlet drain.
6. Remove the cover and inlet check module until all water inside valve drains back out through inlet drain.
7. If you blowout the piping downstream of the backflow assembly using compressed air: Connect the air
supply to the outlet drain and close the outlet ball valve. After clearing the system with air, partially open
the outlet ball valve. Leave all drain valves, testcocks, and ball valves in half open/half closed position for
the winter.
FEBCO Model 850 / 850U (
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" - 2") Page 9