4
In-Line Valves
The second type of zone valve is an "in-line" valve. It is installed
below ground, preferably in a valve box for ease of maintenance.
A separate backflow preventer is required for backflow protec-
tion. In-line valves are automatic valves.
In-line valves are suitable for sites with all types of elevation
changes. Because of their protected location, in-line valves are
less likely to be tampered with by children or vandals, and less
likely to incur freeze damage than above ground models. An in-
line valve is also suitable for use as a master valve.
In situations where the water is pumped from a lake, well, ditch, or other "dirty" water source, sand
and other debris should be filtered from the line through a filter with a 100 mesh screen. If water sup-
ply is also used as a drinking water source, a separate backflow prevention device is required to pre-
vent potential contamination should fertilizers or toxic chemicals in the water be siphoned backwards
through the lines.
If your water is supplied by a municipal water system, check with your local Rain Bird dealer or
plumbing supplier for the type of backflow prevention device required in your area. For specific infor-
mation about backflow and the types of backflow prevention devices available, please call our toll-
free number. 1-800-RAIN-BIRD, and request a "Backflow Prevention Handbook."
Controller
To Sprinklers
Shutoff
Service
Line from
Street
PVB Valve
Valves
