俺贴个俺每年做的PROCEDURE. 俺的SYSTEM 是自己设计自己做的, 一开头就不想没年花
钱请人吹, 在所有的LOW POINT 都有MANUAL DRAIN VALVE. 大多CONTRACTOR 做的
SYSTEM 只考虑INSTALL 时省力, 多半是要请人吹的.
Irrigation System Winterization Procedure
1. Turn the timer to OFF.
2. Shut off the main valve (1” brass ball valve in the 10” well), open
the main line drain valve (½” brass ball valve, in the same well).
3. Open the 4 test cocks on the double check anti backflow.
4. Open the plastic drain valve in the 6” round valve box.
5. Manually open all 7 zone valves by turning the solenoid 1/4 turn
counterclockwise.
6. Remove 7 drain plugs on the zones. Use an adjustable wrench. Sprinkler
zones have ½” plugs. Dripping zones have ¾” plugs. Those
octagon heads have 24mm and 28.7mm sizes. Not easy to find fixed wrenches
this big (fixed wrenches would be easier because of the smaller size in the
cramped space but it doable with adjustable wrenches).
7. As water rushes through the 7 drain plug holes, go around the yard to
open all drain valves at low points. All those valves are ½”
plastic ball valves in 4” wells. Two in front yard: SE and SW corners. Two
in east side yard: SE and SW corners. One in back yard: on north edge, about
10 yard to the west of the cherry tree in the lawn.
8. Lift each sprinkler that has check valve to drain the water in the
sprinkler body. There are four Rainbird 1800-SAM in west side yard: the four
in the south part. Two Hunter PGP with check valve membrane installed: the
two at the lowest points on the north edge. Just lift the heads for few
seconds.
9. When all water stops running from the drains, loosely put back the 7
plugs – just a turn or so to keep them in place to prevent creatures from
getting into the holes.
10. Set all drain valves, and the in/out valves on double check and the
test cocks at 45 degree angle.