Bleeding Zone Valves For Underground Sprinkler System

[George7941]

The system has six zones and I used my small Campell Hausfeld hotdog compressor to blow out water, one zone at a time. Repeated the procedure twice. Not sure if I did an adequate job since only a few sprinkler heads popped up and I did not see any water come out from some of the others.

I opened up the two valve boxes, one of them has four zone valves and the other the remaining two. Not sure of the manufacturer of the zone valves but the valve boxes are Orbit branded.

As seen in the pics, each valve has the Philips headed screw. I assume this is a bleed screw and that I should be opening them to bleed out the remaining water. What puzzles me is that the bleed screw is on top and how could it drain the water in the valve with the water being below the screw? Does each zone has to be pressurized with compressed air for bleeding the zone valves?

The property is not level at all. Some of the sprinklers are above the level of the valve boxes and some are below.

There is also one garden hose valve facing up, as you can see in the pic. I did not try opening it since a lot of dirt could fall in and foul the valve. Should I open this valve?

 

[Danno]

The top cylinders with 2 wires are solenoids. I had similar setup where I would use a garden hose end and a short piece of tubing with a quick connect air fitting for the compressor side. Old washing machine hose iirc. The garden hose end connected to the faucet you see in the picture, build up compressor pressure and release the air into each zone by twisting solenoids half turn left. You fittings should be clean to avoid introducing dirt into the system. Your setup looks to need a good cleaning.

 

[RhondaHonda]

Do you have a pool? Maybe the hose connection is for unregulated flow such as filling a pool in the spring? Sorry, not much help on the rest as I just pay someone to winterize mine. I know they do it all through the backflow and it sprays a lot of mist out of the heads but they use a larger compressor.

 

[mk378]

The Philips screws are used for testing (with water). Cracking the screw open will cause the valve to open and flow water to the sprinklers with out needing to energize the solenoid. When doing this, a small amount of water will come out around the screw, it should drain harmlessly into the pit.

For winterizing, don't use the screws. Pressurize the inlet side with air and use the timer to open one solenoid at a time. If you have a small compressor, removing the farthest or lowest sprinkler head may help the water get out.

 

[George7941]

Thanks, mk378. I have one concern. As I stated. the property is not level at all. If the solenoid valve is the lowest point of a particular zone, any residual water left in the lines after blowing out with an air compressor will all drain back right into the valve and possibly cause it to split open from freezing.
I am going to blow the lines out again, this time with a spare 8 gallon air tank hooked up to augment the 3 gallon compressor tank.

 

[sloinker]

The sprinklers themselves are cheap and easy to replace. I have never lost one due to freezing. The SOV's are another matter. I unscrew the jar and remove the guts and leave the jar top off of the valve. Any residual or expanded frozen water exits there. I reinstall with vaseline lube in the spring. Stopped blowing out my system years ago when I still had to replace valves in the spring.
1) Shut off controller
2) Shut off supply
3) Unscrew the tops of all jar valves and remove internals. Put baggie around jar coil assembly to keep dirt out.

In the spring reverse the procedure using vaseline to lube threads and seals.
Your valves in your distribution box look filthy. Dig out excess soil and pressure wash those filthy valves.
Watch out for black widows. My distribution boxes are always crawling with them. I wear gloves and long sleeves and use a 18" screwdriver to move the spiders and webs out of the way.

 

[George7941]

I am going to call the sprinkler company to come and blow it out with their large compressor. They have been doing it for the last thirty years and there has not been any freeze damage, at least none that I know of.