How To Select An Irrigation Valve
These devices are used to turn a sprinkler system either on or off. Though manual valves are available, most modern systems include valves that are connected to a controller for automatic operation. SprinklerWarehouse.com offers three different types of control valves: a globe valve, an angle valve, and an anti-siphon valve.
IMPORTANT: A BACKFLOW PREVENTER MUST BE BOUGHT OR PROVIDED SEPARATELY TO COMPLETE THE PROPER INSTALLATION OF A GLOBE OR ANGLE VALVE. IF YOU PURCHASE AN ANTI-SIPHON VALVE, THE BACKFLOW PREVENTER IS ALREADY BUILT-IN AND AN ADDITIONAL ONE IS NOT NECESSARY.
These should be installed adjacent to your point of connection with the water supply. Its purpose is to enable you to operate on the mainline or irrigation valves without disrupting the supply of water to your home. There are two basic types for you to choose from: The Gate Valve and The Ball Valve. The Ball Valve is more expensive, but it typically lasts for longer periods of time.
Commonly purchased for use in commercial irrigation systems. It is typically installed beneath the ground, and to your convenience, is available in almost any size. They are relatively cheaper than the angle and anti-siphon valves. A backflow preventer MUST be bought or provided separately.
Offers the same features as the aforementioned Globe Valve but is constructed with an additional inlet at the base of the valve. This creates a 90-degree angle between the inlet and outlet pipes, a construction that moderates the pressure drop that may occur across the valve. If this is indeed a concern for you, the angle valve is a better choice than the globe valve. Again, a backflow preventer MUST be bought or provided separately.
This is quickly becoming the most popular choice amongst consumers, especially since some building codes are beginning to require their installation in irrigation systems. The function of this particular item is best explained by describing the problem it solves: -The Siphon Effect-. The backflow preventer is already built in.
Dirty Water Application Valves
If you’re working on sites where the primary water source is lakes, ponds, streams or effluent, it’s very likely that you deal with “dirty” water. Since the dirt and debris from this kind of water can choke an irrigation system, picking the right equipment is vital and nowhere is this more vital than in the selection of the correct remote-control valves.
When you select a remote-control valve for a dirty water application, make sure it has filtration features incorporated into the valve by the manufacturer. This is a very important , because not all valves have filters and the area on top of the valve diaphragm and the solenoid area is extremely susceptible to damage from fine particles of dirt and debris. The best method for filtration manufacturers employ to prevent dirt from contaminating the valve and interrupting operation is the “self-flushing” screen.
A filter or screen that is self-flushing prevents water containing dirt and debris from entering the top of the diaphragm and the solenoid. Located on the bottom of a valve’s diaphragm or inserted into the side of the valve body with a tube connected to the base of the solenoid, the screen or filter positioned in the stream of water running through the body of the valve. The water flow continuously flushes the filter screen, dislodging particles and debris before they can accumulate and clog the filter.
One manufacturer’s valve, which is particularly effective in dirty water, is the Rain Bird series of scrubber valves. This series of unique valves have a scrubbing action, which occurs every time the valve is opened and closed. The fingers of the plastic scrubber removes dirt and debris by scraping the stainless steel filter screen clean as it moves up and down with the diaphragm. The action constantly breaks down debris to prevent build-up and clogging.
- If the irrigation system is to be supplied by pumped well or stream water, a strainer should be provided upstream from the backflow prevention device to avoid fouling the valves.
- If the water pressure coming from the meter or pump exceeds 60 psi, it may be necessary to install a pressure reducing valve upstream from the backflow prevention device to reduce water hammer and valve wear. Also consider installing a water hammer arrestor.
- Unless following manufacturer’s instructions to the contrary, always turn valve handles slowly to avoid water hammer.
- Only the manufacturer can honor a warranty. Therefore, manufacturer’s instructions prevail over everything except local authority.
- Installation errors on backflow prevention devices aren’t always obvious, but they’re dangerous. Protect family and neighborhood from waterborne health hazards by paying close attention to installation details.
- PVC pipe and fittings deteriorate in sunlight unless Schedule 80 is used. PVC is also less resistant than copper to damage by lawn equipment or other physical forces. When installing PVC above ground, pay particular attention to providing a well-built shelter.