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Best master valve ?



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    You can use the same type of zone valve that you currently have or even install one with a manual shutoff as well.


    I would probably go with a name brand that specializes in irrigation.

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    locky H (Edited )

    All of my zones valves are anti siphon , but someone said should not use anti siphon valve as master valve ?

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    Brandon Moyer

    I found a link on this PAGE  that explained the criteria to look for very well. 


    What type of valve should be used for a master valve?

    Any electric solenoid valve can be used as a master valve, except for anti-siphon valves. Anti-siphon valves may not be used as master valves. (You should never install an anti-siphon valve in a location where there is another valve downstream of it, if you do it will break the anti-siphon part of the valve.) Many professionals like to use brass valves for master valves due to the higher pressure rating and a general attitude that "if it's brass it must be better". I don't feel that a brass valve is necessary unless you can't find a plastic valve with a high enough pressure rating. Note that the pressure rating of the valve should be at least double the expected water pressure in the irrigation system. So if you have 75 PSI, or 5,2 bars, of water pressure the valve should be rated for at least 150 PSI, or 10,4 bars. If the master valve is installed before the irrigation system filter, then a "contamination-proof", "self-filtering", or "dirty water" valve would be the best type of valve to use as the master valve. These are expensive valves that have a small built-in filter to help protect the valve from dirt, which is a major cause of valve failure. If a valve with a filter is too expensive, a valve featuring a "self-cleaning metering rod" or "self-flushing ports" would be the next best thing. At a minimum the master valve should be equal in quality to the zone control valves. I typically install a filter upstream of the master valve, so most of the time I use the same valve model for the master valve as I use for the zone control valves. If you are designing an irrigation system that uses hydraulically operated zone valves, you will want to use a hydraulic operated master valve rather than an electric solenoid type. Hydraulic operated systems are rare, so if you don't know what I'm talking about it doesn't apply to you!



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    locky H


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    Daniel Badders

    I believe some cities or regions have codes that require antisiphon irrigation valves.  I understand some anti-siphon valves can fail due to pressure spikes typically referred to as "water hammer".  This can arise if air is between the master and sub-zone valves, allows water to flow quickly until the air is compressed or displaced, and then sends a pressure surge back toward the master. 

    In my experience an antisiphon valve works as a master under special conditions.  My experience is limited, so follow my experience at your own risk.  I have had no problem using a standard antisiphon valve as a master where pressure surge was avoided.  I used a 25psi pressure regulator near the master and long compliant tubes such as 1/2 polyethylene irrigation tubing distributing the master supply to small flow drip zone valves.  This was on an 30year dumb irrigation controller and likely triggered the zone valves at essentially the same time as the master with no options or adjustments possible.

    Any concerns, corrections or feedback?

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