Sprinkler System Backflow Preventer

[johne023]

Tried to winterize my sprinkler system. Couldn't find the main shut off valve that is usually just a few feet from the water meter. Talked to the builder and he said there wasn't a shut off valve between the meter and sprinkler system that it flows directly to the backflow preventer. I opened the ball valves on the backflow preventer and neither had anything come out. I haven't run the sprinkler system in a few weeks. I thought code for the backflow preventer was that it had to be hooked up to the main waterline before going to the sprinkler system. I turned on every station and when the stations are turned on water shoots out of the ball valves. So it seems to me that the backflow preventer isn't actually preventing any backflow to the main water supply and was just put there to pass inspection. Is this up to code or something that needs to be fixed? House was built this year didn't know if I needed to get it taken care of under warranty or if this was an accepted practice.

 

[Gary Swart]

There are federal requirements for back flow prevention, but sadly some states do not pay attention to federal laws. I suspect Oklahoma is one of these. First of all, there should be a master shutoff valve for the entire property in conjunction with the water meter. After that, the irrigation water should tee off the main supply and be controlled by a valve. From there, the back flow prevention device would be installed. That way the irrigation and domestic supplies are separate. Furthermore, the back flow device should be tested by a licensed inspector each year. This to to assure that the inner seals are still holding. Occasionally, the device has to be repaired. Your local water supplier should require this inspection be done. As an example, my city inspects the back flow the first time. Each year after that, they send a list of certified inspectors in the area and the homeowner is responsible for scheduling one of these inspectors to come to the property and test the device. When it is done, the inspector sends a copy of the inspection to the city and gives the homeowner a copy. Cost ranges from $35 to $50 depending on the inspection service hired. In other words, this is taken seriously. This testing is not a DIY job. You need test equipment and certification.

 

[Sponsor]

 

[hj]

Your diagnosis/description does not make any sense, unless you also have a "main" electric valve, ahead of the backflow preventer, that turns on before any zone activates. Gary, your "description" is NOT relevant to every area. In this area, only commercial installations have to be periodically inspected, and the city does not do ANY testing. The initial testing and all subsequent ones are all done by private contractors. The backflow preventer comes WITH its own shutoffs and test cocks so its supply does not have to be "controlled by a separate valve". The utility is responsible for installing a valve ahead of the meter, if they want one, and only a few areas requires a "master" shutoff valve right after the meter, which is what he was looking for.

 

[Wet_Boots]

time to take some photos of the system plumbing and post them