What is a double check valve assembly?
A double check valve or double check assembly (DCA) is a backflow prevention device designed to protect water supplies from contamination.
When should a double check valve be used?
In any case, we’d recommend double check valves for appliances that use hot water, cleaning products or chemicals – and that includes swimming pools for anyone lucky enough to have one!
What is the difference between a dual check valve and a double check valve?
The difference between a dual check valve and a double check valve is that the double check valve can be tested and repaired with replacement parts while the dual check valve has no provision for testing.
Where do you put a double check valve?
The Double Check Valve must be installed prior to the irrigation system and after the water meter. 2.1. Place the Double Check Valve within 2 feet of the meter box, (See note 5.1 below).
How long does a double check valve last?
Dual Check Valve – This is the most common method of protection. The backflow devices are considered “non-testable” and the only required maintenance is rebuild or replacement of the device once every five years.
Does outside tap need double check valve?
A double check valve is required at the incoming supply and on any outside tap (because of the risk of back contamination from a hose etc into the potable supply).
What is the purpose of a two way check valve?
A two-way check valve allows the source applying the higher pressure to shift the shuttle so that the higher pressure will be directed to the delivery port. With this piping arrangement, the vehicle can have a failure in either circuit without the spring brakes applying auto matically.
Can I have 2 check valves on sump pump?
So with two check valves in parallel, you protect against the stuck-closed scenario (as it is unlikely that both check valves will fail in the same manner), but are actually more likely to have a stuck-open fault, since if either check valve fails open the discharge water can flow back into the sump well.
Do you need to fit a double check valve?
Where should a check valve be installed?
The check valve must be installed at the outlet of the pump and in front of the outlet control valve for maintenance. Generally, the first outlet of the pump is the soft connection (shock absorber), the next is the check valve, and then the block valve.
Do backflow preventers wear out?
Replacing a Backflow Device? A. Backflow devices have internal moving parts and therefore they will eventually wear out and need repairs or replacing.
Double Check Valve Assemblies Designed for use in non-health hazard cross-connections and continuous pressure applications subject to backpressure or backsiphonage incidents, such as lawn sprinklers, fire sprinkler lines, commercial pools, tanks and vats, and food cookers. Have a question or two?
How do you dry fit a double check valve?
Examine the double check valve assembly to determine which end is inlet and which is outlet. It should be stamped with arrows. Do not proceed until certain. Find the clearance from the interior of the valve box to the first fitting. Dry fit the assembly, unions, hose bib tee, and all connecting pipe.
How do you replace a double check valve on a boiler?
Replacing the entire double check valve assembly with a new one is a fairly simple process. Disconnect the assembly section at the unions, and duplicate the section using a new double check valve assembly, pipe, and fittings. Then reconnect, test for leaks, and call for inspection if required.
Can You reactivate a double check valve in the spring?
If the double check valve assembly is indoors, make sure access is still clear when the system is reactivated in the spring. Have the assembly tested and inspected in accordance with local code. Scheduling inspections just before reactivating the system in the spring will get the season off to a good start.