I dont know What backflow preventer to buy

I was wondering if i need a backflow with a vent or not the old one was leaking and i suggested we replace it everything is old and everyone is always trying to save but i like the comfort of new stuff but i thought the bfp was dirty or maybe a washer inside im no expert with them but do i need a vented bfp.

What type of application are you using it for? If the existing one is a RPZ (vented device) then chances are it should be replaced with the same device. Most commercial properties require vented devices. The type of device is dependent on the severity of the risk to backflow.

John

rebuild it.

It depends on what the application is. Most BFPs and ALL vacuum breakers have a "vent" of some kind. But whether you can use an atmospheric one, a "pressure vacuum breaker", a "double check", or need an RPPBFP depends on the local requirements as well a the application.

hj said:

It depends on what the application is. Most BFPs and ALL vacuum breakers have a "vent" of some kind. But whether you can use an atmospheric one, a "pressure vacuum breaker", a "double check", or need an RPPBFP depends on the local requirements as well a the application.

Click to expand...

There is no vent on a DBL check.

John

A double check is NOT a vacuum breaker, but the Watts 9D double check DOES have a vent on it. And I did say "most", not "all" double checks, since fire sprinkler systems use unvented double check valves.

The Watts 9d is not a DBL check it is a daul check, which in my area is not allowed as it can't be tested.

John

At this point we don't know enough to be much help. Need to know what the application is. Somehow we are focusing on a Watts 9D but I have not read anything from the OP that confirms that. Generally though, if it is a backflow preventer, most of them can be rebuilt fairly inexpensivly however, before rebuilding or replacing it would be a good idea to find out if the device is just doing it's job. Probably 80% or better of the BFP and RPZ devices that we are called on to repair/replace are leaking because there is a backflow situation. The other thing to keep in mind is that if you rebuild the BFP without the proper test equipment you have no idea if you have done the job right or solved the issue.

quote; Watts 9d is not a DBL check it is a daul check

In my dictionary and thesaurus, DUAL, (not daul), MEANS "two" which is a synonym for double. We have absolutely NO IDEA what make or model BFP they are referring to. Here, the 9D is frequently used for the water supply to swimming pools.

Double checks : http://www.watts.com/pages/_products_sub.asp?catId=65&parCat=93

Dual checks: http://www.watts.com/pages/_products_sub.asp?catId=65&parCat=95

Thanks Jimbo, you saved me the trouble.

Anyone having backlow questions should log on to watts.com and peruse the literature and training videos they have there.