Backflow Valve Question

[cdreed06]

I am going to replace our backflow valve. The one we have is like this -
View attachment 642 Is there anything wrong with replacing it with one like this?
View attachment 643
Thanks!!

 

[I.B. Washincars]

Is there any certain reason you are replacing it? I have one just like that that failed wide open after we lost water pressure. I got a kit and rebuilt it myself. After getting it apart I saw what had stuck and could probably have gotten it unstuck with it in place. There's not much to them and it was pretty simple to work on.

 

[cdreed06]

Thank you IB. I'm replacing it because it leaks and the pressure drop across it is incredible. I hadn't thought much about taking it apart and cleaning it, just afraid of getting it apart and running into trouble and not being able to be open. I guess I could make a piece to go in place of it while repairing it. Thanks for the reply.

 

[JGinther]

Many places require RP type backflow preventers. Replacing one with one that doesn't meet code will make it where they can shut you down the second they see it if they want to. I had one place that only had a vacuum breaker installed since 1965. When the city started requiring backflow preventer inspections and testing, they shut me down for it not being an RP type. I don't think the second one is a reduced pressure zone type. All they consist of is 2 check valves, a diaphragm, and a piston seat, so they are easy to rebuild and would probably be way cheaper than the new one.

 

[cdreed06]

Thank you JGinther, it must be a code issue with the RP one that we have. The builder of our wash would not have spent money on something he didn't absolutely have to have. So I guess I'll try to rebuild it. Thanks to all for the help.

 

[Randy]

Back in the day I was state certified Backflow installer/tester. You need a RPV for a car wash. The lower one pictured is double check assembly, they are normally used on sprinkler systems. I’m not a big fan of Watts RPV, I like the Watkins 975 the best, and they seem to have the fewest problems. A pressure differential of 10 -12 psi is normal. All of them are rebuildable

 

[Greg Pack]

I had to crack open a watts 009 a couple of days ago because it was leaking. Cleaned a little trash on the seat and it was back in service in less than ten minutes. I always think its' best to wait for a rainy day to touch anything that can cause a total wash shutdown though.

 

[Ghetto Wash]

I always think its' best to wait for a rainy day to touch anything that can cause a total wash shutdown though.

That's why I don't touch my backflows. I'm pretty hands on and backflows are the one thing that I won't touch at my washes. The city mandates an annual inspection, and if there is a problem I call the backflow inspection guy and he fixes them. Pretty cheap compared to accidentally shutting my wash down.

 

[cdreed06]

Thank you all, my backflow guy tells me this backflow valve I have cost around $1,000 so I really want to do this myself. The only problems are that it is in a really hard place to reach and it is grown up with scale and looks very ugly. I am going to attempt to clean it on a rainy day. Thanks everybody!