Any plumbers on the board?

dang

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I have what I think is a water flow problem at my building. Two buildings on two adjacent properties getting the same city water with each having it's own back flow preventer valves. One building has great pressure and flow but the other one is really bad. I'm going to pick up a pressure tester for the faucet today because it seems like the pressure might be okay, not sure. When you first turn on the water it comes out fairly strong, then immediately slows down to a weak flow. The line that enters the building from the street has low flow so it has to be in the back flow preventer valves or regulators at the street. This is the part that I'm familiar with.

Is there anyone here familiar with these valves and have any ideas? I'm searching online for help/diagrams/explanations but thought I'd ask here too.

The fallback plan is to call the city but I'd like to get somewhat educated with what's going on before I call. And of course they also charge you for showing up and/or fixing it.

Dan
 

m5bb

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There should be a pressure reducer somewhere between the city line and your building. Not as familiar with commercial but those back flow valves you mentioned may also have a pressure reducer. The scenario you described sounds exactly like a pressure reducer valve problem. Comes on normal and then reduces pressure. Colder weather is known to get those guys acting up. Lots of homes in my area recently with the same problem. Good luck!

BTW I'm not a certified plumber. Just a know it all. LOL
 

Markos

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There should be a pressure reducer somewhere between the city line and your building. Not as familiar with commercial but those back flow valves you mentioned may also have a pressure reducer. The scenario you described sounds exactly like a pressure reducer valve problem. Comes on normal and then reduces pressure. Colder weather is known to get those guys acting up. Lots of homes in my area recently with the same problem. Good luck!

BTW I'm not a certified plumber. Just a know it all. LOL

The reducer should be at the meter. Everything from the meter to your house is covered by the property owner. I'm not sure about the back flow valve. My house doesn't have one, certainly not after the meter. In fact you can see the meter flow forward and back. The water "main" coming into my house (post meter) is about 1" in diameter. Most people assume that they are larger. I repaired my old one about 5 times before my neighbor and I bought 700' of 1" pex and replaced the whole run to both of our homes. Not a certified plumber either, but I pretend to be one at home.
 

dang

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Mine is setup very similar to this one and if I remember correctly there is a pressure regulator with this assembly. Like i said though, if you have a pistol nozzle on a hose you can turn it on fast to full and the water shoots 20ft, then immediately goes to about 5ft. I guess it could be the pressure valve but I'm leaning more toward the back flow valve.

back flow valve.jpg


backflow-prevention.jpg
 
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