We share a well with our neighborhood. The neighbors want to install a 2-inch meter on the 3-inch supply line, because the 2-inch meter is less expensive. I think it will decrease the water pressure. They say it won't. Who is right? I don't want to have to pay for this and then have to pay for re-doing it when it causes more problems!

Thank you to those who have responded. It looks like I was right, but the other neighbors went out and bought the 2 inch. Oh well. I guess we will have to buy a pump and tank for ourselves because I doubt relying on gravity to supply enough pressure is going to work any more. I didn't realize it was only $39! Sometimes you love your neighbors, sometimes you don't!

  • 2
    I'm not a fluid dynamics expert, but I'm pretty sure the pressure will stay the same. However, the flow rate will decrease. – Tester101 Sep 8 '14 at 2:19
  • Why do you need a meter on a private well? – Hank Sep 8 '14 at 20:01
  • Be a litle patient - your water pressure may be fine, in which case buying a pum and tank will be wasted money. If you could supply more info about how the system is configured, we might be able to make a more informed guess as to whether it will or won't. If you are getting pressure from a gravity tank, and the meter is on the line filling the tank, there may be no effect at all if the tank is of adequate size, for instance. – Ecnerwal Sep 9 '14 at 16:51

Reducing the pipe diameter from 3" to 2" will not decrease the static pressure in the down stream pipes if all valves are closed and no water is flowing.

The restriction to 2" will cause a decrease in flow rate to the down stream piping assuming that the head pressure in the 3" line in front of the meter stays the same as with the original 3" meter.

If your water usage at any given time is quite a bit less than the flow rate available through the 2" restriction then you will not notice a great decrease in delivered pressure. However if the demand flow rate approaches the capacity of the 2" restriction you will start to see a pressure drop off at the outlets due to the head pressure trying to push more water through the meter than can flow due to the smaller 2" size.

My recommendation - If your pump setup is configured for multi-family service with 3" piping then go with the 3" meter.

| improve this answer | |

It will decrease pressure (when there is water flowing - no effect when water is not flowing) the question being "how much?" The answer will vary with how much water flow there is.

This Company's 3" one is only $39 more than their 2". Max peak flow is 396 .vs. 880 Gallons Per Minute (GPM), and max continuous flow is 220 .vs. 528 GPM - so, how many neighbors, how much flow from the well? If you're supplying 20 houses and the pump only makes 100GPM it's probably not going to make much difference if you use a 2" or 3" meter. If you're supplying 100 neighbors and the pump makes 500 GPM it will - at least with that specific company's meters.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.