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benb21601's avatar
benb21601
Explorer
Apr 07, 2014

Water hose diameter

just a quick question on using 1/2 inch diameter water hose vs 5/8 inch. i have always used 5/8" but plan on changing around some plumbing and all i can find that will fit my plan is 1/2". curious if anyone has had issues/ no issues with the smaller diameter. not so much worried about pressure as volume. i think all the internal plumbing is 1/2" or smaller so this shouldn't be an issue, hoping for some first hand experience.

Thanks

17 Replies

  • nomad297 wrote:
    skipnchar wrote:
    Water volume will be determined by the smallest diameter in the system between water source and the faucet.


    This.

    Bruce


    Not necessarily when you factor in the fact that we are also reducing the pressure. Flow is directly related to pressure and the area of the cross section. If we decreased the pressure while keeping the diameter the same, we would decrease the flow, but by increasing the diameter, we may be able to recoup some of that loss.
  • skipnchar wrote:
    Water volume will be determined by the smallest diameter in the system between water source and the faucet.


    This.

    Bruce
  • Water volume will be determined by the smallest diameter in the system between water source and the faucet.
  • down home wrote:
    I have had a one inch water hose. It delivers more flow if your water pressure and flow is high enough.


    Again, the size of the hose won't make a difference if you are hooking up to a standard hosebib/sillcock or boiler drain. Even the 3/4" versions of these valves are restricted to less than 1/2" at the seat. There's nothing you can do about that -- once it is choked down, that's all you're going to get. Now, if you are coming straight off of a 1" pump or other source with a 1" hose with no restrictions from one end to the other, that's a different thing.

    Bruce
  • Won't matter, I think, in an RV. I have had a one inch water hose. It delivers more flow if your water pressure and flow is high enough.
    At the time I had a three stage, five hp peak ten, I think pump in the well. It ran ninety pounds of pressure and a lot of flow. The capacitor went bad and no one could find one to replace it. This about the time everything started coming from China.
    It was labeled fire hose. Largest I've seen in a while is 3/4 from Costco. It's not the quality i want but it does have machined brass ends.
    Water hose for the RV came from Fleet wood store and is 25 ft, 5/8 dia, I think, blue with stainless ends.
  • It really doesn't make a difference in any application because you are never going to come across a full-flow hosebib or boiler drain anyway. They are all choked-down at the seat inside which is never larger than 5/16". The largest washer I have ever put in one of these valves is a #1/2, which is a half-inch in diameter. The seat is always smaller than the washer in a valve. Once it is restricted down, that's all you get. There's no way to get more volume/flow, no matter what size hose you put on it.

    Bruce

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