How many GPM can 3/8 flex carry?

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Jadnashua

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The issue is often not how much it can carry, it is what is the restriction in the pipe while doing it. For typical supply issues, using say copper, the flow rate should be limited to 5fps according to the copper institute on hot water. That's only a couple of gallons/minute. Any more than that, and the restriction would increase the pressure. Note, depending on the design of the hoses, the crimped connector at the end may add further restriction on top of the ID of the hose. They work fine on say a flow restricted faucet.
 

Jadnashua

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Since 3/8" lines are often used for faucets that do not have that large of a flow capacity, and the industry standard calls for about 2gpm on copper max..2.5 times more is probably asking a lot of it. You would notice an increasingly significant pressure drop depending on the length of the hose.

FWIW, short-term max flow verses continuous will affect the overall longevity. Pushing lots of water through a small hose also tends to become noisy.
 

Flapper

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If you connect a 20" flex to about 80 PSI water source, with the other end open, about how much GPM will come out the other end?
 

Terry

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bmdc_tub_a2.jpg


These 3/8" flexes allow very little water to the tub. It takes forever to fill.

bmdc_tub_a1.jpg


Very nice, but very slow filling.
 
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