how to test pump pressure?

[douggiestyle]

my first guess would be to hook the pump up to a hose and see how high you can raise the output of the hose and still have flow. then use the height that the hose was raised to and formulate the pressure of the output. if so how would you calculate this or is there some table.

i could also be completely off track, any other suggestions?

 

[mpomfret]

Home Depot sells a pressure guage for measuring faucet output pressure. They have a standard hose connection, so you would have to make an adapter to connect to your pump. They are in the aisle with the sprinkler system stuff. I'm not sure if the measurement range of the guage would cover the pump pressure, though.

Matt

 

[douggiestyle]

i thought of that (my local hardware store loaned me theirs when i had a pressure problem in my house) i thought that it would be the wrong scale.

 

[mpomfret]

I did a Yahoo search on "convert inches of water to psi" and came up with this link: http://home.mchsi.com/~gweidner/pressure-conversions.pdf#search='convert%20inches%20of%20water%20to%20psi' This sounds like what you were getting at. I haven't read through all of the info, but maybe it's enough of a lead to get you there.

 

[BruiseAndy]

29" ish of water equals 1psi. Your hose idea sounds best/cheapest.

 

[BeanAnimal]

The standard way to test a pumps output pressure is to deadhead it with a gauge. Water at 62F exerts 0.433 PSI per foot of head.

The basic procedure would be to deadhead the pump and read your pressure gauge. Divide the P.S.I reading by .433 to find the feet of head.

You may want to grab a glycerin filled gauge as a cheapy air filled unit will likely bounce to sharply to get a decent reading.

You can also get a more stable needled by placing the gauge further from the pump outlet. Be sure to use rigid pipe so that there is no oscillation that will affect your readings.

 

[douggiestyle]

i wish to know the pressure for using an eductor.
i think ill go with both. hose and gauge. and post the results.

didnt think of the inches of water. but yeah.

 

[douggiestyle]

<a href=showthread.php?s=&postid=6637832#post6637832 target=_blank>Originally posted</a> by BruiseAndy
29" ish of water equals 1psi. Your hose idea sounds best/cheapest.

that works out to be about right according the table link above

inches of water * 0.03613 = psi

29 * 0.03613 = 1.048 psi