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Chris Lewis Chris Lewis is offline
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Default How much PSI can this pump produce?

According to Stuart Benoff :

I'm trying to determine if there is a problem with the pump. When I put
a pressure gauge on the line it reads 14-15 PSI however, this is a
'booster' pump not the mail pool pump. It's designed to send
pressurized water to the pool cleaner. The cleaner requires 20-25 PSI
and recommended a pump of this size. So, I'm trying to determine if the
pump is undersized or whether or not there's a problem with the pump.


The question is whether the booster pump reads 14-15 PSI _with_ the
pool cleaner attached. Does it? Or are you measuring the pressure
without the pool cleaner attached with the pump discharging some other
way? Are you measuring the pressure at the pump or at the cleaner?
Try attaching the cleaner and _then_ see what the PSI is at _both_
the pump and cleaner ends.

[I'm not familiar with the use of pool cleaners working on the
pressure side of the pump. It _may_ also be that your plumbing is
undersized or restricted. In which case, the PSI at the pump
end will be okay, but at the cleaner end it won't be.]

Think of it this way - a device like the pool cleaner needs to be
specified at a specific pressure AND flow rate. Eg: "to operate
properly, this device needs 1GPM or more at a pressure of 15PSI
or more".

Secondly, the plumbing between the two devices matter - it has
to be large enough to permit the GPMs that the cleaner needs
without excessive PSI loss.

Industrial equipment is rated/matched that way. So are, for example,
tools for use with air compressors (eg: "this tool consumes
x CFM at y PSI").

The PSI of the output of a pump varies inversely with the GPM
the outlet is permitting.

Pumps _tend_ to have a given "PSI vs GPM" curve given the
HP rating of the pump. In the middle "design range" (of GPMs),
it's pretty much determined by the HP of the pump.

It's not linear, but at least for the most part, two pumps with
the same HP rating _should_ push just about the same amount of GPMs
at the same PSI as each other.

So, if it's the right HP, it (probably) _should_ work.

But, without knowing the GPM requirements of the cleaner or the expected
GPM vs PSI curve of the pump, it's difficult to be absolutely certain
whether a given combination _should_ work or not, and the best bet is
probably to call the manufacturer[s] (cleaner manufacturer _first_),
explain your situation mentioning model numbers etc, and they should be
able to tell you whether the cleaner or the pump are working in spec or not.

The cleaner manufacturer is probably intimately familiar with the
behaviour of the cleaner with every pump on the market. If they
tell you "we have lots of cleaner customers using that pump
satisfactorily", you _know_ that something's wrong with one
(or both) of the devices. They may tell you that there's
something specifically "odd" about that pump that means it won't
work. Or they may tell you that the plumbing is too small.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.