Pump sounds pretty bad when restricting flow

[phalogore]

Hi. I'm doing some cleaning/test runs in my new setup and when I start to close the outlet valve that I have open to restrict flow, my 1/2hp pump starts to make a loud noise, like it's working waaay harder than it should.
Should I worry about it? It just doesn't sound right, but maybe it's normal since I've never worked with a pump before.

Sorry about the photo, it's the only one I have right now to show you what the pump looks like. I'll take a better one tomorrow.

 

[sandyeggoxj]

Details on the pump would be good. Is it designed to throttle flow? Mag coupling or vfd?

 

[Dan]

+1 on the above post.

Why would restricting the outflow make your pump work harder?

The only thing I can think of is the pump output is some sort of direct drive and dependent on an unrestricted flow and restricting the flow is hindering the pumps efficiency.

The noise could just be coming from the pump pushing harder that it is suppose to or maybe air getting into the pump somehow and bringing it close to cavitation..

Im talking out my arse. What is the name of the pump?

Subscribed.

 

[phalogore]

I took some photos today and apparently it's a Mexican pump, the reference is Aqua Pak Fix 15e, but I can't find any information if it's designed to throttle flow or if it has mag coupling.

 

[LandoLincoln]

That doesn't look like a magnetic coupling pump.

 

[sandyeggoxj]

I am no expert, but it looks like you will need to control flow in that bad boy through electronics. Maybe pwm or something of the like.

 

[LordUlrich]

It looks a lot like the pumps I used in the big brewery where I worked. They are direct drive. You can control the flow a bit with a valve but not like you can with a march pump.

 

[phalogore]

Took a better look at it, and it is in fact a direct drive pump. The guy that build the equipment said I shouldn't go more than 50% on the valve.
Is there a not that expensive way to control the pump electronically you guys could recommend?

 

[The10mmKid]

To me, it looks like a multistage pump. 2 or 3 stages.
Besides electronics, you could plumb in a bypass.

If the output is always more than you need, hard plumb a 1/4" or 3/8" line from the outlet back to the inlet.

If you need the full flow sometimes, plumb in a full size 3-way valve. Again, back to the inlet.

That's a lot of pump that can provide 54M of head. (175ft)

If you find more details on the pump, you may be able to work with the impellers. Maybe remove or block a stage.

'da Kid