Pump Pipe Plumbing

[elemental]

why is it so hard to find decent professionals?

the pool guy who put in my new pool pump installed two 90 degree PVC elbows at the suction side of the pump. i did not know until i did some reading later that this is bad practice and will shorten the life of the pump.

how bad is this situation?




what do you all think about installing flex pvc pipe from the return line to the suction side of the pump?

thanks for any input!

 

[CJadamec]

That pump won't care about the 90's in front of the pump because of the strainer basket. The strainer will correct any turbulence in the water caused by plumbing before it gets to the impeller eye. You're plumbing as it sits is fine it also looks like it was done pretty well. No need to change anything.

If I was concerned about anything in that picture it would be that inline puck feeder.

 

[elemental]

thanks for the reply CJadamec!

what's your concern with the inline feeder?

according to this article regarding the 90 degree plumbing:
Primed and Ready | Pools/Spas | WaterShapes



is that not a legitimate concern? i don't know anything.

this article mentions 90 degree pipe into the pump as well:
Why Pool Pumps Overheat — And What You Can Do to Stop It - AQUA Magazine

 

[mas985]

An elbow will restrict flow exactly the same no matter where it is located.

Here is the LinkedIn profile of the so called Hydraulic Expert:

https://www.linkedin.com/in/steve-gutai-16361a10/

I don't see a physics and/or an engineering degree anywhere.

I think he is simply propagating the same myths that have been in the pool industry for years.

 

[CJadamec]

On certain types of pump and in other settings having a 90 on the inlet to the impeller would indeed be a bad thing that article isn't wrong but it also isn't as cut and dry as they have it written.

In this case on your pump that 90 being there will have no effect other than just the fact that its another 90 in the plumbing. The 90 in the plumbing isn't directly into the eye of the impeller. The strainer basket is what feeds water to the impeller and it solves the problems associated which the article you read is referring to. You will see no significant change in system performance if you change the plumbing to the pump.

Other than the constant CYA build up from using pucks and making it very hard to maintain the proper FC/CYA ratio levels the feeder is ok I guess. Also the feeder adds way more restriction to your plumbing that the elbow next to the pump does.

 

[mas985]

On certain types of pump and in other settings having a 90 on the inlet to the impeller would indeed be a bad thing that article isn't wrong but it also isn't as cut and dry as they have it written.

I would argue it is wrong because it shows a pump with a pump basket and in that case, it would not have a significant impact.

 

[CJadamec]

The picture they used and the way they presented the information is wrong or at the very least misleading. In particular as they applied it to pool pumps.

The actual statement that a 90 bend right before a pump can be harmful is actually a true statement in specific situations. I'm speaking more of a traditional pump where the plumbing goes directly to the eye without any basket or diffuser in the way.