Question on VS Pump and SWCG - "No Flow"

[xx_alpha_xx]

Hi Folks,

First time poster here. We are new owners of a 30k gallon SWCG pool. Hayward T-15 cell, and installed a new VS pump (SuperFlo, I believe) towards the end of last year.

I am wondering if there is something either wrong with my plumbing or the flow switch, I find that I need to run the pump between 2800 and 2900 RPM (max is 3450) in order to get a consistent green light and constant SWCG. Lowering to 2600/2700 will sometimes not trigger the dreaded "no flow" light, but inconsistently.

This RPM seems pretty high to me, what should I check?

Thanks in advance!

 

[mknauss]

Welcome to the forum!
I suspect your filter is dirty. Clean your filter and record the clean filter pressure. When it rises by 25% (at a base rpm) clean the filter.
I suggest you read ABC's of Pool Water Chemistry and consider reviewing the entire Pool School eBook.

 

[xx_alpha_xx]

Thanks Marty, I have been a lurker for 3 years so have already read both.

I will backwash and report back. In general what is a typical RPM to trigger the flow switch? Does 2800 seem high?

FYI the pool is "new to me" so it actually is about 10-12 years old. Can't speak as to the plumbing, equipment etc. other than what I have already replaced.

 

[Jimrahbe]

X,

The more items between the pump and the pool, the harder it is to push the water through the plumbing.

As Marty point out a dirty filter can reduce water flow.. So can a heater, a tab feeder, small eyeballs, etc...

Also keep in mind that the SuperFlo has to run at a faster RPM to move the same amount of water as the larger IntelliFlo..

What is the filter pressure when running at 2800?? It does sound a little high to me, but I doubt it is the SWCG or Flow Switch.

Thanks,

Jim R.

 

[xx_alpha_xx]

Well, I cleaned the filter and am now able to run at 2000/2100 RPM without triggering "no flow" - that's a huge improvement

Filter pressure dropped by ~10 PSI - from 30 --> 20 @ 2800 RPM, so I guess I was overdue to clean it. I'll keep an eye and clean when it rises 25% (as per pool school ebook).

Need to review the rest of the equipment and post a picture of the plumbing when I get a chance. One thing I noticed is that there is a 90 degree elbow directly after the flow switch (actually a 90 + 90 to make a square-shaped U). Based on reading the installation manual it sounds like this is not suggested.

Thanks so much for the quick help!

 

[rowiac]

What is your filter pressure at 2000 rpm? For reference, I need to run my SuperFlo VS at 2000 rpm to trigger the flow switch consistently and the pressure is about 11 psi. I've tried lower speeds, but eventually the flow switch will start to cycle on and off, and eventually will stay off after a few hours.

 

[xx_alpha_xx]

Same here, mine is around 10/11 PSI at 2000 RPM (after cleaning)

 

[Jimrahbe]

X,

For reference, I run my pump at 1200 RPM and my filter pressure is about 1 or 2 lbs and my flow switch is closed... this is because I have a very simple pool, no heater, etc..

The point being that higher filter pressure means that it takes a lot more effort to force water back to your pool...

Show us some pics of your equipment pad and fill in you pool's signature so that we know all about your pool and equipment.

Do you have a spa? Does it have a constant spillover? What size eyeballs do you have in your pool returns?

Thanks,

Jim R.

 

[rowiac]

X,

For reference, I run my pump at 1200 RPM and my filter pressure is about 1 or 2 lbs and my flow switch is closed... this is because I have a very simple pool, no heater, etc..

I wish I could run my SWCG at that low of speed to save on electricity use. The problem is that I have a very slow buildup of air in the pump over time that eventually migrates to the SWCG and shuts off the internal flow sensor. This must be due to a small suction side air leak that I haven't been able to find. Instead I use a higher speed (3000 rpm) in the morning for priming and skimming for an hour and then switch to 2000 rpm for the rest of the time to generate chlorine. (10.5 hours with weather in the 90s and 100s)

 

[mknauss]

Superflo VS pumps will have to run at a higher RPM (and thus use more electricity) than an Intelliflo VS for the same flow rate.