Pool Vac & Pump Problem

sjsoldo

Well-known member
Jul 17, 2009
82
Have a Pentair VF pump and a Hayward Poolvac Ultra

The Pool Vac has worked fine for years with regular maintenance. I have changed all the moving parts several times over the years.

I have a Jandy valve and actuator that switches from the skimmer to the Pool Vac at a specified time. At the same time, the pump switches to 25 gpm. At the conclusion of the vacuum cycle, the pump goes back to "filter" mode, and the valve switches the return from the skimmer.

This setup has worked great for several years. However, recently the pump stalls a few moments into the vacuum cycle. It "reboots" and then a few moments later it stalls again. When I check the suction pressure at the end hose to the Pool Vac, it is in the appropriate range.

Why is this happening? Should I get a new pool vac? Can I program the pump out of it? Any suggestions would be greatly appreciated.
 

Dirk

Gold Supporter
TFP Guide
Nov 12, 2017
6,818
Central California
I have virtually the same exact vac setup (but different brand vac). When the pump stalls, are you seeing a flood of air in the pump basket? That might indicate your vac hose has a leak (worn out from the sun, maybe) and the hose fills with air between vac cycles, which causes the pump to lose prime when the vac cycle first starts.
 

Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
19,113
Bedford, TX
S,

Since it worked before, and now does not, let's look at possible problems.

Sounds like to me that the pump is running out of water. This could be because something in your cleaner is not allowing enough water through the cleaner.. Or that you have an air leak that allows the pump to suck in air rather than water. It could be an air leak in the vac hose or the ???

Since you have a VF pump, it could be that the pump does not see the flow it thinks it needs, so it tries to increase the flow but can't due to vac or hose size.

If the pump works fine, sucking through the vac hose, with the vac disconnected, then I would have to assume something in the vac has gone south.

Thanks,

Jim R.
 

sjsoldo

Well-known member
Jul 17, 2009
82
Hmmm....

I have this leaf cannister right before the return on the wall of the pool:

1603044430419.png

It does not fill with air, so there is no air leak distal to that. But let me check the hose from the cannister to the wall if it is leaking.

Also, as a diagnostic maneuver, I am connecting the end of the vacuum hose (that is attached to the pool vac) to an old fashioned vacuum head to see what happens when the cleaning cycle starts. If it still stalls, then the pool vac is not the problem.

Thank you for the input !!!
 

TexasBR

Well-known member
Aug 17, 2020
62
Houston, TX
If the level is a bit low, you could be sucking air through the skimmers. This time of year, water evaporation is surprisingly high where I live. This happened to me just yesterday.
 
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sjsoldo

Well-known member
Jul 17, 2009
82
Turns out the pool vac has nothing to do with it. The bare hose--without pool vac attached--still results in a stall. I will post in the "pumps forum"...
 

sjsoldo

Well-known member
Jul 17, 2009
82
Merged threads - TFP Mod.
Have a Pentair VF pump programmed to use a Pool Vac at a specified time. Have a Jandy valve with actuator that switches to the Pool Vac circuit a few moments after.

Problem is when switches to the Pool Vac circuit, the pump stalls and "reboots" a moment later, then stalls again. The Pool Vac has nothing to do with it because it happens with a bare hose without anything attached at the end. Those hose is not leaking air either (there is a Hayward leaf cannister just before the return to the wall inlet on the side of the pool).

Moreover, when the actuator turns the valve from the skimmer to the Pool Vac circuit the pump stalls too. As most of you know, there is a very brief moment as the valve turns from one circuit to the other where there is no flow into the pump.

Never did this before. What would make the system so sensitive all of a sudden? I think this may have began following a power outage. Would altering the priming settings help?
 
Last edited by a moderator:

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
19,680
Northern NJ
What is your filter pressure? What is your clean filter pressure?

When was the last time you backwashed your DE filter?

What model pump do you have?

Are you running it on RPM or Flow setting?
 

sjsoldo

Well-known member
Jul 17, 2009
82
Filter pressure is about 5 PSI

I don't backwash--I take apart the filter and hose off the DE, last done 3 mos ago. Hard to justify repeating this now if the filter pressure is so low (unless the pressure gauge is faulty). But I am desperately looking for a solution, so I will do it today.

Running on flow setting, 25 GPM

Pentair Pump Model 353014. I replaced the drive assembly 3 years ago.