Pool losing prime

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Rod1971

Pool losing prime

Postby Rod1971 » Sat 26 Aug, 2017 20:29

My pool is running perfectly for about 2 days and then loses prime. The pressure will start off at about 20. It will stay there for a little and then ]over the next day or so will move down to 15. No visible signs of air in the system. It will stay at 15ish for about half a day and then move down to 10. At this point I will see air in the pump filter. Then it will eventually lose prime. If I shut off the pump and either open the pump filter releasing the pressure or I backwash the pool will prime right back up and last another couple days. I can't find any suction leaks. I spoke to my pool guy and he said more than likely your sand is bad in your filter. Does that make any sense? Any help or comments would be appreciated.

Thanks!!!


Denniswiseman
Pool Industry Leader
Pool Industry Leader
Posts: 2592
Joined: Tue 06 Sep, 2011 05:48
My Pool: 10k inground fibreglass, Telescopic Cover, Hayward Powerline pump, Quality filter with glass media, 27kw output heat pump, K-2006C test kit
Location: United Kingdom

Re: Pool losing prime

Postby Denniswiseman » Sun 27 Aug, 2017 01:51

Rod1971 wrote:My pool is running perfectly for about 2 days and then loses prime. The pressure will start off at about 20. It will stay there for a little and then ]over the next day or so will move down to 15. No visible signs of air in the system. It will stay at 15ish for about half a day and then move down to 10. At this point I will see air in the pump filter. Then it will eventually lose prime. If I shut off the pump and either open the pump filter releasing the pressure or I backwash the pool will prime right back up and last another couple days. I can't find any suction leaks. I spoke to my pool guy and he said more than likely your sand is bad in your filter. Does that make any sense? Any help or comments would be appreciated.

Thanks!!!

It definately seems like a small suction side air leak. Have you lubricated your pump basket "O" ring with silicone grease
Have you tried raising your pool level so that it's 2/3 the way up your skimmer opening
Sand doesn't go bad, it's been around for millions of years, what you could do is Deep Clean your filter to eliminate it from the equation
Rod1971

Re: Pool losing prime

Postby Rod1971 » Sun 27 Aug, 2017 17:34

The O ring has been replaced and lubed and the water level is plenty high. In an attempt to determine if the filter/sand is the culprit I have been running it for 24 hrs on recirculate. The pressure started 18 and and soon leveled out at 16. Another day or so and I should know.

On a side note, I recently replaced the spider gasket and top of the Hayward multivalve. When replacing it I noticed that some of the groves in the valve body were pretty wide and a little chunk was out of one of the side just below and up to the gasket. I epoxyed that and put some sealant in the groves. Seems to be working ok as I don't hear any water draining thru the backwash like I did before when it was on filter. There is a very slight drip from the backwash where the pipe connects to the valve. Could this deteriating valve have anything to do with my pressure loss over a couple days? I ruled it out as it is passed the suction side and figured at most it would drip water and I am not noticing anything around the edge or handle. I think I had my pressure issue around then but not sure it was to this extent.

Any thoughts are appreciated.

Thanks
Denniswiseman
Pool Industry Leader
Pool Industry Leader
Posts: 2592
Joined: Tue 06 Sep, 2011 05:48
My Pool: 10k inground fibreglass, Telescopic Cover, Hayward Powerline pump, Quality filter with glass media, 27kw output heat pump, K-2006C test kit
Location: United Kingdom

Re: Pool losing prime

Postby Denniswiseman » Mon 28 Aug, 2017 03:52

When running on recirculate you are bypassing the filter and have no resistance and no problems unless you connect the vacuum as this puts an extra suction load on the pump
The MPV is always under pressure, even if there was a problem inside you shouldn't be getting air in your pump basket
You could try connecting a vacuum hose both on recirculate and filter and see if that creates air in the pump basket
Normally the only problem with a filter is higher pressure as the dirt builds up and creates more resistance to flow through it. The fact that your pressure is dropping comes back to the pump suction. Remember pump outlet positive pressure, pump inlet negative pressure
Replacing filter sand is a big job and unnecessary (i've been there) but as previously mentioned a filter Deep Clean would be beneficial but would probably lower your clean pressure to start with
Bladeski44
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I'm new here
Posts: 3
Joined: Sun 29 Nov, 2020 12:23
My Pool: Shaped like a thought bubble about 17,000 gallons with 7 foot deep end. Jandy filter and Intelliflo2 pump and Hayward vacuum sweeper.

Re: Pool losing prime

Postby Bladeski44 » Sun 29 Nov, 2020 12:32

Hey Dennis...I've seen you mention "side suction". What is a good example? With vacuum the PSI is a beautiful 8. However, I just manually cleaned filters when PSI was running about 17 and after that, at first turn on afterwards, I had that 8 PSI with vacuum and now it's a steady 4 PSI is that loo low? Hoses are fine but I do see many bubbles in pump basket area when running at 3150, just fine (no bubbles) at 2200 (is it RPM?). If it works perfectly without vacuum, the problem has to be from the skimmer back to the sweeper right? The sweeper has a loose nozzle on top where I connect the hose. Even though I have this problem (I think 4 PSI is a problem anyway :oops: ), I've learned a lot from you.
Denniswiseman
Pool Industry Leader
Pool Industry Leader
Posts: 2592
Joined: Tue 06 Sep, 2011 05:48
My Pool: 10k inground fibreglass, Telescopic Cover, Hayward Powerline pump, Quality filter with glass media, 27kw output heat pump, K-2006C test kit
Location: United Kingdom

Re: Pool losing prime

Postby Denniswiseman » Sun 29 Nov, 2020 17:49

Air in the pump basket is a suction side air leak and can be anywhere from the pump to the skimmer and polaris, bearing in mind the vacuum puts an extra load on the suction and can cause a small leak to be more noticable
The vacuum hose and polaris are covered in water and shouldn't allow any air leak
3150 and 2200 is RPM
Is the 4 PSI at the lower speed
It may creep up again
Bladeski44
I'm new here
I'm new here
Posts: 3
Joined: Sun 29 Nov, 2020 12:23
My Pool: Shaped like a thought bubble about 17,000 gallons with 7 foot deep end. Jandy filter and Intelliflo2 pump and Hayward vacuum sweeper.

Re: Pool losing prime

Postby Bladeski44 » Mon 30 Nov, 2020 08:28

The 4 PSI is at lower AND higher speed. Can I go with a 4 PSI as ok for now with the vacuum-it is the lowest point and it surely seems to be working normally. :clap: Thanks D.
Denniswiseman
Pool Industry Leader
Pool Industry Leader
Posts: 2592
Joined: Tue 06 Sep, 2011 05:48
My Pool: 10k inground fibreglass, Telescopic Cover, Hayward Powerline pump, Quality filter with glass media, 27kw output heat pump, K-2006C test kit
Location: United Kingdom

Re: Pool losing prime

Postby Denniswiseman » Mon 30 Nov, 2020 10:24

Low pressure isn't a problem unless you find your filtration isn't as good as it should be
Just leave it and see if it builds upas the ssnd gets a bit dirtier
Teapot
Pool Industry Leader
Pool Industry Leader
Posts: 1337
Joined: Tue 17 Oct, 2017 10:52
My Pool: 12 x 24 (45m3) liner pool, Triton TR60 filter with AFM glass media (Activate) and variable speed pump running 0.08HP
Location: UK

Re: Pool losing prime

Postby Teapot » Mon 30 Nov, 2020 12:25

Is the gauge any good? Surprised to hear you get the same 4psi at both speeds.
Bladeski44
I'm new here
I'm new here
Posts: 3
Joined: Sun 29 Nov, 2020 12:23
My Pool: Shaped like a thought bubble about 17,000 gallons with 7 foot deep end. Jandy filter and Intelliflo2 pump and Hayward vacuum sweeper.

Re: Pool losing prime

Postby Bladeski44 » Mon 30 Nov, 2020 15:33

I'd now say AROUND same PSI at both speeds when using vacuum, between 4 and possibly 5PSI...but sure it bumps up when not using vacuum, from 8PSI at 2550 to about 9PSI at 3150. I was hoping after I just cleaned the crap out of those filters that 4PSI wasn't too low-sounds like D and Tea might go along with me on that. That's what I'm going with, thank you guys.
Teapot
Pool Industry Leader
Pool Industry Leader
Posts: 1337
Joined: Tue 17 Oct, 2017 10:52
My Pool: 12 x 24 (45m3) liner pool, Triton TR60 filter with AFM glass media (Activate) and variable speed pump running 0.08HP
Location: UK

Re: Pool losing prime

Postby Teapot » Mon 30 Nov, 2020 19:03

Whilst I am not sure you dont have a problem, my pool runs a pressure of 0.6 psi but flows sufficient water to turnover the pool 4 times in 24hours. The water is amazing in clarity not far off tap water clarity, measured via a digital turbidity tester.

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