Is my pump to Small for my pool? Pump not priming, Stumped!!!

[earevalo23rd]

hello, in need of help or ideas.

I have a 15 x 30 rectangle pool, approx 13,500 gallons with an elevated spa. My pool equipment
sits roughly about 40-50 ft away from my pool. Pool is about 4 years old.

I recently upgraded my single speed Pentair 2.0 HP Pump to a Jacuzzi - JVS185S 1.85 THP Variable speed pump.
When I purchased the pump, I was aware of the slight drop in horse power but I thought it was negligible and shouldn't be an issue.
Prior to upgrading, I had no issues whatsoever.

Since the install in early February, this pump has never been able to maintain prime. The water sits roughly 2-4 inches below the lid.
The only way I have been able to prime the pump is during backwash, or if I open up my Spa Drain (never had to do this before). And even
then it will only hold prime until the pump shuts off. When it turns back on prime has been lost.

My equipment has been inspected twice by a local pool company, and they have found no cause for this. No leaks at all.

Anybody experience similar issues? Is my pump to small? should I upgrade to a 2.7 HP Pump?

TIA,
Eddie.

 

[ajw22]

Welcome to TFP.

The HP of your pump is not your problem.

You have a suction side air leak. Finding it often takes a bunch of detective work.

Suction Side Air Leaks

If you see air bubbles coming out of the return lines in your pool, you likely have a leak. Some signs that a suction side plumbing leak has occurred include: Read more

www.troublefreepool.com

Post pics of your equipment pad and pump.

 

[ajw22]

 

[MITBeta]

Make sure the gasket on the pump lid is properly lubricated as well.

 

[earevalo23rd]

Welcome to TFP.

The HP of your pump is not your problem.

You have a suction side air leak. Finding it often takes a bunch of detective work.

Suction Side Air Leaks

If you see air bubbles coming out of the return lines in your pool, you likely have a leak. Some signs that a suction side plumbing leak has occurred include: Read more

www.troublefreepool.com

Post pics of your equipment pad and pump.

 

[earevalo23rd]

Equipment has been inspected for air leak by me, several times, and by pool company 2 times. so in your opinion
HP is not the issue?

 

[ajw22]

HP is not the issue?

Nope, a pool really needs less then 1/2 HP in a pump. Most pool pumps are grossly oversized.

You have a plumbing problem in your suction line. Now installing a new pump may fix the plumbing problem just the way installing this pump created the problem. The fix is in the suction plumbing not in changing the pump. Unless something in the Jacuzzi pump body is defective and leaking air into it.

 

[Jimrahbe]

E,

HP is not your issue!!!

When you turn the pump off, does the water in the pump basket stay full or does it drain back into the pool?

If it drains back into the pool, then you have an air leak. It is just like putting your thumb over the end of a straw and pulling it out of a glass of water. The water in the straw will stay there until you take your thumb off of the end of the straw.

You may have more than one problem. I say that because of your comment that your pump will not prime without the spa drain on. As a test, I'd put the Intake and Return valve in the spa mode, with the pump off, and then turn the pump on and see if it primes ok. I'd also shut off the pump, while in the Spa mode, and see if the pump drains down.

Then report back your results.

When was the last time you opened and cleaned your filter?

Thanks,

Jim R.

 

[earevalo23rd]

Nope, a pool really needs less then 1/2 HP in a pump. Most pool pumps are grossly oversized.

You have a plumbing problem in your suction line. Now installing a new pump may fix the plumbing problem just the way installing this pump created the problem. The fix is in the suction plumbing not in changing the pump. Unless something in the Jacuzzi pump body is defective and leaking air into it.

ok. Thanks for your help. Pool company is coming out for a third inspection, they are going to pressure test the lines to see if i have an underground leak. also am in the process of getting the pool pump replaced just in case that is the issue.
ill see how it goes. Thanks.

 

[earevalo23rd]

E,

HP is not your issue!!!

When you turn the pump off, does the water in the pump basket stay full or does it drain back into the pool?

If it drains back into the pool, then you have an air leak. It is just like putting your thumb over the end of a straw and pulling it out of a glass of water. The water in the straw will stay there until you take your thumb off of the end of the straw.

You may have more than one problem. I say that because of your comment that your pump will not prime without the spa drain on. As a test, I'd put the Intake and Return valve in the spa mode, with the pump off, and then turn the pump on and see if it primes ok. I'd also shut off the pump, while in the Spa mode, and see if the pump drains down.

Then report back your results.

When was the last time you opened and cleaned your filter?

Thanks,

Jim R.

jim,

ill try that today and see what happens. Thanks!

 

[earevalo23rd]

E,

HP is not your issue!!!

When you turn the pump off, does the water in the pump basket stay full or does it drain back into the pool?

If it drains back into the pool, then you have an air leak. It is just like putting your thumb over the end of a straw and pulling it out of a glass of water. The water in the straw will stay there until you take your thumb off of the end of the straw.

You may have more than one problem. I say that because of your comment that your pump will not prime without the spa drain on. As a test, I'd put the Intake and Return valve in the spa mode, with the pump off, and then turn the pump on and see if it primes ok. I'd also shut off the pump, while in the Spa mode, and see if the pump drains down.

Then report back your results.

When was the last time you opened and cleaned your filter?

Thanks,

Jim R.

i'm back, after putting pool in backwash mode to prime pump. (only way i can prime pump)
1. I let it run for a few minutes, than shut off pump. Water did not drain from pump.
2. i put pool into spa mode tried priming pump that way, it did not prime. within a few minutes it lost prime,.
i shut pump off again, and checked for water draining from pump which it didn't.
3. I recently cleaned filter about a 2-3 weeks ago, when all these issues started happening.

One thing i just noticed is the filter pressure is kinda high, it's running at about 20-25psi, when it normally
runs at about 10-15psi, any ideas of this could be related to my issues? TIA

 

[Jimrahbe]

E,

If your pump only primes when you have the valve in the backwash position and won't prime when in the filter position, something is wrong with your filter.

I suggest that you open the filter and see what is going on.

Now would be a good time to make sure the backwash valve is working like it should and not broken inside.

Thanks,

Jim R.

 

[Poolbreh]

The filter is a fns correct? You opened up filter and cleaned it and recharged it with DE? What happens when you put the return valve 50/50 spa/pool.

 

[earevalo23rd]

E,

If your pump only primes when you have the valve in the backwash position and won't prime when in the filter position, something is wrong with your filter.

I suggest that you open the filter and see what is going on.

Now would be a good time to make sure the backwash valve is working like it should and not broken inside.

Thanks,

Jim R.

What kind of problems in filter would cause priming issues? what should i be on the look out for? i recently replaced one of the o-rings in the backwash valve which was leaking, it stopped leaking after i replaced it and figured that was the end of it. Thanks!

 

[Jimrahbe]

What kind of problems in filter would cause priming issues? what should i be on the look out for?

E,

I am not sure, but logically if the pump primes when the system is in the backwash position and does not prime when in the filter position, it would point to filter including the backwash valve. In fact, now that I think about it, it sounds more like a problem with the backwash valve itself.

For the pump to prime, water has to actually leave the pump and go somewhere. If it can't easily get through the filter/backwash valve it keeps new water from coming into the pump.

I have never worked on a push/pull valve, so have no idea what could be wrong, but it sure seems to point in that direction. Do you think it is possible for the backwash valve to be somehow assembled wrong?

Sorry to be of no help. Please keep us in the loop and let us know what you find.

Thanks,

Jim R.

 

[earevalo23rd]

E,

I am not sure, but logically if the pump primes when the system is in the backwash position and does not prime when in the filter position, it would point to filter including the backwash valve. In fact, now that I think about it, it sounds more like a problem with the backwash valve itself.

For the pump to prime, water has to actually leave the pump and go somewhere. If it can't easily get through the filter/backwash valve it keeps new water from coming into the pump.

I have never worked on a push/pull valve, so have no idea what could be wrong, but it sure seems to point in that direction. Do you think it is possible for the backwash valve to be somehow assembled wrong?

Sorry to be of no help. Please keep us in the loop and let us know what you find.

Thanks,

Jim R.

On the contrary, you've pointed me in a new direction! it kind of makes sense since all this kinda of started around the time i pulled the backwash valve to replace o-ring. i'm going to disassemble it tonight and inspect it.
Pool company is coming out for 3rd visit tomorrow and if they can't detect any leaks, gonna have them look at filter as well. Thanks and will keep you posted!

 

[MITBeta]

What does your water chemistry look like? DE filters are really good at masking algae problems, and now that you mention the high pressure at the filter, maybe you have a chronic, low grade algae problem that's clogging your filter and preventing your pump from moving enough water to stay primed.

Post a full set of results, please.

 

[earevalo23rd]

On the contrary, you've pointed me in a new direction! it kind of makes sense since all this kinda of started around the time i pulled the backwash valve to replace o-ring. i'm going to disassemble it tonight and inspect it.
Pool company is coming out for 3rd visit tomorrow and if they can't detect any leaks, gonna have them look at filter as well. Thanks and will keep you posted!

welp...it was not the backwash valve... I replaced the whole assembly and nothing. Pump does still not prime. Gonna let the experts do their work, they should be at my house this afternoon. Hoping for good news. Thanks for your help though...i appreciate it.

 

[earevalo23rd]

What does your water chemistry look like? DE filters are really good at masking algae problems, and now that you mention the high pressure at the filter, maybe you have a chronic, low grade algae problem that's clogging your filter and preventing your pump from moving enough water to stay primed.

Post a full set of results, please.

I checked chemistry a week ago and everything was good...Water is pretty clear considering pump isn't working at 100%.

 

[duckcmmndr]

welp...it was not the backwash valve... I replaced the whole assembly and nothing. Pump does still not prime. Gonna let the experts do their work, they should be at my house this afternoon. Hoping for good news. Thanks for your help though...i appreciate it.

Is your filter pressure still high? What you posted was almost a 50% increase over what you said was normal. I think these guys have you pointed in the right direction...I would guess filter as a culprit too.