Question About Filter Max Flow Rate (62 gal/min) and 1 HP Pump

[Feernot]

My Doughboy Hydrosphere pool came with a W. Cooper Ranger 25" Sand Filter (equivalent to Hayward S244T Pro-Series filter) with 300 lbs sand capacity, a suggested flow rate of 62 gal/min 3720 gal./hour, and 1 1/2" plumbing connections. It also came with a 1HP Blue Thunder pump with a sticker on it that says 93.5GPM QMax, whatever that is. It is a 12X24 oval pool with 6,800 gallons and only 1 skimmer and 1 return. Is my pump potentially too big and putting unnecessary pressure on my filter?

Blue Torrent AC PSP1056 1HP Blue Thunder 1 Speed Pool Pump
Model: AC PSP1056
Volts: 115/230V
Hz: 60
Amps: 11.5/5.8
Hmax: 18.5M
Qmax: 355L/min(93.5GPM)

 

[mas985]

The maximum flow rate is at run out without any head loss. The actual flow rate is dependent on the plumbing setup but for most AG pools, the plumbing is quite restrictive so it is unlikely that the flow rate is anywhere near the maximum and usually less than 30% below the maximum.

Also, if the pump and filter is sold together, they are usually matched fairly well.

 

[Feernot]

The actual flow rate is dependent on the plumbing setup but for most AG pools, the plumbing is quite restrictive so it is unlikely that the flow rate is anywhere near the maximum and usually less than 30% below the maximum.

What do you mean by the plumbing usually being restrictive? In my case, everything is hard plumbed at 1.5" from skimmer to pump to filter and back to the return.

 

[mas985]

First, it is important to understand that every pool plumbing system is restrictive (i.e. has head loss) and no pump should operate anywhere near run out.

But to qualify my statement, on typical AG pools, the plumbing is usually restrictive because:

A) AG pools typically use 1.5" plumbing is used which is more restrictive than larger plumbing that is used in IG pools (2"+).
B) AG pools typically have one return with a small eyeball which is very restrictive. IG pools usually 2+ and larger eyeballs.
C) AG pools typically have sand filters on the small side which again are very restrictive. IG pools usually have larger filters which in general are less restrictive.

So in general, AG pools will typically have a higher head loss plumbing curve than do IG pools. It isn't always the case but most of the time it is true.

What is the operational filter pressure?

Head loss from the filter to the pool = PSI * 2.31

 

[1poolman1]

If you are hard plumbed with 1.5" PVC throughout your system, the maximum flow rate for that pipe, for pool purposes, should be about 48gpm. That is not something you can set with a single-speed pump, but is probably what you would see with your setup. That's one reason VSP are so nice. If you have 1.5" fittings connected with the usual hoses that come with an above ground pool, the flow will be less because water can't flow as easily through corrugated hose as it can in smooth-bore pipe.