1HP Pump vs. 1.5HP Pump for AGP

Apr 16, 2011
8
PA
Hello:

I've searched for a good answer for this question but can't seem to locate a good comparison in the forums. I have a 24' round Above Ground Pool (52") which holds about 13,000 gallons. Last year I replaced the sand filter which was leaking and bought a Hayward S180T but I really think the cheapo 1HP replacement pump I purchased from my local dealer is not doing the job.

Basically there is just a lot of dirt that accumulates on the bottom of the pool and it's my educated guess based on the power of the water being pulled into the skimmer and the output into the pool that the pump is not doing a great job at all (probably why it was so darn cheap at the time.) I never had dirt problems before I replaced the pump so I'm thinking that is the culprit. Not to mention, the suction when I try to vacuum is extremely poor so all signs point to needing a new/better/more powerful pump.

Everything I'm reading puts my 24' AGP in the category where it breaks off from a 1HP to a 1.5HP. Is a 1.5HP too much or just right? Did I just get a bad 1HP pump and should I be buying a better brand/product that will do the job at 1HP?

I'm on the fence about getting a 1.5HP. I've been leaning towards the Hayward SP1580X15 Power-Flo LX but wanted to see what you all think before I bite the bullet. Obviously I just don't want to make another mistake.

Would appreciate your feedback. Thanks!
 
You shouldn't really need a large pump. I have a 20k pool and a 1/2 HP pump. Even the smallest pumps, except maybe an Intex pump, should be enough. But even the largest pump won't keep debris off the floor either, that is what a vacuum is for.

However, if you are vacuuming up debris and then find it on the floor again the next day, that could be a problem with the filter. Did you recently have an algae bloom and had to SLAM the pool? If so, sand filters don't do such a good job with dead algae. Adding a little DE to the filter could help.

Is the filter pressure the more with the new filter than the old filter?

Also, I forgot to add that on typical AG plumbing, a 1 HP pump's flow rate will only be a few GPM lower than a 1 1/2 HP pump. So not much different.
 
You shouldn't really need a large pump. I have a 20k pool and a 1/2 HP pump. Even the smallest pumps, except maybe an Intex pump, should be enough. But even the largest pump won't keep debris off the floor either, that is what a vacuum is for.

However, if you are vacuuming up debris and then find it on the floor again the next day, that could be a problem with the filter. Did you recently have an algae bloom and had to SLAM the pool? If so, sand filters don't do such a good job with dead algae. Adding a little DE to the filter could help.

Is the filter pressure the more with the new filter than the old filter?

Also, I forgot to add that on typical AG plumbing, a 1 HP pump's flow rate will only be a few GPM lower than a 1 1/2 HP pump. So not much different.

A huge issue is the vacuuming part. The amount of time it takes to vacuum the pool is crazy as the suction is simply not good at all. I know with the original 1HP Waterway pump that came with the pool years ago that we replaced, the suction was MUCH better than what I have now with this pump. That has to be a pump issue, no? No issues with Algae bloom so I know that's not the problem.

Regarding the pressure on the S180T filter, average range on it has been 7-8 PSI and I know the original Waterway pump was closer to 12 PSI if I remember correctly. It's the combo of the suction, the dirt, the pressure and just my looking at the return in the skimmer and the feel of the pressure at the return that makes me think the pump is the issue. But again, 1HP may be right.....I just may have a lemon on my hands. I'm just afraid to buy another 1HP and find the same issues which is why I'm heehawing over the 1.5HP.
 
The powerflow lx 1hp is a good pump for my pool and works just fine with a manual vac and auto vac. If I ever replace it, I won't be looking for more power, just a two speed to save energy skimming longer. If you were to get the same pump and not be satisfied, your plumbing or sand filter is too small or is a long run. I personally think a 1.5hp is too much for a 18" sand filter.
 
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Regarding the pressure on the S180T filter, average range on it has been 7-8 PSI and I know the original Waterway pump was closer to 12 PSI if I remember correctly. It's the combo of the suction, the dirt, the pressure and just my looking at the return in the skimmer and the feel of the pressure at the return that makes me think the pump is the issue. But again, 1HP may be right.....I just may have a lemon on my hands. I'm just afraid to buy another 1HP and find the same issues which is why I'm heehawing over the 1.5HP.
So what is the new "cheepo" pump from your dealer? Make/model#?
 
I have 1.5HP Hayward on their s180.
I bought it because that was there before. But when I spoke to pros about it (pistfactum) they all told me 1.5HP is too much for it, and ideally it is 0.75 to 1HP. Not that I am having problems, but....
 
The cheepo pump I'm using now is a "Maxi-Pump" model 72728. The pool store had like 30 of them all in plain white boxes when I bought it last year. It's almost like they went to Alibaba.com and bought a ton of them from China to resell. Not that that's bad but the low price and quantity they had would lead me to believe that.

I actually reached out to Hayward and their tech emailed and told me the 1.5HP Hayward pump would be perfectly matched for the S180T filter. I guess there's no right or wrong answer here.
 

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The cheepo pump I'm using now is a "Maxi-Pump" model 72728.

Did the pump come with a head curve? I can't find anything online.



I actually reached out to Hayward and their tech emailed and told me the 1.5HP Hayward pump would be perfectly matched for the S180T filter. I guess there's no right or wrong answer here.
As I mentioned before, the 1.5 HP PowerFlo LX has only 1 GPM more flow rate than the 1 HP PowerFlo LX so very little difference between the two pumps.

However, for an 18" filter, you don't want to exceed more than about 35 GPM. On typical pool plumbing, both PowerFlo will well exceed that so you have the potential for filter damage and poor filtering.
 
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