Need a new pump :(

[AnnaK]

Our pool pump quit running the day before we left on vacation. There was no time to take it apart to see if we could make it work again. I loaded the pool with chlorine (about 20 ppm), stirred it in with the leaf net, and put the solar cover on. Got home last night to perfectly clear water!

We're still unpacking the trailer and haven't yet had time to dismantle the pump. Just in case we do have to buy a new one I would very much appreciate your opinion on make and HP.

The current pump is a 1.5 HP 2-speed Pentair at the end of its seventh season. The AGP holds about 12,500 gallons and we have a 19" sand filter.

I definitely want to get a 2-speed pump again. I run it on low speed during the night for about 6 hours and on high when I vacuum and for backwashing. High speed has always produced excellent vacuum suction.

The 1.5 HP might be too much and I'm thinking of getting a 1 HP 2-speed. Pentair or Hayward? What are your thoughts?

[BigDave]

Remember to consider Service factor when comparing pump/motor horsepower ratings.

[AnnaK]

With "service factor" do you mean ease of repair?

[BigDave]

Nope, Service Factor is a rating applied to motors that is multiplied by rated HorsePower to determine Brake HorsePower. Brake HorsePower is the amount of power the motor will produce before stopping.

Many inground pool pump manufacturers manipulate Service Factor and offer what is essentially the same pump with the same performance with two different HP ratings; one full-rated and one up-rated (or max-rated). This practice can make comparison harder, not exactly apples to oranges but apples to cored apples. Above ground pump makers don't seem to publish Service Factor rating at all - making comparison that much harder.

It makes sense to me to put in a smaller pump especially if your clean filter pressure is pretty high.

[AnnaK]

Thanks for the education. My question shows how very little I know about pool pumps. I did learn a whole lot today though. Hayward has a nice PDF out there to help calculate pump size and AO Smith has a lot of good info as well.

The clean pressure of my filter is approximately 18 psi on high speed. Because the gauge we have on it goes to 60 psi I can't really say what clean pressure at low speed is, somewhere between 5 and 8 psi, I think. Next season I want to get a gauge that goes only to 30 psi so I can get better accuracy.

Anyway, we've decided to get a Pentair Dynamo 1HP Dual Speed - 11.0/2.9A 115V - model 340204.

The seller is PoolSupplyWorld.com. Have any of you ever dealt with them? If so, what has been your experience?