Sizing replacement pump

[TonyB]

I am replacing a 2014 Pentair Superflo 1hp. I didn't realize how loud the pump had gotten until my friend installed a pool and I heard (barely!) his new pump. My pump makes a wub, wub, wub sound. After reading several threads I'm leaning towards the bearings are needing to be replaced. This is the 2nd SuperFlo I have replaced in 10 years.
IG pool, 15k gallons, SD60 sand filter, Hayward Heater, Pentair IC20 SWCG. 3 returns (35' longest run). Skimmer approximately 40' from mechanicals. All plumbing to mechanicals is 1 1/2" PVC.
The mechanicals are located right by where we gather (bad planning on my part!) so noise is a HUGE concern. I was looking at the WhisperFlo line. My confusion is trying to determine the correct pump. My contractor installed the 1hp SuperFlo originally. The WhisperFlo 1hp, however, seems to be a LOT more powerful. Would the better choice be to drop down to the 3/4 hp or maybe even the 1/2 hp?

As always, any help is much appreciated.

Thanks!!

 

[foobert]

Firstly, I'm not sure that 3-year old bearings are the likely culprit for the sound you describe. Are there air bubbles in the strainer basket?

If noise is a concern, I'd suggest a 2-speed pump (or even a variable speed if you have a good reason for that level of flexibility). Running on low will be substantially quieter, save power, and give the flexibility to run at high speed for cleaning, etc.

Your 1.5" plumbing is also going to put you into the "high-head" category. As for proper sizing of pump, I'd suggest giving this a good read.

There are quite a number of factors to consider, but, as a quick example, a 1HP whisperflo using Head Curve A gets ~60GPM on high speed, yielding about a 4 hour turn-over time. On low speed, double that time as the flow is roughly half, but, it'll accomplish the same turnover using about 1/2 of the power (after factoring in the 2x longer run-time).

You can also replace only the motor for your pump with 2-speed motor. Its only 4 bolts to remove the motor form the pump body.

 

[kadavis]

Pentair - SuperFlo VS Variable Speed Pump, a lot of people seem to like this pump. Would be an easy install, may come with utility rebates, and can be adjusted to the flow you desire

 

[TonyB]

Thanks for the feedback. I am looking at going with a 2 speed Pentair motor. I have an Easytouch 8 panel that controls everything. As anybody who is familiar with Pentair's understands, their installation and wiring instructions are written in another language. Anybody have any suggestions for wiring up this new motor before I purchase. I found a thread that mentioned Pentair's "special" $99 relay, but didn't elaborate. I plan on running pump on low 99% of the time and kicking up to high for vacuuming or when needed for some other reason

Again, appreciate everyone's input.

 

[jblizzle]

My two speed pump just uses two of the high voltage relays in my Hayward system. I would imagine you can do the same. I'm not sure why you would need $100 add on. I have no idea how the programming in your system works though.

 

[kadavis]

https://www.poolsupplyunlimited.com/pentair-520198-automation-2-speed-pump-relay/20166p1, yes you do have to buy there two speed relay

 

[TonyB]

Ordered and installed 1hp two speed pump and Pentair relay. Started right up (both speeds) like a champ. I programmed a circuit in my ET8 to run pump on high when heat is own. No problems. The only problem I'm having is the red light on my SWCG is saying low flow and therefore not producing CL. Anyone have experience with this?