Moving from 2-Speed to Variable Speed Motor?

We just got back from a vacation and found our 22-year old Pentair CCP 520 had a crack in the lower housing that was leaking a small dribble. I found a craigslist seller that was filling in his pool (new homeowner who not want a pool) and selling the 4-year old equipment at a great price. We bought his CCP 520 for $150, his Pentair 3HP VS pump for $150, and he threw in for free a Sta-Rite, 2HP, single-speed water feature pump. I have already replaced our old CCP 520 with his unit to solve the leak problem. Now I am considering installing the VS motor in place of the 2-speed set-up that we have used for 22 years. We are on our third 2-speed motor with each of the prior motors lasting 9 years and the current motor (AO Smith B985) having been installed in Nov 2018.

Our current wiring/timer set-up uses an Intermatic T104 and T106 wired in series as discussed in this how-to instructional from Inyo Pools. These timers are the same ones that were installed 22 years ago when we built the pool. We have four wires going to our current motor, as outlined by Inyo. The VS motor has three wires (2 black and 1 green), which I assume are two black hots and a green ground.

My questions:

Should I just keep my 2-speed set-up that has been working well for years?

We run 24/7 in the Arizona desert using low speed for 22 hours and high speed for 2 hours. We have a solar energy pricing plan that allows us a very low rate per kW of 6 cents during off peak and on peak hours. I was not sure we would be saving enough extra energy with the VS to spend the time switching out the 2-speed motor and messing around with the existing wiring and timers. We have a pop-up head cleaning system and I am not sure we could run the RPMs much lower than the 1725 RPM low-speed of the 2-speed motor and still have the heads pop up enough for decent circulation on low.

If the consensus is the switch from 2-speed to VS is worth the effort, does anybody have any advice for how I should rework the wiring to facilitate the switch?


Gold Supporter
Oct 4, 2020
Fort Worth, Texas
Pool Size
Salt Water Generator
SWG Type
CircuPool RJ-60 Plus
I’d just resell the single speed and the 3HP Intelliflo - you could likely get 3-4x what you paid fairly easily.

And as soon as you sell it, you’re old 2 speed will bite the dust.
  • Haha
Reactions: guinness


Well-known member
May 3, 2019
Pool Size
Liquid Chlorine
If the consensus is the switch from 2-speed to VS is worth the effort, does anybody have any advice for how I should rework the wiring to facilitate the switch?

Assuming you have the Intelliflo VS pump, you connect it directly to the breaker not a timer since it already has built-in scheduling.
I was looking at the wiring a bit yesterday. Looks like I can disconnect all wires coming from the house main breaker box to into the timer box then join the two disconnected, hot blacks to the blacks running out of the timer box to the motor. Then I would do the same for the ground wire. This would give me a direct wire path from the breaker box to the motor for two hot blacks and the ground. The existing white wire running from the timer box to the motor would be taped off and not used for the VS motor.
Thread Status
Hello , This is an inactive thread. Any new postings here are unlikely to be seen or responded to by other members. You will get much more visibility by Starting A New Thread