Replacing Single Speed Motor with 2-Speed Motor

  • Last Post 20 March 2017
  • Topic Is Solved
JohnSellars posted this 19 March 2017

I recently added a heater to our pool/spa and was told my current pump would be fine to heat only the spa (which is all I plan on using in the winter anyway). When I shut the valves to/from the pool off and leave the valves to/from the spa open, the pump filter fills with air and eventually breaks the prime on the pump. I believe switching to a 2-speed or variable pump would solve my problem as I am effectively trying to use the same pump to filter a ~20,000 gallon pool/spa during the day and a ~550 gallon heated spa on occasion. Is that a reasonable assumption?

I currently have a Pentair Challenger high performance pump (CHII-N1-2A) mated to a Century B855 2.0HP/SF1.10 single speed pump.

Would the B2983 1.5HP/SF1.47 motor and "Toggle Switch and Canopy Kit for 56Y 2-Speed 2512558-001" be a suitable replacement set?

Order By: Standard | Newest | Votes
JohnSellars posted this 19 March 2017

Also, would the ECM27SQU Variable Speed motor be a suitable replacement motor?

InyoRob posted this 20 March 2017

Hello JohnSellars - It sounds like the pump is cavitating when you switch to spa mode. The pump is trying to pull more water than it can receive through the spa only line. Switching to a 2-speed B2983 or variable speed ECM27SQU would allow you to lower the RPMS and allow the pump to operate smoothly.

  • Liked by
  • JohnSellars