Discussion and Consideration of Change Order #2 – Tricon Construction – Tiffin Water Treatment Facility Upgrade Project – Motion to Approve — K.4

The pump is built with cast bowls and cast impellers. They have imperfections which will a ect the e iciency. This is part of why there are numerous grades. The other thing is as one trims the impeller the e iciency decreases. I will have to take responsibility for part of this problem. In reviewing my paperwork and email correspondence, I see that I did not convey the Grade 2B 75% e2iciency requirement. Unless otherwise instructed, the factory tests for flow and head. However, this does not explain why the performance testing came in 4% lower in e2iciency in comparison to the factory certified curve in their submittal. I’m copying the Pentair personnel for their comments on this. From: Clint Wienen <[email protected]> Sent: Monday, February 2, 2026 12:05 PM To: Gary Ganoe <[email protected]> Subject: Tiffin WTP Low Lift Pumps Hi Gary, Just wondering if FBs has an explanation of why the e2iciency is approximately 4% lower for the performance tests compared to the SD for the low lift pumps? Also don’t they perform the hydraulic test with the actual motors that will be used? Test curves were with a 15-hp/1800 rpm motor. SDs indicated that 10-hp motors that are 1760 rpm will be provided. Thanks, Clint Wienen, PE | Senior Project Engineer MSA Professional Services, Inc. 100% Employee Owned +1 (563) 584-2897 7