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**CUPCCA Pre-Qualified Contractors Only** Bid #572 Variable Frequency Drive (VFD) Installation for Pool Pumps

Bid Documents

RFI #1 Question: Is there a preferred VFD manufacturer?

Answer: The District prefers Danfoss.

RFI #2 Question: How will the new VFD be controlled? By an external source, if so, what type?

Answer: The VFD will be controlled by programming, taking into consideration health code requirements, temperature, and existing chemical addition, filtration, heating, and other pool operating systems. There is no requirement to integrate VFD controls with a Building Management System.

RFI #3 Question: How will pool staff be able to change usage time for special events? Would it require special programming?

Answer: The VFD system must have programming and bypass capabilities.

RFI #4 Question: Who would be the District staff we would work with?

Answer: The Maintenance, Operations or Energy Management Departments.

RFI #5 Question: Are you requesting that we supply new electric motors for the two pool pumps 30 & 40 HP? It states the motors will be controlled through OUHSD system what type of system? There are pages stating we are supposed to check such as mechanical and control but it is for AC.

Answer: If existing motors are compatible with the VFD and existing equipment, there is no need to replace them. If they are not compatible, the motors would need to be replaced by the contractor. The VFD controls the motors through programming, taking into account flowrate, temperature, chemicals, filtration, heating systems, and health code requirements. There is no requirement to integrate VFD controls with a Building Management System. Please disregard references pertaining to HVAC.