Pentair - UltraFlow Plus pump base for 2.2 kW motor - R390058MA

Pentair UltraFlow Plus pump base for 2.2 kW motor

This is the OEM pump base (pied de pompe) for the Pentair UltraFlow Plus at the 2.2 kW power rating. It forms the structural foot of the pump assembly, anchoring the hydraulic body to its mounting surface and keeping the unit level and stable during operation. Without a sound base, the pump body flexes under pipe load, accelerating seal and bearing wear.

What this pump base does in the UltraFlow Plus

The base sits beneath the volute housing and distributes the pump’s weight and pipe-stress forces evenly onto the installation surface. It carries the fixing points that bolt the complete pump to its pad or plant-room shelf, isolating vibration and preventing the unit from shifting under flow-induced thrust. A cracked or distorted base transfers that stress directly to the pump body and plumbing connections, producing leaks and noise.

Which UltraFlow Plus models it fits

This base is confirmed compatible with the Pentair UltraFlow and UltraFlow Plus family at the 2.2 kW rating — specifically the single-phase P-UFL-301 (230 V) and three-phase P-UFL-303 (400 V) variants. Verify your model code on the motor nameplate before ordering; bases are rating-specific and do not interchange across power classes.

Signs it needs replacing

Inspect the base if you see the pump rocking on its pad, hear a new low-frequency vibration at startup, or find hairline cracks radiating from any of the mounting-bolt holes. UV degradation and chemical exposure in poorly ventilated plant rooms cause the thermoplastic to embrittle over time, so a base that looks intact may still flex enough to misalign the volute under load.

How to install it

Isolate power and close the suction and return valves before you begin. Undo the stainless-steel clamp band that connects the motor block to the volute, lift the motor block clear, then remove the four mounting bolts securing the old base. Drop the new base into position, re-torque the mounting bolts evenly in a cross pattern, refit the motor block, and close the clamp band. Confirm the pump sits flat on the pad before reopening the valves and restoring power — the whole job takes roughly 20 minutes.