Pentair - UltraFlow Plus pump base 0.55–1.50 kW - R39005800

Pentair UltraFlow Plus pump base 0.55–1.50 kW

This is the structural base that sits beneath the pump body on single-phase UltraFlow Plus units rated between 0.55 kW and 1.50 kW. It mounts to the plant-room floor or pad, absorbs operational vibration, and holds the entire pump assembly square and stable during continuous filtration cycles. Without a sound base, the pump body shifts under load, accelerating wear on the volute, motor feet, and pipework connections.

What this pump base does in the UltraFlow Plus

The base is the primary anchor between the pump and its installation surface. It distributes the weight and torque of the motor and wet end evenly, preventing micro-movement that would otherwise loosen the bolts securing the strainer pot and volute over time. It also spaces the pump correctly off the floor to allow airflow around the motor casing and provide clearance for the drain plug.

Which UltraFlow Plus models it fits

R39005800 is confirmed to fit single-phase UltraFlow Plus pumps from 0.55 kW up to 1.50 kW, and is also listed as compatible with the IntelliFlo UltraFlow VSD and UltraFlow VS variable-speed variants that share the same wet-end and motor-frame dimensions. The separate reference R390058MA2 covers the 2.20 kW tri-phase version — confirm your motor rating and phase configuration before ordering. Fit your model number against the Pentair UltraFlow Plus European exploded diagram (position 19) to verify.

Signs it needs replacing

A cracked or broken base lets the pump rock on its mounting surface, producing a rhythmic vibration or knocking that travels through the pipework. You may also notice that the pump feet bolts work themselves loose repeatedly, or that the base has split along the mounting lug — a common failure after freeze-thaw cycles or overtightened fixing bolts. Continued operation with a damaged base stresses the motor shaft seal and shortens its service life.

How to install it

Isolate the pump from mains power and close the inlet and outlet valves before you begin. Remove the existing bolts and washers securing the pump body to the old base — retain the hardware if it is undamaged, or replace with genuine R98219800 bolts and washers. Lower the pump onto the new base, align the feet, and torque the fixings evenly so the pump sits flat before reconnecting pipework and restoring power. The job takes around 20–30 minutes with a socket set.