Grundfos 59896341 Pump

The Grundfos 59896341 (Model UPS15-58FC) is a heavy-duty, 3-speed hydronic circulator pump designed for versatility in residential heating systems. Featuring a cast iron pump housing and a high-efficiency 1/25 HP motor, this "Super Brute" model operates on 115V power and is engineered for closed-loop radiant heating, baseboard, and fan coil applications. The three-speed motor allows technicians to adjust the flow rate to match specific system requirements, delivering a max head of 19.5 feet and a max flow of 17 GPM. The wet rotor design ensures whisper-quiet operation by using the pumped liquid to lubricate the internal ceramic bearings, eliminating the need for manual maintenance. An integral check valve (IFC) is included to prevent thermo-siphoning and backflow, though it is removable for systems where an external valve is already present. Built with stainless steel rotor cladding and a composite impeller, this unit is a reliable replacement for multiple competitor models in zoning and hydronic HVAC setups.

Key Benefits

• 3-Speed Versatility: Replace over 30 different competitor models by selecting the optimal performance curve (Low, Medium, or High) for the zone.
• Integrated Flow Control: The removable check valve prevents heat migration and thermo-siphoning without the need for additional inline components.
• Silent Operation: The canned-rotor design ensures the motor remains virtually silent, making it ideal for sound-sensitive indoor installations.
• Internal Protection: Features impedance protection and an internal cooling system to prevent overheating and extend the life of the cast iron assembly.
• Flexible Installation: Standard 2-bolt flange connection (USA Oval) compatible with 3/4", 1", 1-1/4", and 1-1/2" piping via standard flanges.

Common Questions

Can I use the UPS15-58FC for potable water systems?
No. This unit features a cast iron housing intended only for closed-loop hydronic heating and cooling. For domestic hot water (potable) applications, a stainless steel or bronze housing model is required to prevent corrosion.

What is the purpose of the 3-speed switch?
The switch adjusts the pump head and flow velocity. Setting the pump to the lowest speed that still satisfies the zone’s heating requirement reduces electrical consumption and prevents "velocity noise" in the pipes.

Do I need to bleed air from this pump?
While the pump is self-lubricating, the system must be purged of air during commissioning. The large silver screw on the face of the motor can be carefully loosened to vent trapped air from the rotor chamber manually if needed.

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Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.