Grundfos 00506176 Cartridge Assembly

The Grundfos 00506176 Cartridge Assembly represents a professional-tier service solution for UP25-64SF and UPS25-64SF series circulator pumps. As a veteran technician knows, replacing the internal cartridge is a cost-effective alternative to a full pump house replacement, restoring original hydraulic performance and head pressure. This rotating assembly features a stainless steel construction designed to withstand aggressive fluid chemistries and high-temperature cycling common in open-loop radiant heating and domestic hot water recirculation systems. The 00506176 cartridge ensures the wet-rotor design maintains optimal lubrication and cooling, preventing shaft-seize and audible vibration. Designed for precise mechanical fitment, this replacement pump cartridge eliminates the need for bypass piping modifications during maintenance. When diagnosing a dead-header or decreased flow rates, verifying the rotational integrity of the ceramic shaft and carbon bearings within this assembly is the standard protocol for restoring Grundfos circulator pump efficiency.

• Direct OEM Fitment: Engineered specifically for the Grundfos UP25-64SF, ensuring drop-in compatibility without field modifications.
• Commercial Grade Durability: The stainless steel rotor cladding and housing resist mineral buildup and corrosion in high-oxygen environments.
• Labor Efficiency: Allows for rapid field service, reducing system downtime and eliminating the cost of full-body plumbing re-work.
• Acoustic Performance: Precision-balanced components eliminate the resonance and cavitation noise often found in worn aftermarket rotors.

Is this cartridge compatible with cast iron Grundfos models?
This assembly is primarily engineered for the stainless steel (SF) versions. Check the nameplate for the 'S' designation to ensure the metallurgy matches your system requirements.

Do I need specialized tools for this installation?
Standard hex keys are sufficient to remove the motor head. Ensure the O-ring seat is cleaned and lubricated before seating the new 00506176 assembly to prevent housing leaks under pressure.

Can this restore a pump that has been dry-fired?
Yes, as long as the motor windings are intact, replacing the cartridge resolves most mechanical failures caused by dry-running or bearing seizure.

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.