Grundfos gf-99163972 Stainless Steel Circulator Pump

Product Description

The GRUNDFOS gf-99163972 is a variable-speed, stainless steel circulator pump designed for residential and light commercial hydronic heating systems. Built around a permanent magnet motor, it delivers significant reductions in power consumption compared to standard single-speed circulators. The pump features an AUTOADAPT function that continuously analyzes system conditions and adjusts speed to match actual heating demand. With a flow range of 0 to 21 GPM, a maximum head of 18 feet, and operating temperature limits of 36 degrees F to 230 degrees F, it covers a wide range of zoning and distribution applications. It ships with a line cord for straightforward electrical connection. Licensed HVAC technicians and plumbers are the primary installers.

This pump is suited for zoning applications in hot-water heating systems where variable demand and energy efficiency are priorities. The flanged-by-flanged connection type integrates directly into standard hydronic piping configurations. Its stainless steel construction resists corrosion in closed-loop water systems. The included line cord allows connection to a standard 115-volt branch circuit without the need for hardwired control panels in many installations. It is rated for single-phase, 60 Hz power at 0.65 amps, making it compatible with typical residential electrical service.

Key Features

• AUTOADAPT variable-speed control continuously matches pump output to system heating demand
• Permanent magnet motor reduces power consumption relative to fixed-speed circulator designs
• Stainless steel construction for corrosion resistance in closed-loop hydronic systems
• Flow range of 0 to 21 GPM with a maximum head of 18 feet
• Rated for operating temperatures from 36 degrees F to 230 degrees F and pressures up to 150 psi
• Includes line cord for direct 115-volt plug-in installation

Compatibility

Designed as an OEM-style replacement or upgrade circulator for residential and light commercial hydronic zoning systems using flanged-by-flanged piping connections and 115-volt single-phase electrical supply.

Installation Notes

Installation should be performed by a licensed plumber or HVAC technician in accordance with applicable local mechanical codes. Shut off system pressure and drain the affected loop before removing or installing the pump. Verify that the existing circuit is rated for single-phase, 115-volt, 60 Hz service before connecting the line cord. Do not operate the pump dry; confirm the system is filled and purged of air before startup.