Armstrong S-55-1 Series Cast Iron Centrifugal Pump 1/2HP

Circulate residential and light commercial heating water with Armstrong 106284MF-132 S-55-1, a 1/2 HP single-phase Series S pump for hydronic systems. Its cast-iron body, resilient-mounted motor, non-ferrous impeller, and copper-sleeved shaft suit boiler and heating-loop service where a three-piece pump can be serviced without replacing the entire piping run. The supplied listing identifies oil lubrication, so confirm the bearing arrangement before installation.

The motor operates on single-phase service, while the S-55-1 assembly uses a BUNA-N mechanical seal and the listed 225°F maximum temperature. The supplied data does not state voltage, flow, head, pressure, amp draw, dimensions, weight, or flange size. Because the MF designation may indicate a different bearing configuration than the oil-lubricated description, verify the nameplate and current Armstrong documentation before startup.

Key Features & Benefits

- 1/2 HP Motor: Supports residential and light commercial hydronic heating circulation.
- Single-Phase Configuration: Fits compatible building service for straightforward replacement planning.
- Cast-Iron Body: Provides the specified casing material for closed-loop heating systems.
- Non-Ferrous Impeller: Supports the listed rotating arrangement for compatible hydronic service.
- Alloy-Steel Shaft: Uses a copper sleeve within the supplied shaft configuration.
- BUNA-N Mechanical Seal: Helps contain circulating fluid around the shaft.
- Three-Piece Circulator: Provides a serviceable layout for compatible heating-loop installations.
- 225°F Maximum Temperature: Establishes the listed operating limit for compatible systems.

Why Choose Armstrong 106284MF-132 S-55-1

The S-55-1 gives contractors a 1/2 HP cast-iron circulator for residential and light commercial heating, but the bearing and lubrication description should be confirmed before service planning.

- Build: Cast iron, non-ferrous impeller, copper-sleeved shaft, and BUNA-N seal define the supplied assembly.
- Value: The three-piece layout can support component service without disturbing the connected piping.
- Audience: Suited to residential HVAC contractors, boiler technicians, property maintenance teams, and hydronic installers.

Applications & Use Cases

Use Armstrong 106284MF-132 S-55-1 for residential heating, light commercial hydronic loops, boiler branches, and compatible Series S piping. The supplied data does not provide overall dimensions, unit weight, port reach, or flange details, so verify bearing access, valve clearance, pipe support, motor orientation, and service space before installation.

Warranty & Support

- Warranty Terms Require Confirmation: Verify duration, coverage, registration, exclusions, and authorized service requirements with Armstrong or the seller.
- Confirm SKU 106284MF-132, S-55-1 model, motor voltage, bearing type, lubrication, impeller, and seal before ordering.

Fill and purge the loop, inspect the shaft seal, confirm the bearing service requirements, and verify the motor nameplate before startup. Monitor noise, vibration, temperature, and leakage during commissioning. Purchase the Armstrong 106284MF-132 S-55-1 cast-iron hydronic circulating pump through Mulmotor.com for authentic equipment, applicable warranty support, and model-verification assistance.