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McDonnell & Miller 311200 - 21-30 Replacement Float

McDonnell & Miller 311200 - 21-30 Replacement Float

Brand: McDonnell & Miller SKU: 311200
Regular price $692.77 USD
Regular price Sale price $692.77 USD
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OEM manufacturer warranty Genuine factory-sourced

Ships factory-new in original packaging.

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Maintaining precise water level regulation is essential for boiler safety, and the 311200 replacement float is engineered to restore optimal performance to your McDonnell & Miller 21 series controls. This component acts as the primary sensing element, ensuring that your system maintains the correct water line to prevent dry-firing and maintain thermal efficiency.

The float mechanism operates on a buoyancy principle, rising and falling with the water level inside the control chamber. As the water level fluctuates, the float triggers the switch assembly to either initiate makeup water or activate a low-water cutoff, providing critical protection for your hydronic or steam boiler system.

Key System Performance Baselines:

  • Precision Buoyancy: Calibrated to provide consistent, reliable activation of the switch assembly.
  • Corrosion Resistance: Manufactured from durable materials designed to withstand harsh boiler water environments.
  • OEM Compatibility: Precision-engineered for exact fitment within the model 21 series control housing.

āš ļø Application Profile: Used exclusively for the maintenance and repair of McDonnell & Miller Model 21 series boiler water feeders and low-water cutoffs. Ideal for commercial and industrial steam heating systems.

Performance ParameterEngineering Baseline Value
Manufacturer Part Number (MPN)311200
Model Designation21-30
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