McDonnell & Miller 332800 Fittings

The McDonnell & Miller 332800, also identified by model number MA259, is a specialized Quick Hook-Up Fitting kit engineered for seamless integration with 42A, 47, 47-2, and 64A Series low water cut-offs and feeders. These precision-machined fittings allow contractors to bypass complex manifold piping by installing the control unit directly into the existing boiler gauge glass tappings. By utilizing the MA259 fitting, you maintain the critical centerline dimensions required for accurate water level sensing while re-mounting the gauge glass onto the fitting itself. This configuration ensures the McDonnell & Miller 47-2 or 64A Series remains in the path of the boiler's actual water level without obstructing the visual reference of the sight glass. Built for high-pressure durability and thermal stability, the MA259 Quick Hook-Up Fittings reduce labor time during boiler control replacement and provide a rigid, leak-resistant connection points for heavy-duty HVACR steam applications.

• Direct Integration: Mounts directly into 1/2 inch or 3/4 inch gauge glass tappings, eliminating the need for additional piping headers.
• System Compatibility: Specifically designed for McDonnell & Miller 47 Series water feeders and 64A Series low water cut-offs.
• Preserves Visual Inspection: Offset design allows the original sight glass to be reinstalled onto the fitting for continuous monitoring.
• Reduced Leak Points: Minimizes the number of threaded connections compared to field-fabricated "swing-joint" assemblies.
• Rugged Construction: Engineered to withstand the thermal expansion and contraction cycles of high-pressure steam boilers.

Which boiler controls are compatible with the MA259 fitting?
The MA259 (332800) is designed for the 42A, 47, 47-2, and 64A Series. It ensures the correct vertical alignment between the control's float chamber and the boiler water level.

Can I use these fittings to replace a standard NPT pipe connection?
Yes, these fittings are intended to simplify installation where traditional pipe threading is impractical, allowing direct attachment to the boiler jacket through the gauge glass ports.

Does the MA259 include the upper and lower fitting components?
Yes, this is a complete "Quick Hook-Up" kit containing both the upper and lower assemblies necessary to mount the control and the sight glass concurrently.

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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.