Rugged Construction: High-grade cast iron provides superior resistance to steam-side corrosion and thermal stress

The McDonnell & Miller 344100 (Model SA66-35) is a high-precision upper tube assembly engineered for the maintenance and repair of Series 67 low water cut-offs

and potential fire hazards

6 Cv equal percentage flow characteristic

Diagnostic Ready: Integrated 1/8" NPT pressure taps on both the left and right sides allow for rapid manifold pressure verification

Nordyne 624689R Interface Module Freon Rugged Construction: High-grade cast ironThe Nordyne 624689R Interface Module is a critical replacement component engineered for precise communication between the thermostat and the integrated furnace control board in specific Miller and Intertherm gas furnaces. This OEM interface board is designed to manage the ignition sequence and blower timing, ensuring the heating system operates within factory specifications. As a direct fit Nordyne replacement part, it addresses common diagnostic