Amana-Goodman B1789859 Restrictor Orifice

The Amana-Goodman B1789859 Restrictor Orifice is a precision-engineered fixed-bore metering device designed for HVAC refrigerant flow control in specific evaporator coils and heat pump systems. Featuring a .059 orifice size, this component is critical for maintaining the correct pressure drop across the liquid line, ensuring optimal refrigerant expansion and evaporator saturation. As an OEM replacement part, the B1789859 ensures the system operates within manufacturer-specified subcooling and superheat parameters. This Goodman expansion orifice is machined to tight tolerances to prevent turbulent flow and hunting, which are common issues with aftermarket alternatives. For contractors performing AC system maintenance or coil replacements, verifying the piston size against the outdoor unit's charging chart is essential for preventing compressor slugging and ensuring long-term HVAC system performance. This component is compatible with a wide range of R-22 and R-410A Goodman, Amana, and Janitrol air handlers and uncased coils.

• Accurate Metering: The .059 bore size provides precise thermal expansion regulation for consistent cooling cycles.
• OEM Compatibility: Genuine Amana-Goodman replacement part ensures exact fitment within the distributor assembly.
• System Reliability: Helps maintain proper refrigerant velocity to ensure efficient oil return to the compressor.
• Standardized Installation: Simplifies field service during orifice piston replacement without requiring TXV conversion.

How do I verify if the .059 orifice is correct for my tonnage?
Always reference the charging matrix on the outdoor condenser's service panel; the required restrictor orifice size depends on the matched indoor coil and total system capacity.

Can this orifice be used with both R-22 and R-410A systems?
Yes, provided the refrigerant flow rate and pressure ratings of the specific system match the .059 physical diameter requirements found in the technical data sheet.

What are the signs of a clogged or incorrectly sized restrictor?
Improper sizing typically manifests as abnormal head pressures, evaporator icing, or insufficient cooling due to restricted refrigerant expansion.

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.