Firstco Orifice Piston

The Firstco Orifice Piston is a refrigerant metering device (also called a piston metering device, fixed orifice or flow restrictor) for residential and light commercial HVAC systems, including heat pumps and air handlers. It sits in the liquid line at the indoor or outdoor coil. It controls how much liquid refrigerant flows into the evaporator, which helps the system cool and heat efficiently.

Key Features:

• Precision metering: A calibrated opening sets refrigerant flow for the system it is matched to.
• Fixed-orifice design: A simple piston style with no moving control parts to adjust.
• Direct replacement: A Firstco (First Company) replacement part for pistons used in First Co. equipment.
• Compact and easy to install: It is small and drops into the piston body or distributor fitting during a standard service.

Each variant in this line has a different orifice opening. Match the opening to your equipment's specifications so the system gets the correct refrigerant flow. Firstco has supplied HVAC components and replacement parts for many years.