Parker 398PD-4-4 Compression Double End Shutoff Pipe Fitting

Product Description

The PARKER 398PD-4-4 is a brass compression tube double end shutoff pipe fitting designed for fluid and gas line connections in HVAC, plumbing, and industrial service applications. It features a tube-to-pipe end connection configuration with a 1/4-18 NPTF thread standard, ensuring a pressure-tight seal on tapered pipe threads. Rated to a maximum working pressure of 150 psi and a temperature range of 0 to 150 degrees F, this fitting is suited for moderate-pressure service lines. Licensed tradespeople select this fitting when transitioning from compression tube runs to threaded pipe connections in tight or controlled-access installations.

The 398PD-4-4 is used in residential and light commercial HVAC systems, refrigeration line sets, plumbing supply runs, and similar fluid-handling assemblies where a shutoff function at both ends is required. Its double end shutoff design allows the line to be isolated at the fitting itself, reducing system downtime during maintenance or component swap-outs. The brass construction makes it appropriate for water, air, and compatible refrigerant or gas service within its rated limits.

Key Features

• Double end shutoff design isolates flow at the fitting for easier servicing
• Brass construction provides corrosion resistance for water, air, and compatible fluid service
• 1/4-18 NPTF thread ensures a pressure-tight tapered thread connection
• Tube-to-pipe end configuration transitions compression tube lines to threaded pipe
• Rated to 150 psi maximum working pressure
• Operating temperature range of 0 to 150 degrees F

Compatibility

Designed as an OEM-style replacement or new-installation fitting for compression tube-to-pipe connections requiring a double end shutoff in HVAC, plumbing, and light industrial fluid service assemblies.

Installation Notes

Installation should be performed by a licensed HVAC technician or plumber following applicable IFGC, IPC, or local mechanical codes. De-pressurize and isolate the system completely before removing or installing any compression fitting. Use appropriate tube cutters and deburring tools to ensure a clean, square tube end for reliable compression seal engagement. Do not overtighten the compression nut, as brass fittings can deform under excessive torque.