Pentair Compression Nut Only | Rainbow Automatic Feeder Model 300 Series | R18706Z

Description

The Pentair Compression Nut Only (R18706Z) is the OEM replacement compression fitting nut for the Rainbow Automatic Feeder Model 300 series, including Models 300, 302, 300-19, and 300-29.

What It Does

This compression nut secures tubing connections on the Rainbow Automatic Feeder, maintaining a leak-free seal at the feeder’s inlet and outlet tubing ports. A cracked, stripped, or missing compression nut allows chemical solution to bypass the fitting, resulting in uncontrolled dosing and potential equipment damage. Replacing this nut restores a positive, watertight connection at the tubing junction.

Specifications

Fits Into

Compatibility is based on Pentair parts documentation and available OEM records. This is not an exhaustive list. For certainty, verify the part number in your equipment’s manual or on the original part itself before ordering.

Pro Tip

Compression nuts on chemical feeders are exposed to concentrated sanitizer solutions and can become brittle or cross-threaded over time. When replacing this nut, inspect the corresponding compression ferrule and tubing end for cracking or chemical degradation — replacing the nut alone on damaged tubing will not produce a reliable seal. Hand-tighten first to confirm thread engagement, then snug with a wrench — overtightening will crack the nut.