Split Nut Union for Heater 2”

The 2" Split Nut Union for Heater is the threaded split-nut union fitting used at the heater connections on Arctic Spas. The split-nut design lets you tighten the union without needing to spin the heater itself — critical when the heater is sandwiched between fixed plumbing on both sides and can't rotate.

When you'll need to replace it: Replace the split nut union when the existing nut is cracked, the threads have stripped, or the seal flange has gone brittle from years of thermal cycling. Heater unions are the most-stressed plumbing joints in the spa — they expand and contract with every heating cycle, so the unions wear faster than other plumbing connections.

How to install: Drain the spa below the heater first. Disconnect the existing union, replace any worn O-rings or flat gaskets at the same time (see the 2" Flat O-ring Gasket for heater unions), seat the new split-nut union, and hand-tighten. Never use a wrench on a plastic spa union — cracked unions are how customers find out the hard way.

Quick tips:

• Replace the matching gasket at the same time — they age together
• Bring the old union to one of our three Ontario showrooms for matching if you're not sure of the fit