O-ring 2" flat O-ring Gasket

The 2" Flat O-ring Gasket is a flat-profile rubber gasket used at heater unions on Arctic Spas — the connections at each end of the spa's heater tube where the heater meets the plumbing. Unlike a round-profile O-ring that seats in a groove, this is a flat washer that compresses between two flat union faces to make a seal.

Why heater gaskets are special: Heater unions live in the hottest, most thermally cycled spot in the entire spa plumbing run. The gasket expands and contracts every time the heater turns on and off, and after enough cycles it loses its springiness, develops a flat-spotted profile, and eventually starts weeping water at the joint. Catching the leak early matters — a slow drip onto live electrical components inside the equipment bay is a real failure risk for the heater controller.

When to replace: Replace the gasket any time you notice water around the heater, when you're disconnecting the heater for service, or any time the existing gasket has visible compression damage or hardening.

How to install: Drain the spa below the heater first. Disconnect the union, remove the old gasket, clean both mating faces with a paper towel, and seat the new gasket flat. Hand-tighten the union — never use a wrench on a plastic spa union.

Quick tips:

• Replace both heater gaskets at the same time — they age at the same rate and you don't want to be back here in three months
• If your fittings are 2.5" rather than 2", you need the 2.5" Flat O-ring Gasket instead
• Bring the old gasket to one of our three Ontario showrooms if you're not sure which fits your heater