Heater 5.5kW | Flo-Through

The 5.5kW Flo-Through Heater is a straight-tube replacement heater for Arctic Spas. It's the standard 5.5 kilowatt heater that fits most current and recent-vintage Arctic Spas with the in-line straight heater configuration. Comes with the integrated power cord pigtail ready to land on the motherboard.

When you'll need a new heater: Spa heaters typically last 5-10 years of normal use. The most common failure modes are the heater element scaling over and burning out (preventable with regular use of Natural Chemistry Scale Free), the high-limit sensor tripping repeatedly because of internal corrosion, or visible water leaks at the heater body. The classic symptom is a spa that runs the pumps fine but won't hold temperature — the controller can't get the heater to fire.

Will this fit my spa? Yes, on most current and recent-vintage Arctic Spas with the standard straight-tube in-line heater layout. If your equipment bay layout requires the heater to make a 90° turn, you need the 5.5kW 90-Degree Heater instead. Bring a photo of your old heater and the equipment bay to one of our three Ontario showrooms if you're not sure which configuration fits.

Important: Heater installation is not a casual DIY job — you're working with 240V, GFCI-protected wiring, and the high-limit sensor calibration matters for your safety. Most spa owners book a service tech to install a replacement heater. If you're an experienced electrical DIYer and want to do it yourself, drain the spa below the heater first, follow the spa's wiring diagram precisely, and confirm the GFCI holds before declaring the job done.

Quick tips:

• Replace the heater union gaskets at the same time — see 2" Flat O-ring Gasket for heater unions
• If you've been on hard water without a sequestrant, expect the new heater to also scale up unless you start a Scale Free routine now