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Sta-Rite Max-E-Therm 400,000 BTU Heater -Natural Gas - SR400NA

in stock, ready to be shipped
Save 24% Save 24%
Original price $3,609.99
Original price $3,609.99 - Original price $3,609.99
Original price $3,609.99
Current price $2,726.10
$2,726.10 - $2,726.10
Current price $2,726.10

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Product Description

The Sta-Rite Max-E-Therm 400,000 BTU Heater -Natural Gas SR400NA is one of the most unique pool heater on the market. Made from a composite shell, the Max-E-Therm utilizes PMG combustion technology to produce the highest efficiency (85%) in its class, while keeping NOx emissions to a minimum. That means less time waiting for your pool or spa to warm up, and more time enjoying it.

Sure, a beautiful pool looks inviting, but its cold water can keep you high and dry. Which is why it pays to have a Sta-Rite Max-E-Therm High Performance Heater. After all, when the waters just right, you maximize the enjoyment of your pool experience. The fast-heating Max-E-Therm makes your pool irresistible on cool nights. It also allows you to extend your pool season.

Unlike other heaters, Max-E-Therm offers you the latest advances from Sta-Rite: a rustproof exterior, smart electronics and increased energy efficiency. Whether you’re looking for quiet relaxation or wild fun, you'll always enjoy your pool in the warm comfort of Max-E-Therm.

For indoor or outdoor installations on pools and spas. Features include an LED temperature readout with dual thermostat controls, temperature safety lockout, and 6-position control panel. PMG burner technology requires no outdoor draft hood. Proven Dura-Glas rust-proof construction with plastic manifold and PVC union connections.


  • 400,000 BTU Natural Gas Heater
  • High efficiency rating makes the Max-E-Therm extremely economical to operate.
  • Specially designed fueling and ignition process permits faster warming of your pool and spa.
  • Easy-to-read, conveniently positioned control panel is simple to program.
  • Top-mounted control panel has large format digital display and 360 degree rotation in any direction for easy viewing.
  • Control panel indicator lights pinpoint heater or system conditions, which can save money through faster troubleshooting (if required).
  • Certified for low NOx emissions and outperforms industry standards for air pollution exhaust.
  • Heater enclosure is made of Dura-Glas an exclusive Sta-Rite thermoplastic resin that handles the heat and weathers the elements.
  • Lightweight - Lightest heater in its class Best in class energy efficiency.
  • Compact Design - Ideal for retro-fit installations.
  • Easy to Switch - Change gas sources with installation of separate orifice.
  • Lower Operating Costs - 84% efficiency rating - rated first in its class for highest energy efficiency.
  • Custom or Retrofit - Direct-connects to Sta-Rite System:3 Mod Media filter or easily fits other systems.


  • Brand: Pentair
  • Sub Brand: Max-E-Therm
  • Item: Pool and Spa Heater
  • Type: High Performance
  • BTUH Input: 400,000
  • Gas Type: Natural Gas
  • Flow Rate: 120 gpm
  • Phase: 1-Phase
  • Voltage Rating: 120/240 VAC
  • Water Connection: 2-Inch
  • Control Type: Digital
  • Cabinet Depth: 31.69 Inch
  • Cabinet Height: 30.03 Inch
  • Cabinet Width: 25.15 Inch
  • Frequency Rating: 60 Hz
  • Standards Approvals: CSA Certified, Eco-Select