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Pentair 461021 MasterTemp ASME HD Commercial Heater, Natural Gas, Cupronickel, 400K BTU

SKU 461021
TradeGrade Exclusive - Request availability & checkout.

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Ultra-High ASME® certified performance in a compact, quiet, and eco-friendly design for your commercial application.
  • The bronze header design allows easy access to the thermal regulator and bypass valve service without special tools.
  • Upgrades to the thermal regulator include a governing stainless steel sleeve for better wear protection.
  • All internal components of the bronze header are now plastic for lightweight, corrosion, and wear protection.
  • The ignition Control Module includes more diaphragm spring force for better gas control and robust operation.
  • The fuller pre-mixed system with a highly efficient air and gas mixture allows for faster heat-up times.
  • Efficiencies up to 84%
    Support Documents


    • Brand: Pentair
    • Application: Indoor, Outdoor, Pool, Spa
    • BTU Output: 400000 British thermal unit
    • Cabinet Depth: 32.61 inch
    • Cabinet Height: 28.15 inch
    • Cabinet Width: 23.02 inch
    • Commercial, Residential, or Professional: Commercial
    • Control Type: Digital
    • Weight: 149 pounds
    • Flow Rate Max: 120 gal/min
    • Flow Rate Min: 120 gal/min
    • Frequency Rating (Hz): 60
    • Fuel Type: Natural Gas
    • Green or Energy-Efficient Product: True
    • Phase: Single
    • Standards Approvals: ASME Certified
    • Voltage: 120V, 240V
    • BTU Input: 400000 British thermal unit
    • Gas Connection: 0.75 inch
    • Tubing Material: Cupro Nickel
    • UPC Code: 788379858278

    MasterTemp ASME Commercial Heater Models:

    • 461000 Natural 200 ASME
    • 460771 Natural 250 ASME
    • 461020 Natural 250 ASME HD
    • 460775 Natural 400 ASME
    • 461021 Natural 400 ASME HD

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    Please Note: Pentair ‘TradeGrade Exclusive’ products require contacting us to purchase. Please use the request form above or Contact Us page; we can provide product details, availability, pricing, purchasing options, etc.

    Disclaimer: Professional installation is required (not included). Proof of installation by a trained technician is required to validate the factory warranty.

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