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Improve your comfort system's efficiency with these equipment add-ons

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ESC Direct Vent Cast Iron Gas Boilers

Ideal for installations where chimney venting is not possible' industry standard tapping locations permit ease of replacement for thousands of existing boiler installations.

  • Electronic ignition
  • Easy' intelligent IQ Control System™
  • Outdoor reset available – increases efficiency by 15-20%
  • Rear jacket panel of boiler is flat with no protrusions' simplifies transport and enables flush installations
  • Reliable' American-made cast iron heat exchanger can accept return water temps as low as 110°F
  • Intelligent Hydronic Control Combines aquastat' relay' and other ignition functions into a single module
  • IQ Option Panel Enables the easy plug & play installation of optional features such as outdoor reset' LWCO' and high limit
  • Optional Touchscreen LCD displays all boiler settings' diagnostics' and troubleshooting in sentences' not codes
MODELInput MBtuHOutput MBtuHAFUEDimensions
Water Content
ESC360.0 52.0 85.5 41x12.75x33 2.00 250
ESC491.0 78.0 85.4 41x15.5x33 3.00 300
ESC5121.0 104.0 85.3 41x18.5x33 4.00 350
ESC6152.0 130.0 85.2 41x21.5x33 5.00 410
ESC7182.0 156.0 85.0 41x24.75x33 6.00 460
ESC8212.0 180.0 84.5 41x27.75 7.00 510
ESC9243.0 206.0 84.0 41x30.75x33 8.00 560

Warranty Information

  • All Parts for 12 months -
  • Heat Exchanger - Limited Lifetime

Available Documents