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CTM HOTflow® Engine Heater

An efficient forced circulation system that allows for a variety  of small engine applications.

Despite its small footprint, efficient forced circulation allows the HOTflow® CTM system to heat engines up to 20 liters in displacement, allowing for a wide variety of weather-protected small engine applications. Multiple options are available, including UL/C-US listed and CE-compliant models.

The CTM’s inlet and outlet may be reoriented at 90° increments to accommodate heater plumbing. The included mounting kit is ideal for most installations; an optional vibration isolation kit is also available. Forced circulation provides uniform heat throughout the engine, reducing component maintenance and offering significant energy savings - resulting in end-user utility cost reductions up to 35%*.

*Savings are dependent on local utility rates and installation variables.

Not intended for hazardous locations.

Heating Information

Primary Heating

  • Water
  • Coolant Mix

Primary Heat Power

  • 1 kW
  • 1.5 kW
  • 2.5 kW

Power Specifications

Power Sources

  • AC, Single-Phase, 60 Hz
  • AC, Single-Phase, 50 Hz


  • 120
  • 240

Power Connectors

  • NEMA Plug
  • Euro Plug (Schuko)
  • Hardwired

Temperature Control

Primary Temperature Control

  • 100–120 °F (38–49 °C)

Primary High Limit Temperature

  • 300°F (149°C)

Mount Types

  • Bracket

Inlets / Outlets


  • 0.625” hose barb (15.9 mm)


  • 0.625” hose barb (15.9 mm)

Ingress Options

System Ingress

  • IP44


  • CE-compliant models available
  • UL-C / US listed

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