Jacketed Firebox Hot Oil Heaters

CEI Jacketed Firebox Hot Oil Heaters

Hot oil heaters, also referred to as thermal fluid heaters, or thermal oil heaters, heat thermal fluid that is engineered for heat transfer applications. Thermal fluid heaters are safer and easier to maintain than boilers. The heated thermal fluid exits the hot oil heater and is circulated through heat transfer piping, transferring heat to end user equipment such as asphalt storage tanks. The thermal fluid then returns to the heater, completing the hot oil circuit.

Proven dependable and durable since 1969, jacketed firebox hot oil heaters from CEI heat and circulate heat transfer oil for heating asphalt tanks, fuel preheaters, and other equipment. This highly-efficient design is available in outputs from 1.2 to 10 million Btu/hour, covering a range of applications from asphalt plants to bulk liquid storage terminals.

Operation & Features

CEI Jacketed Firebox Heater Operation

Full-Modulation Burner:

The full-modulation burner conserves fuel, reduces temperature overshooting and eliminates constant on-off burner recycling.

Jacketed Firebox:

The jacketed firebox has a smooth inner surface that is easily cleaned. It efficiently conducts heat to its outer surface. The burner fires into the firebox, where hot burner gases circulate and then enter the heat exchanger.

Heat Exchanger:

Burner gases entering the heat exchanger pass through a set of densely-packed tubes. Each tube has a special turbulator fin inside of it to stir the flow of burner gases through the tube.

The fin increases heat transfer efficiency in two important ways. First, it increases the velocity of burner gases passing through the tube, increasing heat transfer.

Second, the fin serves as a secondary heat transfer surface. Heat transfer from the fin to the tube wall is actually greater than heat transfer from the burner gases to the tube wall. All these factors add up to highly efficient heat transfer and less fuel consumption.

Flow of Heat Transfer Oil:

Oil enters the heater through the heat exchanger. A series of horizontal baffles forces the oil laterally around the tubes, providing even heat transfer throughout the flow pattern.

Oil exits the heat exchanger and then flows around the firebox in a spiral pattern. The spiral flow around the firebox maximizes heat transfer efficiency and eliminates hot spots for long life operation.

Centrifugal Pump:

The centrifugal pump circulates heat transfer oil through the heater and its heating circuit. Viton shaft seal rings provide a reliable seal with virtually no leakage.

UL-rated, NEMA 4 Control Panel:

The UL-rated, NEMA 4 control panel is the nerve center of the heater’s temperature control and safety systems. Compliance to UL standards not only assures you of the quality of the electrical system, it also puts your insurance company at ease, potentially bringing you lower premiums. The NEMA 4 enclosure provides watertight protection against splashing water, hose-directed water, rain, sleet, snow, ice, dirt, and windblown dust.

Panels that meet CSA specifications, and other NEMA standard enclosures are available optionally.

Temperature Controllers:

Two microprocessor-based controllers provide control over output temperatures. The Temperature Controller regulates the flow of fuel and combustion air to the burner to efficiently maintain the temperature set point on the controller.

The High Media Temperature Limit is a safety control. It will shut down the burner if the heat transfer oil reaches the temperature limit set on this controller.

Flame Monitor:

The flame monitor is a microprocessor-based burner management control system. The monitor provides proper burner sequencing, ignition and flame monitoring protection. In conjunction with limit and operating controls it sequences the burner/blower motor, ignition, and fuel valves to provide for proper and safe burner operation. Other features include:

  • Self-diagnostic for safety and reliability.
  • Non-volatile memory retains information even when power is interrupted.
  • Microprocessor-based for accurate timing, comprehensive diagnostics and precision control.

Digital Annunciator:

The digital annunciator visible on the front of the control panel displays heater status at all times. Any safety limit that is exceeded will immediately shut down the burner. The cause will be clearly displayed on the LCD screen, reducing down time and assisting CEI Service personnel diagnose any heater issues remotely, if necessary.

Wireless Monitoring Systems:

Wireless monitoring systems are optionally available for additional convenience and reduced down time. These systems communicate any heater shut-down issues to your cell phone, so you will know what’s happening with your heater, no matter where you are.


The heaters operate on natural gas, LPG, or No. 2 commercial grade fuel oil, depending on the burner used. An optional combination burner allows switching between two different fuels.

  • CEI Jacketed Firebox Hot Oil Heater with optional wireless monitoring system
    Jacketed firebox hot oil heater with optional wireless monitoring system.
  • CEI Jacketed Firebox hot oil (thermal fluid) heater
    Jacketed firebox heater with black paint and embossed aluminum skin.
  • CEI Jacketed Firebox Hot Oil Heater with optional manifold and ultra low-NOx burner.
    Jacketed firebox hot oil heater with optional stack heat exchanger, Ultra-Low NOx burner and manifold for multiple hot oil circuits

Available Options:

  • Low-NOx burners (30ppm).
  • Ultra low-NOx burners (less than 9ppm).
  • Stack heat exchangers for boosting fuel efficiency.
  • Optional burner management system utilizes an exhaust stack O2 sensor to maintain hot oil heater operation in adverse climates. Reduces fuel consumption and tunes burner automatically.
  • Sock filters for longer fluid and pump life.
  • 7-day time clock.
  • Non-standard voltage (525/60, 380/50)
  • ASME code stamp.
  • CSA approved panel.
  • CRN stamped coils.
  • Class I Div. I or Class I Div. II explosion-proof components.
  • High-temperature (550°F) operation.


The heaters are very easy to maintain. Components are easy to reach. Replacement parts are readily available from CEI’s large parts inventory. We back our products with worldwide parts & service support.

  • CEI Asphalt and Fuel System
    CEI hot oil heaters can be optionally installed on the goosenecks of portable storage tanks.
  • CEI hot oil heaters
    Twin-heater thermal fluid heat transfer system used in a storage terminal application.
    In this application, the hot oil heater provides heat to a CEI asphalt barrel melter and two CEI asphalt storage tanks.

For additional information on hot oil heaters, please contact Heatec, Inc — an Astec Industries company