Logo Neptronic

Open Coil Electric Heaters

Open Coil Open Coil - Open Coil
  • Excellent heat dissipation
  • Minimal pressure drop
  • Fast response time
  • Up to 40kW / sq.ft.
HECB Networkable Controller Open Coil - HECB
  • BMS Integration
  • Save energy
  • Monitor alarms
  • Remote diagnostics
Patented EAS Open Coil - EAS
  • Patented Electronic Airflow Sensors (EAS)
  • No mechanical switch required
  • Detects as low as 100 FPM
  • Automatic load shedding
Installation Options Open Coil - Options
  • Slip-in, flanged, or round
  • Vertical or horizontal mounting
  • Selectable control panel configurations
  • Selectable enclosure rating
  • Open Coil

    Electric Heaters
  • HEC / HECB

    Heater Controller
  • EAS

    Patented Electronic
    Airflow Sensors
  • Options

    Mounting & Control
    Panel Options
Open Coil – Electric Heaters

Open Coil Electric Heaters

Most popular in the industry

Suitable for most standard HVAC
ducted systems

Heating capacities from 0.5 to 1000kW
(larger loads also available)

Up to 40kW per sq.ft

Integrated HEC controller

Patented EAS
(Electronic Airflow Sensors)

Open Coil Elements Options

Grade C NiCr60 (60% Nickel and 16% Chrome)

Grade A NiCr80 (80% Nickel and 20% Chrome)


For applications in a humid environment, we recommend the optional NiCr80 (grade A) elements.
They are composed of 80% Nickel and 20% Chrome (does not contain iron).
This will allow a maximum operating temperature of 2 100˚ F (1 150˚ C) and installation where condensation may be present in the air duct.

  • HECB - Networkable Controller
  • HEC - Standard Controller

Patented EAS

Electronic Airflow Sensors (US Patent 7,012,223)

Accepts any industry standard input signal
In this example there is a demand for 6kW, which requires a minimum 500FPM.

Precise air velocity readings (as low as 100 FPM)
Using both temperature sensors and other known values, the HEC controller calculates the precise air velocity. These readings can go as low as 100 FPM, which is excellent for VAV applications. In this example it is 200 FPM.

Load shedding: overrides demand if velocity is insufficient
Protects elements from overheating and eliminates unnecessary shutdowns if velocity is insufficient for actual demand. In this example, the demand of 6kW requires a minimum 500 FPM, but the HEC controller detected an actual velocity of 200 FPM. The HEC controller lowers the output to 2 kW for 200 FPM. As opposed to air flow switches that simply shutdown the heater.

Additional overheat protection.
If heater element is too hot or if there is no air flow, electronic shutdown of the heater prevents cycling of the contacts. This is in addition to the thermal cut-off.

No air flow switches required
The velocity is calculated using the factory installed temperature sensors and built-in algorithms. Using the temperature readings, the HEC controller also automatically determines the orientation of the air flow. This saves cost and reduces labour as expensive air flow sensors are not required and there is no need to fine tune air flow switch positioning.

  • Installation Options
  • Control Panel Options
  • Enclosure Ratings


For entire frame to be inserted in the duct


For heaters to be an integral part of the duct work

Round collar

For round duct systems of 6" to 24" (152mm to 609mm) diameter

No need to define air flow orientation  Designed for Vertical or Horizontal Mounting



Bottom Control Panel

for easy installation and maintenance

Insulated Control Panel

for high duct temperatures. Insulated material, 1” thick, is installed between the panel

Remote Control Panel

for installing the control panel remotely from the heater or in a separate room

Indoor Use

*NEMA Type 1 (IP10)

Incidental contact

Falling dirt

NEMA Type 12 (IP52)

Incidental contact

Circulating dust

Falling Dirt





Light splashing of liquids

Indoor / Outdoor Use

NEMA Type 4 (IP56)

Incidental contact

Falling dirt




Windblown dust

Splashing water

Hose-direct water

External formation of ice

NEMA Type 4X (IP65)

Incidental contact

Falling Dirt




Windblown dust

Splashing water

Hose-directed water


External formation of ice