Open coil heaters are widely used in HVAC (Heating, Ventilation, and Air Conditioning) systems to provide fast and efficient electric heating of air. They work by passing an electric current through exposed resistance wire-usually made of Nickel-Chromium (NiCr)-which heats up quickly due to its high resistivity.
Working Principle in HVAC Systems:
Air Flow Initiation
The HVAC system's blower or fan pushes air over the open coil heater assembly.
Electrical Heating
When current passes through the resistance wire, it rapidly heats up to temperatures as high as 1100°C (2012°F).
Direct Heat Transfer
Because the coil is open and exposed, heat is transferred directly to the moving air with minimal thermal loss.
Warm Air Delivery
The now-heated air flows through ducts and is distributed throughout the building or facility to maintain desired indoor temperatures.
Why Open Coil Heaters Are Ideal for HVAC:
Fast Response Time – Heats up and cools down quickly for better temperature control.
High Efficiency – Open wire design ensures maximum heat transfer to the air.
Cost-Effective – Lower material and manufacturing cost compared to enclosed heaters.
Compact and Lightweight – Easy to integrate into air ducts or compact HVAC units.
Common HVAC Applications:
Electric duct heaters
Space heaters
Rooftop units
Make-up air systems
Air curtains
