After long-term use, millboard often contains active mould spores. Disinfecting and replacing affected surfaces will prevent mould from contaminating the indoor air as well as downstream HVAC components.


Heating, ventilation, and air-conditioning (HVAC) systems are used for heating and cooling residential, commercial, and industrial buildings.

Aside from helping ensure the comfort of those residing in these spaces, HVAC can also help dilute airborne contaminants by providing fresh outdoor air. HVAC systems generally have essential design elements, like an outside air intake and an air handling unit consisting of fans, heating and cooling coils, and air filters. There’s also an air distribution system and an air exhaust system. Part of the air distribution system is the duct system, which provides a controlled path for the air to flow throughout the home, commercial space or factory. It consists of a branching network of round or rectangular tubes, which may be made from materials like sheet metal, millboard, and insulated plastic throughout the building.


An integral part of the duct system is the electric duct heater, which uses electricity to warm the air that passes through a duct. It consists of a heating element that converts the electricity into heat through resistance.

The resulting heat is transferred by conduction or convection to the air passing through the device. These duct heaters are used for space, supplementary, and primary heating applications. These devices monitor temperatures and automatically modify heat output accordingly to maintain the ideal temperature of the open coil element. In addition, electric duct heaters can be programmed in such a way that they can heat the area at a specific point in time.

This results in efficient heat transfer without wasting energy as the room or space is only heated for the required times. Electric duct heaters in HVACs can also complement the heating of buildings by preheating fresh air or returned air. Most modern electric duct heaters have a modulating controller that facilitates operation in extremely low airflow without compromising performance.


These devices may be installed in the ceilings of office buildings, schools, churches, accommodation areas of sea-going vessels, and other facilities.

Duct heaters are relatively easy to install, whether for a new project or to replace an old one, because every heater is designed according to a current dimension, wattage, and current. However, installation should always be done by a qualified professional like our team at Air Restore.

Most electric duct heaters in HVACs have features like an air flow cut-off switch that can ensure airflow across heating elements occurs evenly, allowing the system to adjust if one element receives too little air. Another typical feature is an automatic, primary thermal cut-off that will stop the unit whenever the temperature limit has been reached.

Our qualified team of technicians can assess and provide you with a detailed scope of work for your heater bank upgrade including before and after certifications so you can be sure it has been completed to an accredited level.