To protect workers on the job site, business owners and contractors choose between direct vs indirect heaters. Both help keep work environments comfortable, efficiently heat the air, and come with their own benefits. Choosing the right type of heater depends on where you’re using the unit and the nature of the job. This article compares directly vs indirect heaters and where they work best.
Direct fired heater
With direct-fired heaters, the flame comes into contact with the air. One of the advantages of a direct fuel-fired heater is that they are less expensive and more efficient to run. 100% of the propane or natural gas used is converted into heat. They are designed to heat open spaces and should not be used in enclosed areas with no means to remove toxic fumes, such as ductwork, tanks, vaults, and silos.
Direct fired heaters work well in a large or well-ventilated space, such as:
- Construction sites
- Open-air buildings
- Large venues and sports arenas
Remember, safety should always be the top priority when choosing a direct-fired heater. If you can use one for your job site, you can reap the benefits of cost savings and contribute to a smaller carbon footprint.
Indirect fired heaters
Think of how a furnace operates, and you’ll have an idea of how indirect fired heaters work. Compared to direct-fired heaters, these units have a bit more of a complex system. They’re powered by propane, natural gas, diesel, or oil and draw air through intake vents. Once the air passes over the burn chamber, it’s heated and powered into a building through the ducts. Any unwanted fumes are expelled through a chimney.
Indirect fire heaters are ideal for:
- Warming indoors and tight spaces with an exhaust outlet
- Job sites that can benefit from less humidity, like concrete curing
- Environments that require no combustion by-products in the airstream
A setback with an indirect-fired heater is that they are less fuel-efficient when compared to direct fire heaters. However, in many instances, an indirect fire heater is the only option for safety and expelling dangerous carbon monoxide fumes.