What should the air intake source for industrial air heaters ideally be?

For industrial air heaters, the ideal air intake source is from outdoors. This is crucial because outdoor air is less likely to carry contaminants or pollutants that may be present in indoor environments. By using fresh air from outside, the heater can ensure a higher quality air supply, which is essential for optimal combustion efficiency and air quality within the heating system.

Using air from conditioned spaces, for instance, can lead to the deterioration of indoor air quality, as well as impact the efficiency of both the heating and cooling systems. Similarly, recirculating indoor air may reintroduce contaminants and reduce overall effectiveness. Drawing air from the attic could also be problematic, as attics can contain moisture, heat, or degraded air that could pose risks to both the heating system and the space it serves. Therefore, sourcing air intake from outdoors is the best practice for ensuring efficiency and safety in industrial air heaters.