Rexotherm Direct Fired Heater

Lower CFM Heaters Burn Less Fuel

CHI Companies brought in our 1,000,000 BTUH direct fired heater and the competitions 1,000,000 BTUH direct fired heater into a third party testing lab. The results showed that a lower CFM heater will use significantly less fuel per season. Heaters that have higher CFM ratings will use from 7% to 35% more fuel for the same BTUH rating.

Heat Comparison Study based on (1) 1,000,000 BTUH Heater

Cubic Feet per Minute (CFM)
CFM x 60 Minutes
CFM x 24 Hours
CFM per Heating Season (150 Days)
Difference in CFM over Season

The Rexotherm Direct Fired Heater has a higher temperature and lower CFM discharge than any other heater. The Rexotherm heater high temperature discharge gets the building up to the desired temperature quickly and then switches to a low burn cycle until the thermostat calls for heat.This has proven to be not only the most fuel efficient unit (dollars saved), but also the cleanest burning (lowest carbon monoxide).

Heat Loss BuildingThe more CFM of Cold Outside Air a heater pulls into a building, the more cold air needs to be heated, therefore the more you spend on fuel. Also, a larger CFM heater will over pressurize a building. Buildings under constructions have many leak points and a high infiltration. When a building is introduced to a large CFM heat source, the air gets either pushed out all of the existing openings or into the walls. Mold can easily form in the walls and may not be detected for years.


High CFM heaters are excellent for finished buildings, they are extremely inefficient for buildings under construction.