Direct Unit Heaters: Direct Benefits
Direct unit heaters are less commonly used in greenhouses than their indirect unit heater counterparts.
Simply put, the typical indirect fire unit heater has an exhaust system that takes the byproducts of combustion outside of the greenhouse. That means that heat, water, and exhaust gasses (including CO2) are vented outside of the growing area. As a result, heat energy is lost to the outside environment which means less heat is provided to the greenhouse per unit of gas consumed. This leads to higher gas consumption compared to higher efficiency heat sources like high efficiency boiler systems and direct fire unit heaters.
Direct fire unit heaters exhaust directly into the growing environment. That means that all of the heat energy generated from burning gas is retained in the growing environment. That also means that the other combustion byproducts stay inside of the greenhouse as well. For this reason, many growers call these heaters “CO2 Burners” and utilize them in this way. The result is a heater that has up to 99% efficiency and can help reduce gas bills.
As with all technologies, the application of the technology often matters as much as the technology itself. The best fit application for direct fire unit heaters is as a secondary heat source; they can be paired with a boiler system or with their less efficient indirect unit heater counterparts. They also require some degree of ventilation to ensure that the burner continues to burn with fresh air. Direct fire heaters can also be used as primary heating sources in some situations as well as for supplemental CO2.
Direct fire heaters can also address a common challenge when switching from HPS lighting to LED lighting, the reduction in radiant heat and associated drop in leaf temperatures. Due to their high energy efficiency and supplemental CO2 production, they are an excellent way to supplement heat when making the switch to LED grow lights.
The Holland Heater direct fire heater provided by Total Energy Group is known for its durability, works with propane or natural gas, has up to 410,000 BTU capacity, and up to 99% efficiency.
At Total Energy Group, we have been supplying and servicing direct fire heating systems to growers for over 25 years. Reach out today.
