Sterling separated combusiong heaters draw combustion air from outside to ensure that the unit will always have plenty of fresh clean air. The fresh air supply reduces common concerns about dusty, dirty, or high humidity applications. SF separated combustion heaters are great options for buildings with negative pressure, greenhouses, auto repair and parking garages, and are also used to more safely heat areas where indoor flammable gasses may be present. Sterling SF heaters also include a concentric vent kit which allows the heater to be vented to the outside wall with only one pipe as shown in the picture below. This venting method heats the outside combustion air with the exhaust pipe before entering the heater which can increase overall heater efficiency by as much as 10%. The vent kit includes the concentric vent box, inlet air screen, deflector box, and vent terminal (piping not included). The concentric vent kit can used for both vertical and horizontal venting.
Other unit heaters available today are designed with the old clamshell style heat exchanger, positioned above ribbon-style burners. These are the most common points of failure, especially in the greenhouse environment. Heat exchangers invariably fail at the points where manufacturing processes have weakened the metal by stamping, crimping and welding. Sterling SF gas heaters are equipped with a tubular heat exchanger which consists of smooth, continuous tubes are formed in a serpentine shape and then placed in parallel rows. This type of heat exchanger has no stress points, no points where the metal has been compromised making it more durable than a similar clamshell heat exchanger and allowing the unit to be equipped with in-shot burners.
Single Stage, Direct Spark Ignition, 100% Shutoff with Continuous Retry - Utilizes a single stage combination gas control with built-in ignition control. Gas is lit with an electronic direct spark igniter on call for heat. Most gas heaters have pilot flames which must stay lit for the heater to perform. With a direct spark igniter, you don't have to worry about drafts putting out the flame. It comes on only when heat is needed every time heat is needed! 115 volt power supply and 25 volt controls.
Power Vent System
Every Sterling SF natural gas or propane heater features a fan powered vent exhaust. Power vents force heater exhaust fumes outside of the heated structure, and allow the heater to be vented vertically or horizontally. Horizontal venting keeps heat from escaping out of the vent pipe when the heater is not running. This is especially important when using gas powered heaters in greenhouses. Conventional vents use natural air drafts (chimney effect) to expel exhaust fumes. Unvented gas heaters leave these fumes in the greenhouse which can be harmful to plants.
Flame Rollout Switch - will shut off the gas supply to the heater in the event of flame rollout.
Pressure Switch - will shut off the gas supply to the heater in the event of a problem with the venting system.
Download Sterling SF Gas Heater Installation Manual
Clearances to Combustibles