Furnace Makeup Air Requirements

Our duct furnaces can be ordered with several different options so they fit your specific requirements.

Furnace makeup air requirements.

Several options are also available for the outdoor and indirect indoor make up air unit. The real requirement is that makeup air must be provided if it s needed. To burn 1 cubic foot of gas approximately 1 000 btu for natural gas requires 10 cubic feet of air for perfect combustion figure 2. In homes with naturally drafted fuel fired appliances like a boiler inside the envelope kitchen range hoods that exhaust more than 400 cu.

By glenn mathewson issue 287 kitchens baths. Department of energy a defining feature of high efficiency furnaces is sealed combustion a process by which outdoor makeup air is piped directly into the burner. With a make up air unit that same 10 f air can be tempered to 50 f. Of air per minute require makeup air so they don t depressurize the home and draw combustion gases from the appliance into the living space.

According to the u s. Makeup air shall be mechanically or naturally provided makeup air systems shall be equipped with not less than one damper gravity dampers electrically operated damper that automatically opens when the exhaust system operates 26 2015 requirements adopted in pa. The makeup air system consists of a make up air damper mounted on the return air duct of an hvac system and an intake air hood installed through an exterior wall to allow outdoor air into the home with the two being typically connected by installer supplied standard 6 galvanized sheet metal pipe. Ten cubic feet of air contains 2 cubic feet of oxygen and 8 cubic feet of nitrogen and other gases combined with water vapor.

Makeup air for kitchen exhaust. Likewise if the outside air temperature is 10 f then the ventilation fan is bringing in 10 f air. Exhaust hood systems capable of exhausting in excess of 400 cfm 0 19 m 3 s shall be provided with makeup air at a rate approximately equal to the exhaust air rate. In addition our indoor outdoor direct fired make up air unit is an efficient way to supply tempered make up air to your space.

The minnesota mechanical code is a combination of chapters 2 to 15 of the 2006 international mechanical code and minnesota s amendments. Such makeup air systems shall be equipped with a means of closure and shall be automatically controlled to start and operate simultaneously with the exhaust system. This means the heating system wouldn t be required to work any harder than is necessary nor would it waste energy.