A category 1 natural gas furnace typically has an air temperature rise of what range?

A category 1 natural gas furnace typically operates with an air temperature rise in the range of 60°F to 120°F. This range is characteristic of furnaces that are designed to vent products of combustion to the outside atmosphere and are categorized by their specific construction and exhaust methods.

The temperature rise refers to the difference between the return air temperature entering the furnace and the supply air temperature exiting the furnace. A rise of 60°F to 120°F indicates the furnace is effectively transferring energy from the combustion gas to the air used for space heating, which is essential for operational efficiency.

This specific range is important for ensuring safety and performance, impacting both the comfort of the space being heated and the overall efficiency of the heating system. A rise below 60°F may suggest inadequate heating performance, while a rise above 120°F could indicate that the furnace is operating under excessively high conditions, which may lead to safety concerns or inefficient operation.