What happens to gas input ratings if no adjustments are made when operating above sea level?

When gas appliances are operated at elevations above sea level without making any necessary adjustments, the gas input ratings will decrease efficiency. This occurs because the atmospheric pressure is lower at higher elevations, resulting in less oxygen available for combustion. Gas appliances are typically calibrated for operation at sea level where the atmospheric pressure is standard.

As a result, when these appliances are used at higher elevations, they may not burn the gas as efficiently, which can lead to incomplete combustion, decreased heat output, and possible operational issues. Therefore, to maintain effective and safe operation, adjustments in the gas input ratings are necessary to compensate for the reduced oxygen levels and ensure that the appliances function optimally.