High Efficiency Gas Furnace Exhaust Temperature

Mid efficiency furnaces have an afue annual fuel utilization efficiency of 80 and high efficiency furnaces have an afue of 90 98.
High efficiency gas furnace exhaust temperature. High efficiency or condensing furnaces exhaust the combustion gases and bring in fresh. There are several other important aspects of high efficiency furnace venting. In high efficiency models the lower temperature of the exhaust can allow moisture a by product of combustion to condense in the flue especially when outdoor temperatures drop into the 20 s or below. Vent pipe blocking the exhaust flow.
Traditional gas fired forced air furnaces produce hot combustion exhaust gasses and therefore need metal vent pipes or chimneys. The pvc pipes are used for air intake exhaust gas and to remove the corrosive condensation resulting from the combustion process. Other aspects of high efficiency furnace venting.