High Efficiency Furnace Exhaust

After the first stage the hot exhaust gasses are cycled through a second combustion stage resulting in exhaust with very little heat.

High efficiency furnace exhaust.

Condensing gas furnaces achieve their high levels of efficiency by adding another step to the fuel burning and venting process. These pvc pipes are connected to the furnace and expelled outside. Other aspects of high efficiency furnace venting. When these gases meet the cold air they condense and create condensate.

This process creates condensate or moisture from the furnace s heat exchanger. The pvc pipes are used for air intake exhaust gas and to remove the corrosive condensation resulting from the combustion process. A conventional furnace vents these combustion gases through a vertical exhaust system that is attached to the furnace. They include a second heat exchanger that reclaims additional heat from the system s exhaust gases before they are vented away.

As was noted previously the exhaust gases from a high efficiency furnace are much cooler than a conventional furnace. A high efficiency furnace uses a different type of venting system because it extracts the heat that remains in those combustion gases before venting the resultant mixture of water and carbon dioxide. If not installed correctly or checked regularly problems in these pipes can affect the operation of the furnace itself. It is classified as type bh venting.

Venting for high efficiency gas furnaces materials due to the condensing nature of a high efficiency furnace its venting must be made of a material that is resistant to corrosion. High efficiency condensing furnaces have two stage combustion to extract as much heat energy as possible from burning gas. In a conventional furnace the hot exhaust discharge has more time to exit a chimney flue and move away from a home or business before it condenses.