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.
High efficiency furnace exhaust.
This high efficiency venting system must be installed when you install the new furnace.
They include a second heat exchanger that reclaims additional heat from the system s exhaust gases before they are vented away.
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.
When these gases meet the cold air they condense and create condensate.
The pvc pipes are used for air intake exhaust gas and to remove the corrosive condensation resulting from the combustion process.
After the first stage the hot exhaust gasses are cycled through a second combustion stage resulting in exhaust with very little heat.
Condensing gas furnaces achieve their high levels of efficiency by adding another step to the fuel burning and venting process.
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.
As was noted previously the exhaust gases from a high efficiency furnace are much cooler than a conventional furnace.
It is classified as type bh venting.
High efficiency condensing furnaces have two stage combustion to extract as much heat energy as possible from burning gas.
Other aspects of high efficiency furnace venting.
If not installed correctly or checked regularly problems in these pipes can affect the operation of the furnace itself.
This process creates condensate or moisture from the furnace s heat exchanger.
These pvc pipes are connected to the furnace and expelled outside.