6.2.4 Describe condensing technology for space and water heating and its limitations

• In condensing furnaces, the combustion process is managed so that the exhaust cools enough to allow many by-products of combustion to condense
• These are drained off, allowing the final exhaust gases to leave the furnace at low temperature.
• This process allows more heat to be extracted and sent into the home rather than up the chimney
• max 99% rather than 85% for non-condensing
• The condensate for oil is difficult to manage because it is much more corrosive than that of natural gas or propane.