The 2007 Energy Security and Independence Act gave the Department of Energy the power to set regional standards for heating and cooling systems. As of May 1, 2013 the DOE will make it illegal for 80% efficient furnaces to be installed for new construction or retrofits.

The biggest change for the customer is that the exhaust for 90 percent or greater furnace is different that the 80 percent. 80 percent furnaces are non condensing. 90% and greater efficiency furnaces are condensing furnaces. They omit water vapor and carbon dioxide, that will rust the metal exhaust used to vent 80 percent furnaces. So, we have to use PVC to exhaust 90% and greater efficiency furnaces. We aren’t able to adapt to the metal exhuast, due to either bends or a hot water tank being connected to the furnace exhaust.

Furnaces located in a garage, attic, crawlspace or on an outside wall shouldn’t have too much of an issue. But, furnaces that have no outside access are the ones that will have the extra added cost of trying to hide the PVC used to exhaust the new higher efficient furnace. We will have to run the exhaust outside with a slope for the water to drain from the exhaust.

If you have an existing 80 percent furnace that you are thinking of changing out for the same, now is the time to do that, before you won’t be able to.