In early October 2017 we added a new option to the heating section for existing (base) systems. You can now determine if a boiler or furnace is a condensing unit as opposed to a conventional gravity or power vented unit. Condensing units have a much higher AFUE, ranging between 90 and 98. But since 80 AFUE furnaces are still legally produced today, we had to assume the worst possible system was installed in the existing home. Since condensing units are really simple to identify (look for two PVC pipes coming out of the unit as opposed to a single steel vent), the user can now pick between a conventional system and a condensing system.

The new "Is Condensing" button is only available for Gas and Propane Furnaces and Boilers:

Regardless of the model year of the equipment, if you choose Yes for "Is Condensing", the energy model will default to an AFUE of 90 if you use No Bills. If you have entered simple or detailed utility bills, the calibration will pick an AFUE between 90 and 96 depending on the Model Year and how much energy the home uses. Note: the Model Year is required in order for the Is Condensing button to work properly.

If you choose No for "Is Condensing", the AFUE will default to a maximum of 78 or lower depending on the utility bill calibration in the same way that it always had before the Is Condensing button was added.

The condensing button is only available on the base side, since you should have the AFUE of a model you are recommending or installing for the improved side.

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