My 20 year old furnace broke down. I want a new one. I would like some advice on the type, efficiency, capacity, and brand I should get.

Asked by Chin
Palo Alto, CA

I did some Googling and understand that efficiency (AFUE) and capacity (BTU) are two most important factors. My house is one floor 3-bedroom, 2 baths, ranch, 1600 square feet. Have plan to do extension in the future to add 1-2 more rooms and expand the kitchens, but not immediately. I am in California, and thus have a very mild, dry climate, with a temperature swing from day to night


Gregory Caplan

Answered by Gregory Caplan

Jamaica Plain, MA

Green Home Carpentry & Design

November 13, 2013

Hello, Assuming you will be using a gas furnace, I would suggest a sealed combustion rather than "atmospheric" unit. Further you can benefit by installing a furnace with proportional control so that it can modulate the size of the flame like your gas burner on your range might. As far as expanding space goes, pleased consider that one of the most primary factors in sustainability is size.

Tagged In: green furnace, replacing furnace, sizing the correct furnace

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