Hi, first timer here. I bought this 43-year-old house last October, app 2000 sq ft, trilevel (main living level, 2 BR/bath up 7 stairs, 2 more BR/bath up 7 more stairs on top level). My heating bills last winter (2 year old Lennox AA600 80% efficiency furnace) were really high, around $300 per month during the cold weather, and I never set the t-stat above 65-66. It was pretty chilly throughout the entire house, especially on the main level. I chalked it up to poor insulation, heat rising to the top level, lots of can lights and having a bigger house than I'd had before. I did all I could without hiring professionals to tighten it up but it was a long, uncomfortable and EXPENSIVE winter. Amazingly, this summer my electricity bills have been extremely low, averaging $100 a month for 97+ degree temps, thermostat set at 75. Is it normal that it would take so much less energy to cool a house than to heat it? I have a 1-year-old Ruud AC. My furnace cycled on every 18 minutes during the winter and ran for about 10 minutes, it seemed like it ran constantly, but the AC cycles often too. It's a White-Rodgers t-stat and the widest temp swing setting it will adjust to is 1.5 degrees. I'm wondering if I need to get a new t-stat, but it seems to be working fine during the summer -- Maybe it's because all the heat rises and then is lost into the attic, and then the t-stat on the first level kicks on again??? I don't know ... I'm happy about the low AC bills, but curious why there would be such a disparity in seasonal energy costs -- does anyone have any thoughts about why this might be, or what I can do? My previous house had insulation blown into the walls and attic, and my heating/cooling bills were pretty equal. It also only had one bedroom upstairs, this house has four BR and 2 baths. Hope this makes sense, thanks.

moonmadman

Short answer: with 2000 sf, the footprint of the tri level house is likely around 700sf per level. That would translate into roughly $350. to have another R-25 blown into your attic.
$500. to get an R-38 (more or less). This is the first thing I do when I buy a house. There are no parts to wear down and no maintainence. In my present house, I added 16" of insulation and changed all of the windows and installed storm doors and the heating bills were cut in half.
RE: your a/c, it can be that you have a higher efficiency unit (13 or above), which WOULD be that much more efficient.
good luck.