markviii wrote:Excellent point. He already mentioned that the furnace was ~30 years old. I have seen some older furnaces that were way oversized, short cycled, etc. Add in some poorly insulated duct work and it is easy to see how a constantly burning coal stove (and a very efficient one at that) would edge out the oil furnace in operating efficiency.
It turns out, my furnace is sized just about right. Mainly because when it was first installed, the addition with the three bedrooms and bathroom were not on the house, when they were added afterwards, turns out the furnace is the right size as luck would have it.
I don't know what short cycled really means or how to check for it. I just assume it means the furnace runs for too short a time and cycles on and off too often. How do you tell?
Hmm, poorly insulated duct work? I'd say the UNinsulated duct work I have may be a major contributor!
Now one thing I will disagree with you on, you say "edge out the oil furnace in operating efficiency"; I'd say "blows away the oil furnace in operating efficiency"! Of course, I show no bias here do I? ... LOL