Today we get a new AC unit and furnace. This is the largest expense we have made on our home in 20 years, but it is sorely needed. Our furnace is 30 years old and every winter I wonder if it will last another season. A new one will be safer and will be much more energy efficient. Also, although I made it through last summer without AC, the basement gets so damp without it that I had some Christmas items damaged by mildew. Mr. Marple doesn't like to be hot, so a new AC should help him have a more enjoyable summer.
I can tell you what a great feeling it is to have a new well pump. You will have that same feeling with your new furnace. You will breath are great sigh of relief when it comes time to heat your house next wi**er season.