The first floor has 75,000 btu furnace and heat-load calc says I need about 50.  Maybe that is why the furnace heat cycle is short, but the house is comfortable.  Question 1:  The thermostat is located right above the return grill.  Would it be better to relocate the thermostat to the cooler spot in the house and adjust local temperature with duct and register baffles?  Question 2:  Because, I am guessing, heat cycle is short (about 3-4 minutes for 1500 square feet 1st floor), the by-pass humidifier (Aprilaire model 445) does not throw enough moisture in the air.  The water flows only when flame turns on.  If I change the humidistat to the automatic humidistat, would it really add 50% more humidity to the air as claimed?  How would powered humidifier help?  I tried leaving the furnace fan and the humidifier water pump “on” all the time and this has increased the humidity, but I stopped this in case this leaves too much moisture in the ducts and encourage mold.  Question 3:  The second floor got the attic mounted furnace.  Originally I wanted to put the furnace in the basement, but all 3 estimates discouraged this, and the estimate for the basement situated duct work was very high.  So the return is in the hall ceiling.  My guess is that this would take the return air from the first floor.   The thermostat is on the hall wall.  The contractor said this would work fine.  My assumption says otherwise.  Wouldn’t it more accurate to have the thermostat in one of the bedrooms?  The relocation work would be minimal (no sheetrock yet).  Also, is there a way to install a humidifier to the attic furnace in the hall closet?  Sorry about the length of this question.  They are the result of several months of musing.  Thank you all in advance, and happy holidays.