Shut off vents in rooms not in use?
Noticed that the upper floor is too warm and the first floor is
too cold?
Shut off vents on the upper floor to force more heat to the lower
floor?
Shut off vents on the lower floor to force more cooling to the
upper floor?
Desired more cooling in a room with a large solar exposed glass
area while all other rooms were cooling comfortably?
Found yourself constantly fiddling with the thermostat or using
space heaters in some areas?
Found that the guest bedroom is too cold for your visiting mother
in law?