On Mar 6, 8:54*am, Noel wrote:
I have steam heat in a 1 family house with 2 levels and an unheated
basement. I set the thermostat at 74 ( its an old house with recent
new windows ). Lately, the temp outside has been on the mild side, and
I have a very sunny south exposure which warms up the facing room
pretty much when the sun comes out. When this happens, I have the
tendency to lower the temp to 69-70 for about 5 hours. Of course, by
the end of those 5 hours, the sun is gone and the room is getting
cooler. I reset the thermostat back up to 74. Now, someone told me I
am causing the boiler to *work harder to bring it up back to 74, so I
am not saving much gas that way. He said to leave it at 74 , even when
the sun enters. Do I save money that latter way?

No, the boiler is not working harder. You are doing the equivelant of
what a programmable thermostat does, lowers the temp when it's not
needed, and raising it when it is needed. Your only talking a matter
of 4 degrees. If you heating system is working good, it should warm up
the area in about half hour tops. The advantages of saving fuel cost
and your boiler being off for a long period during the day far
outweigh the disadvantage of having the boiler stay on longer to meet
the desired temp in your house.