Ok, I've asked two of the local HVAC companies in the area I'm moving into and gotten two conflicting answers... So please be gentle with me.
I'm moving into a house in Michigan which has a natural gas fired baseboard hot water heating system.
It was built without much in the way of thought regarding energy conservation. To put it mildly.
There are separate piping loops for various sections, with levered shut-off valves on them. All are currently open.
Anyway, I asked the HVAC folk if I could, say, shut off the valves to the garage area and what this would do in regards to the circulating pump.
(There's enough heat leakage that I don't have to worry about the pipes freezing. At least until I do a lot more retro-insulating).
One said it would make the pump work harder and wear it out sooner; the other said it would be ok and might even save a bit of electrcity.
(In the long run I'll have them do proper zoning and controls, and get a new higher efficiency furnace, etc., etc., but all that's got to wait until I find out the truth behidn the Kennedy assasination.)
Seriously, for now I'm mostly concerned about the pump issue, and given that I got two different answers, I'm appealing to the experts.
Thanks