I noticed this morning that the temperature on my 2nd floor (1 of 3 zones in my house) was at 70 degrees F. I had it set with my thermostat at 65. I turned it down to 60, and it still stayed at 70. I disconnected the thermostat, completely exposing the two wires and separating them. The other two zones are working fine, one is set at 65 and is staying there, the other is set at 60 (rarely used part of house), and it is staying at 60. Is there some internal thermostat on my oil burning unit that I need to adjust, or is it time to call in the pros?

Thanks,
Jim

You should have three solenoid valves on a hot water manifold. Each valve is controlled by a stat. If you short those two wires together the valve should open and allow water to circulate. If the wires are open the valve should be closed with no circulation. The valve is probably bad.

OK, thanks. Since that is beyond my technical capabilities, I will get with my furnace guy.

Is this a boiler or forced air?

I have an oil burner with hot water baseboard.

Are the radiators upstairs warm even after thermostat has been off for a long time?

Yes, the radiators have stayed warm for the past day or so, long after I disconnected the thermostat.

OK you probably have a bad zone valve. They are rather costly, but it's not a job you probably want to tackle.

Thanks, I have a call in to my furnace guy...