How to test zone valves

[hydro-newbie]

Hi all, I live in a home with 2 heating zones (hot water heat), and often the area where I live is getting hotter than the temperature I have my thermostat set at (often 6 degrees warmer). I am thinking maybe my zone valve is stuck open (the one on the left).

So I just tried to do a simple test with the valves by operating them manually. I got the following results.

With boiler power on:
Left valve operates very easy and stays in manual position.
Right valve operates very hard and then spins back to auto position.

With boiler power off:
Both valves spin hard to get to the manual side and the spin back to auto.

Does this tell me anything? I did not expect the valves to move back to the auto position by themselves. Do I need to do a voltage test first before I can assume anything? Thank you.

 

[hydro-newbie]

Well I am going to answer myself. If the valve has power and you try to move the lever away from the "auto" side, it should be difficult to move and it will immediately wind back. This only applies to when the thermostat is off. If the valve does not wind back then the actuator is shot.