Im confused weather I need a normally open or normally closed zone valve. With thermostat off the lever is loose, leaving me believe the zone valve is open. So would i need to put in a normally closed
Most that I've seen (not a lot!) use the motor to open the valve and rely on the spring to push it back closed when power is removed. SO, those I'm familiar with are normally closed. Using the manual open lever is pushing against the spring, so would likely get tighter as you open the valve.