thank you max for reply: "When it sticks cutting the power will not work, it sticks, you must disconnect it permanantly or fix it." the only thing here is if what you say is true then disconnecting it would be useless too, but it's not, when it locks up i unplug it and it unlocks. so if it sticks regardless then even unplugging it would leave it stuck according to what you say, but it's not. if i can interrupt the power then it will serve the same as "disconnected" so long as the switch is off... this is what i'm trying to achieve, but i have no way of knowing which wire powers the valve.