Can't shut off water at "Red water Valve"

[arthurio55]

Hey guys, having an issue here. I'm trying to shut off the cold water supply to the whole house via this water valve that is above the water heater but it seems to keep on turning clockwise and counterclockwise forever and not doing anything. Need some help on what may have caused that, thanks. I have attached a picture for reference.

 

[johnjh2o]

The valve needs to be replaced. It's a gate valve and there known to have the stems snap not allowing the gate to move up or down in the valve. When you do replace it use a ball valve.

 

[arthurio55]

So how can I shut off the water to the house to replace the red valve?

 

[johnjh2o]

If your on city water there should be a valve at the curb. If your in a cold climate it will be below ground inside a curb box that requires a key to turn it off. If your on a well just turn the pump off and drop the water pressure.