There is an iron pipe in the toilet in my house, and a gate valve that can only be screwed up to 90

You twist it back and forth, and follow the judgment:

Fully open state screwed to full off state: there is no sound when screwing at the beginning, and there may be sound in the final stage when screwed all off state to full open state: there may be sound when screwing at the beginning, and there may be sound in the final stage, and there must be no sound after it is in place.

The effect of this valve depends on where there is no water in the pipes in your house after you turn it all off.

My personal judgment is the water supply valve of your water heater. Do you have a solar water heater or some other type of water heater in your home?

[There is an iron pipe in my toilet, and a gate valve that can only be screwed to 90 degrees is pressed on it, but I don't know if it is screwed to 0 degrees or off? Or is it off when screwed to 90 degrees? When I screw it less than 90 degrees, I can hear the water in the pipe, and if I screw it, the sound of the water will stop immediately.

Question: Is it screwed to 90 degrees in use or screwed to 0 degrees to use it? What does this valve do?

Twisting it clockwise to the end is to turn it off, and twisting it to the end counterclockwise to turn it on.

What does this valve do? It is not the main switch of the toilet.

Screw it up to 90 is off. The general design of pipeline valve is when the screw head of the valve is open parallel to the pipe, and the screw head and the pipe are closed at 90 degrees. The valve generally controls its own water pipe, and some control the water downstairs.

When the valve tail is perpendicular to the tube, it is closed.

When in the same direction as the officer, it is open.