Shutting Off Water Supply to Leaking Radiator: Impact on Other Radiators?

Hello,
Yesterday, my neighbor downstairs made me realize that my radiator is leaking ... What not to flood her and wait for a professional, I wanted to turn off the water drain, but I do not know what to do and what to shoot ...

Here is something like this:


And what and how should I turn off so that no water flows to the radiator and maybe it doesn't run away? (Does this look like a screwdriver?)

And immediately the question:
1. If one radiator is disconnected from the circuit, will the water pressure in the others not increase and the others will start to leak?

These screwdriver notches serve to close the flow. set to 9-3 you will then cut off the power and return to that radiator. The water pressure will not increase if the temperature does not rise above the specified parameter.

How does your neighbor know that this radiator is leaking? Or maybe some pipe in the floor?

but you are sure whether it is leaking from the radiator or maybe from the flare. for tightening, these screws are used on a flat screwdriver, turn it and see if it stops and the pressure does not increase in the other

pablowp1 my neighbor knows because she has a stain on the ceiling ... and this heater was behind the wardrobe and I didn't look into it, it turned out that something was dripping from it, but it looked harmless. For the night I wrapped the valve or whatever it is with a towel and in the morning it was all wet ...: /

Determine whether it is leaking from the heater or from the tube / valve connection. If the valve does not work, turning it off anyway. By the way, why do you need a heater behind the wardrobe? do you choose your wardrobe?

The sea also drips from the connector - pipe, and the connector of the jumpers - radiator with a 30-32 mm key.

Sea or maybe?
mod - mirrzo