What kind of water should be added when the car radiator runs out of water?

[Jensen]

Automobile radiators should be filled with coolant, and the relevant explanations are as follows: 1. Composition of coolant: The main components of coolant are water, antifreeze, rust inhibitor, and foam inhibitor. 2. Additional notes: Antifreeze is used to prevent the car coolant from freezing and expanding, which could cause the engine cooling water passages to rupture. Different regions have varying requirements for the antifreeze properties of the coolant due to differences in temperature. Rust inhibitor is used to prevent the formation of rust. Foam inhibitor suppresses the formation of foam under the water pump impeller, as excessive foam can reduce the cooling efficiency of the coolant. Coolant cannot be replaced with water. In special circumstances where water must be added for replenishment, soft water should be used, as hard water can cause scale buildup.