yes.
Take 2-3ml oxalic acid and pour it into an empty thermos. Tilt the thermos slightly and shake it, and you will hear a sneering sound inside. It means that the scale is dissolving. Look through the bottle mouth to see where there is scale, and then transfer the oxalic acid solution there until it is completely dissolved. Be careful not to splash it in your eyes. Pour out the decomposition solution and wash it twice with clear water.
Extended information:
Precautions for the use of thermos:
1. The water injected into thermos should not exceed the maximum water level line, nor should it be too little, because overflow or empty burning can easily cause the kettle to malfunction.
2. To fill the thermos bottle with water, first connect the power cord with the kettle body, and then the user plugs the other end into the power socket to heat it. For an electric kettle with a switch or an automatic electric kettle, pull off the switch and connect the kettle to the power supply.
3. The electric kettle is a high-power electrical appliance. Read the instruction carefully before using the electric kettle, and choose a proper power socket. The socket should be used independently and should not be used together with other high-power electrical appliances.
4. The power plug should be kept dry and clean. Never shower it with water or place it near the fire source to avoid leakage or burning.
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