The living room has an air conditioning socket vertical air conditioner is dedicated, and there is

Is your socket a single one? A single item of 220V--240V is normal, which belongs to high voltage. Do you see if the grounding situation is normal? If the grounding wire is normal, it will be fine, and you can use it with confidence.

Cabinet air conditioners, for safety, are used with air switches, because the cabinet current is large, the socket is powered on for a long time, the current is large, the insert is easy to age, and the fire is more likely to catch fire, so it is better to change the air switch to stabilize

Normally, this situation is due to the internal resistance on the socket that causes a voltage drop of 13V.

If you want to eliminate it, you need to remove the socket and connect it directly to the wall wire or socket, anyway, you have to reduce the length of the wire and the looseness of the connection.

Normal. It is possible that the air conditioner is grounded and induces voltage.