: Sometimes I hear this humming/vibrating sound in my house, even when there is no water being used. The sound is similar to a fog horn and continues for a few seconds and then goes away. When I touched the valve for the main water line coming into the house, it seemed to be vibrating. The sound comes and goes 1-2 times during the night and day. Do I need to call the plumber to check it out or further investigate where the noise is coming from. Do you think if I don't take action it could turn out to be something dangerous.

Sean,
Check the link below for good info on humming. Terry

• Mysterious answers concerning humming sounds in house, (click here)