Whenever we turn on water or flush a toilet we hear a humming noise. What could this be?
Thank you.

Humming is caused by vibration. The first place I would check is the level in the toilet tank. It should be 1/2" under the white overflow tube. If it wasn't ballcock hum then I would attempt to track it down by feel or sound. Let me know what you find. Good luck, Tom

When we flush our guest bath toilet, as it starts to fill we hear a rattleing noise in the pipes. I have been told it is air in the lines. It only happens when we flush this bathroom. I have checked the tank level, it is good, the insides are a little old and could use replaceing. But other than this what can I look for or do to get the air out of the lines? BTW the noise sounds like it comes from the kitchen when we flush? Just sounds that way, it could just be noise transfer.

Do you see bubbles when you fill the tank telling you the line's full of air?Poor ole air! Gets blamed for,water hammer, lack of pressure, nosey pipes and all kinds of stuff. If you did have air in your pipes,(which I don'[t think you have), all you would have to do would be to turn on the topmost faucet and the air would raise to the top aqnd bleed rightout. And w2hile we're on the subject air lock only happens if the pressure's shut off and you're trying to drain the system and the rest of the faucets are closed setting up a vacuum called "air lock". Could be a loose pipe strap on a cold water branch that's not tight and what you hear is the pipe rattling against the stud as the water rushes thriugh. In any event it's vibration and you track vibration down by sound and feel. Good luck, Tom