Can I continue running my unit when it makes noise when it comes on, what would cause it to do that

When my air conditioner turns on inside my house, it makes a thumping noise. Sometimes you can faintly hear it continually until it kicks off. It may be worse one day and not so bad another. I need help please!

Hope some one can help. I have just had a new main pipe laid through my driveway due to a leak. Now when I turn on the cold tap on in the bathroom it makes a loud thumping noise, but not all the time and not always the 1st time I turn the tap on. This morning I turned it on and it was fine and then...

My home a/c unit will not kick on. When I drop the thermostat temp I hear a click on the outside unit and then it just makes a buzzing/humming noise. The start capacitor is the dual style but is not swollen at all. Its Sunday and no stores are open so it barrowed my neighbors capacitor (same size)...

I am a builder. I have a homeowner who has 3 Trane A/C units. It took a while to distinguish which unit was squeeling. But we now know that when the second floor unit comes on the A/C compressor on the outside make a loud squeeling noice that wakes the homeowner at night. It makes the noise for...