I have a condo and for the last year off and on I get a banging sound in my pipes. The pipes bang for about 5 seconds, go away, then come back. This pattern can continue for a few hours. The noise can disappear for weeks then come back. Funny thing is there is no water in my unit running when the noise occurs. None of my toilets leak. Could this noise be coming from the unit below me or next to me?? Other people in the building hear the noise as well. Could it be air in the lines, pressure regulator or bad toilet??
thanks
Pete