i have a problem with water pipes. when i first bought the house i had no problems at all. last year i had a grass planted in my backyard and a sprinkler system installed. after the first couple of uses everything was okay, but after a few weeks the pipes started banging. when the toilet was flushed, a faucet was cloesd and the washer was used. i tried instaling water arrestors in the ones that had the loudest noise, did not work. this winter when i went to shut of the sprinkler for the winter, the banging went away. i asume that the sprinklers are letting air into the water system. do you have any advise that may help me, thanks very much.