We were absent from our home for 4 months. When we returned, we notice the kitchen faucet 'hammers' when the hot water is on full, creating an effect like a massage shower head. This usually occurs when we use the kitchen faucet hot water on full, but recently woke us in the middle of the night when the outdoor sprinkler system came on, and the refrigerator water line began hammering. The house is 13 years old, the hot water heater was replaced 7 months ago, but this problem only started when we returned from our long absence.
I have read about 'air hammering' in pipes, but this isnt exactly that...it's this staccato high frequency high pressure water massage in the kitchen.
anyone got any clues?