I have recently put in a water softener in my home for the first
time. The softener came with a GE #760 control valve on it. When it
is regenerating there is a loud water hammer between cycles C4 & C5.
I also have an iron filter ahead of the softener. I have tried a 3/4"
hammer arrester before and after the softener with no luck. I also
ran a regeneration with the iron filter in bypass. The hammering
continued. I am on a well and other then the hammering the softener
works fine. Any ideas.