My friend has a problem getting blasted by hot or cold water when he is taking a shower and someone turns on the water elsewhere in his house. Curb pressure is about 100 PSI and regulator takes it down to
50 PSI. He has tried a new regulator. The distribution manifold is not near the regulator or water heater which is in the garage, rather it is near the middle of the house fed with 1/2 pipe. He doesn't want to add temperature compensating shower controls. I suggested that separate regulators for the hot and cold water supply might help. I am also trying to get him to install a permanent pressure gauge on the curb side, as I would like to see if the input side has been restricted somehow.Jimmie