The CSV1A is easy to clean. Just unscrew the red top. Remove the spring, bolt washer on top of the spring, and the little brass washer on the diaphragm. Then you can just pull up on the 10mm bolt head and the entire gut pack will come out. You can clean it with CLR, acid, or chlorine. Just don't let it soak.
When replacing everything just make sure the brass washer on top of the diaphragm has the sharp edge facing up, so it doesn't cut a slice out of the diaphragm.