Go look at the back of the 40278. The bypass handle should be pointing towards the unit (Service position). If it points away (Bypass), you are using raw hard water.
Rust turns resin beads into slimy, dark green mush. Buy a liquid resin cleaner from Home Depot. Pour it into the brine well. Force a manual regeneration. Frequently Asked Questions (FAQ) Q: Does the 40278 remove chlorine or lead? A: No. This is a water softener, not a filter. For chlorine taste or lead, you need a reverse osmosis (RO) system under the sink, or a whole home carbon filter before the 40278. 40278 water softener
A: Yes. If you are on a low-sodium diet, potassium chloride works in the 40278. However, it is 3x more expensive and can cause "mushing" in the brine tank. Clean the tank yearly if you use potassium. Go look at the back of the 40278