Q: When I relocated to another state, the agent who sold me the home suggested I have a water softener installed. I purchased a water softener and had it installed by a plumber. Now that I'm selling the home, the inspector noted that the water softener has a cross-connection.

The buyers want it repaired. What is a cross connection, and if the softener is supposed to have one, should the plumber or the agent be responsible for it?