The water softener should be hooked up to both hot and cold throughout the house--including the cold water in the kitchen faucet.
Drinking Soft Water Is Not Bad for Health
Salt in the water softener tank does not dissolve and magically make the water "soft." Soft water is actually water with the minerals and heavy metals taken out of it. The function of the salt is to create a salty brine that cleans the ionic-charged resin that pulls the minerals out of the