My drain hose outside is frozen, what should I do?
By-pass the water softener (refer to owner manual or contact your installer). Wait for the drain hose to thaw or alternately apply hot water (not boiling) to the drain hose outside.
My water softener is in an outside box.
Consider by-passing the water softener until milder weather returns.
My water softener is outside / in a garage / out building. What can I do to prevent the inlet / outlet hoses from freezing?
Insure you have adequately insulated all pipe work within the outside box / garage / out buildings.