Ever wonder how a boiler heats different rooms to different temperatures? Zone valves. Those motorized units on each copper line open and close based on thermostat calls, directing hot water only where it's needed. Pretty clever system, actually. But here's what matters: they need annual maintenance to keep working reliably. Riley Plumbing & Heating serviced this Stateline home's multi-zone setup, checking valve operation, controller signals, and water pressure. Book your boiler maintenance before winter peaks. Prevents the kind of cold-room surprises nobody wants in January.