Honeywell Sundial Plan Wiring Centre The Wiring Centre has been designed to simplify the wiring of Sundial Plan central heating installations. This provides a clearly marked terminal block for each component in the system with each wire having its own terminal. Key Features and Benefits: Dedicated Terminal Block for Each System Component One Wire per Terminal Connection No Wiring Diagram or Additional Instructions Required On The Board Fuse - Plus Spare Strong, Fire Retardant PC ABS Box Height: 94mm Width: 116mm Depth: 126mm Manufacturers 1 Year Guarantee