Our Wiring Diagrams section details a selection of key wiring diagrams focused around typical Sundial S and Y Plans.

FAQ V4073A Mid-position (Y Plan) Valve Operation - How a Mid-Position valve operates within a Sundial Y Plan Heating System

FAQ W Plan Hot Water Priority System - How a W Plan Heating system operates

FAQ Pump Overrun Wiring Diagrams for Y Plan incorporating a ST9400 Programmer

FAQ Pump Overrun Wiring Diagrams for S Plan incorporating a ST9400 Programmer

FAQ Pump Overrun Wiring Diagrams for S Plan Plus incorporating separate diagrams with ST9100 Time Switch and ST9400 Programmer

FAQ T4360B Frost Protection Kit - Details how to operate a Frost Protection Kit

FAQ T6360 Room Thermostat Wiring & Operation

FAQ Wiring Diagram S Plan Pump Overrun (ST9400 and DT92E)

FAQ Wiring Diagram S Plan Plus Pump Overrun (ST9400 and DT92E)

FAQ Wiring Diagram Y Plan Pump Overrun (ST9400 and DT92E)

FAQ Wiring Diagram Y Plan Pump Overrun (ST9420 and DT92E)

FAQ Wiring Diagram S Plan Pump Overrun (ST9420 and DT92E)

FAQ Wiring Diagram S Plan Plus Pump Overrun (ST9420 and DT92E)

FAQ Wiring Diagram Combination Boiler (ST9120)

Honeywell T4 Additional Wiring Diagrams

LYRIC T6 Additional Wiring Diagrams

V4043 Zone Valve S Plan Operation

Heating Controls Wiring Guide Issue 17