In a y plan heating system you must have a wire connecting the hot water off terminal at the programmer usually terminal number 1 and the satisfied terminal on the cylinder thermostat. The cylinder is a purpose designed unvented water heater.
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Unvented cylinder y plan wiring diagram. Output from the normal cylinder thermostat is connected to the high limit thermostat and the output from that powers the 2 port valve motor. Wiring is based on the standard y plan with the addition of a high limit thermostat and a 2 port motorised valve. Unfortunately the installer has not been able to work out how to wire it. X range x plan wiring diagram unvented cylinder option gyellow cut off dhw sl coil. Here coloured wires indicate the permanent mains supply to the boiler and programmer. The problem is that telford only show a wiring diagram for an s plan in the installation manual.
The problem is due to the combined cylinder stat and overheat stat. These terminals are joined together with the grey wire from the motorised valve. Orange grey wires from ch zone are not required please isolate opentherm make safe. This diagram shows the wiring layout using the most typical components. Heating control ntc cylinder sensor connect timer to the no dhw demand nc no dhw e orange grey 2. Wiring diagrams and further information continues below.
This video covers the wiring and electrical operation of a y plan system. The unit has a stainless steel inner vessel which ensures an excellent standard of corrosion resistance. These are shown at the bottom right of the diagram. Though they do say that a y plan can be used with the safety zone valve. All products are insulated. The outer casing is a combination of resilient thermoplastic mouldings and plastic coated corrosion proofed steel sheet.
Gallery of Unvented Cylinder Y Plan Wiring Diagram
