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Upgrade now2-Port Valve Systems: S-Plan & S-Plan Plus
Read through the material below, then test your understanding.
Module Lessons
Central Heating: Design & Controls
Building Regulations Part L & Boiler Interlock
Sealed Heating System Layouts
2-Port Valve Systems: S-Plan & S-Plan Plus
3-Port Valve Systems: Y-Plan & W-Plan
System & Combination Boilers
Multiple Boilers & Low Loss Headers
Heating Controls & Components
Advanced Heating Controls
Selecting Systems & Controls for Dwellings
Underfloor Heating: Design & Layout
Underfloor Heating: Pipework & Commissioning
Selecting Heating System & Component Types
Design Information Sources
Heat Loss & Heat Gain Principles
Calculating Room Heating Requirements
Sizing Heating Pipework & Circulating Pumps
Selecting Central Heating Boilers
Sizing Expansion Vessels & F&E Cisterns
Calculating Central Heating Component Sizes
Positioning Heating System Components
Wiring Combi & Gravity Hot Water (C-Plan)
Wiring 3-Port Valve Systems
Wiring 2-Port Valve Systems
Wiring Advanced Controls & Frost Protection
Safe Isolation & Electrical Testing
Commissioning Standards & Regulations
Planning & Preparing the Commissioning Test
Flushing & Hydraulic Testing
Water Treatment: Cleansers, Neutralisers & Inhibitors
Power Flushing
System Balancing
Compliance Certificates & Notification of Work
Central Heating Component Anatomy
Gathering Fault Information
Using Manufacturer Instructions for Diagnosis
Methods of Repairing Central Heating Faults
Safe Isolation During Maintenance & Repair
Diagnostic Testing Procedures for Faults
Alternative Wiring Arrangements
Lesson Overview
S-Plan and S-Plan Plus systems use independent two-port motorised valves to control heating and hot water circuits separately. In dwellings exceeding 150 m², an S-Plan Plus layout provides mandatory multi-zone time and temperature control.
Learning Objectives
Explain the hydraulic layout and operating principles of S-Plan and S-Plan Plus systems.
Identify the correct sizing criteria for two-port motorised zone valves based on boiler output.
State the regulatory zoning requirements and the role of an automatic bypass valve.
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