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Upgrade nowFlushing & Hydraulic Testing
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
Correct hydraulic pressure testing and multi-stage flushing ensure central heating installations are structurally sound, leak-free, and cleared of damaging installation debris before final chemical treatment and handover.
Learning Objectives
Identify the statutory and British Standard parameters for testing metallic and plastic heating pipework.
Explain the correct preparation, isolation, and safety procedures required before applying test pressure.
Distinguish between cold and hot flushing procedures and their roles in preventing component damage.
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