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Upgrade nowDiagnosing Hot Water System Faults
Read through the material below, then test your understanding.
Module Lessons
Hot Water Systems: Planning & Design
Fuels Used in Hot Water Systems
Open Vented Storage Systems
Unvented Storage Systems
Localised Water Heaters
Unvented System Pressures
Secondary Circulation Systems
Hot Water Safety Controls
Functional Controls: Strainers & PRVs
Expansion Devices & Check Valves
Pressure Relief, Tundish & Composite Valves
Discharge Pipework: Sizing & Termination
Design Information Sources
Sizing Cisterns & Storage Vessels
Hot Water Pipework Sizing
Sizing Circulation & Boosting Pumps
Sizing Expansion Vessels & Presenting Designs
Installing Unvented Hot Water Systems
Testing & Commissioning Hot Water Systems
Diagnosing Hot Water System Faults
Component Fault-Finding: Pumps, Vessels & Thermostats
Servicing & Maintaining Hot Water Systems
Lesson Overview
Effective fault diagnosis on domestic hot water systems relies on structured customer consultation, interpreting system symptoms, and applying manufacturer instructions to locate hydraulic, thermal, and mechanical defects.
Learning Objectives
Identify the primary information required from end users to diagnose hot water faults.
Diagnose typical system faults and discharge causes in unvented hot water systems.
Recognise common fault symptoms, causes, and corrective actions in open vented storage systems.
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