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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
Localised water heaters provide point-of-use hot water to individual outlets, eliminating long pipe runs and dead legs. They operate as either instantaneous or small-capacity storage units.
Learning Objectives
Distinguish between localised instantaneous and storage (displacement) water heaters.
Identify the operating principles, expansion arrangements, and normal dripping behaviour of open-vented point-of-use heaters.
Apply statutory regulations and temperature safety limits for installations under 15 litres.
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