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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
Sizing domestic hot water pipework ensures required flow rates and temperatures are delivered at outlets without excessive velocity, noise, pressure drop, or water wastage.
Learning Objectives
Determine design flow rates, loading units, and permissible water velocities according to BS EN 806-3.
Calculate pipe diameters and frictional resistance using tabular methods and Thomas Box's formula.
Apply Water Supply Regulations limits for maximum dead leg lengths and draw-off waiting times.
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