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Read through the material below, then test your understanding.
Module Lessons
Hot Water
Hot Water Legislation and Standards
System Selection Factors
Open Vented Hot Water Systems
Hot Water Storage Cylinders
Combination and Quick Recovery Cylinders
Unvented Hot Water Systems
Localised Hot Water Systems
Hot Water Safety Controls
Discharge Pipework (D1/D2)
Decommissioning Hot Water Systems
Thermostatic Mixing Valves (TMVs)
Installing Shower Mixing Valves
Replacing Hot Water Components
Expansion of Hot Water Pipework
Testing and Inspecting Hot Water Systems
Hot Water System Fault Finding
Maintenance and Component Replacement
Lesson Overview
Open vented hot water systems use a cold water storage cistern and an open safety vent pipe to deliver domestic hot water safely at atmospheric pressure.
Learning Objectives
Explain the operating principles and pipework layout of open vented hot water systems.
Distinguish between direct, double-feed indirect, and single-feed indirect system designs.
Identify the correct sizing, positioning, and safety rules for cold feed, draw-off, and vent pipework.
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