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Read through the material below, then test your understanding.
Module Lessons
Cold Water
Incoming Mains: Communication vs. Supply Pipes
Installation Depths and Building Entry
Direct Cold Water Systems
Indirect Cold Water Systems
Siting and Installing Storage Cisterns
Float-Operated Valves and Overflows
Principles of Backflow
Terminal Fittings and Taps
Non-Mechanical Backflow Prevention (Air Gaps)
Water Treatment and Distribution
Mechanical Backflow Prevention Valves
Commissioning: Testing and Flushing
Lesson Overview
Float-operated valves regulate the water level in cold water cisterns, whilst warning and overflow pipes prevent property damage from uncontrolled flooding. Understanding their working principles, orifice selection, and installation dimensions is essential for regulatory compliance.
Learning Objectives
Identify the operating principles and applications of the four main types of float-operated valves.
Select the correct valve orifice based on incoming supply pressure and diagnose common valve faults.
Apply the regulatory positioning, sizing, and screening requirements for warning and overflow pipes.
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