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Read through the material below, then test your understanding.
Module Lessons
Central Heating
Introduction to Central Heating & Part L
Heat Emitters: Radiators and Convectors
Radiator Valves: TRVs and Lockshields
System Layouts: One-Pipe and Two-Pipe
System Layouts: Microbore and Manifold
Boiler Types: Regular, System, and Combination
Condensing Boiler Principles
Open Vented Central Heating Systems
Sealed Central Heating Systems
Expansion Vessels and Pressure Relief
Central Heating Pumps and Circulators
System Controls: Programmers and Thermostats
Motorised Valves: 2-Port and 3-Port
Fully Pumped Systems: The Y-Plan
Fully Pumped Systems: The S-Plan
Filling, Venting, and System Balancing
Water Treatment and System Protection
Lesson Overview
Water treatment and corrosion prevention are vital to maintain heating efficiency, protect boilers, and prevent system component failure. This lesson covers corrosion causes, sludge formation, flushing techniques, chemical inhibitors, and mechanical filtration.
Learning Objectives
Identify the causes and symptoms of corrosion, sludge, and limescale in wet central heating systems.
Explain the methods used to protect heating systems, including chemical inhibitors, magnetic filters, and power flushing.
State the correct procedures for safe chemical application, testing, and environmental disposal of heating system water.
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