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Upgrade nowOpen Flues & Flexible Liners
Read through the material below, then test your understanding.
Module Lessons
Domestic Fuel Systems, Combustion & Flues
Fuel Properties: Gas, LPG & Solid Fuel
Fuel Properties: Oil & Low-Carbon Alternatives
Storing Oil, Coal & LPG
Storing Biomass & General Fuel Storage
Fuel Delivery & Distribution
Complete & Incomplete Combustion
Carbon Monoxide Poisoning
Combustion & Ventilation Air Requirements
Ventilation Categories & Calculations
Ventilation for Open-Flued & Room-Sealed Appliances
Flueless Appliance Ventilation Calculations
Types of Chimney & Flue Systems
Open Flues & Flexible Liners
Flue Terminals & Builder's Openings
Terminal Guards, Flue Blocks & Ridge Terminals
Room-Sealed (Balanced) Flues
Effective Height & Flue Routing
Flue Temperature, Condensation & Termination
Class 1 & Class 2 Flue Construction
Rigid & Flexible Metallic Flue Systems
Flue Testing Procedures
Flue Gas Analysis
Lesson Overview
Open-flued appliances draw combustion air from the room and rely on natural or fan-assisted draught to evacuate products of combustion. Flexible metallic liners safely reline existing masonry chimneys to prevent condensation and leakage.
Learning Objectives
Identify the operating principles and key components of open-flue systems.
Distinguish between single-skin and double-skin flexible metallic flue liners and their fuel applications.
State the installation, sealing, and testing requirements for open flues and flexible liners in line with BS 5440-1.
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