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Upgrade nowEffective Height & Flue Routing
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
This lesson covers the calculation of effective flue height, permissible routing, and component resistance factors for open-flued domestic gas appliances under BS 5440-1.
Learning Objectives
Explain the distinction between actual vertical height and effective flue height.
Calculate effective flue height using appliance inlet, outlet, and component resistance factors.
Apply British Standard design rules regarding primary flue length, offsets, and maximum external runs.
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