Central Heating revision notes
System layouts, controls and interlock, emitters and balancing for domestic heating.
- 9notes, free to read
- 103questions, free to try
- 3topics
C&G Unit 206: Central Heating Layouts & Radiators
Choosing radiators from a room heat loss (worked example)
Turning a room heat-loss figure into the number of radiators needed, and why output ratings must be corrected.
How a wet central heating system works
The heat source, circulation, emitters and flow/return loop that make up a typical domestic wet system.
One-pipe and two-pipe heating layouts
How one-pipe and two-pipe central heating circuits differ and why two-pipe is the usual modern choice.
Sizing a sealed heating expansion vessel (worked example)
Turning a system water content into an expansion volume and then a vessel size, with the steps shown.
Unit 206: Central heating layout systems
One-pipe, two-pipe, and fully pumped S-plan and Y-plan arrangements.
C&G Unit 206: Heating Controls, Interlock & Balancing
Balancing radiators with the lockshield valves
Why a heating system is balanced and an ordered way to set the lockshield valves for even heat.
Heating controls and boiler interlock
What each common heating control does and why interlock stops the boiler firing when no heat is needed.
S-plan vs Y-plan: how the valves control the system
A visual walk-through of why S-plan and Y-plan differ only in valve control.
C&G Unit 206: Heating Water Treatment & Cleansing
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