Technical Booklet F1 Conservation of Fuel and Power in Dwellings·Page 9
Definitions: Pipes, ducts and vessels
Pipes, ducts and vessels are components of space heating or space cooling systems that carry heated or chilled liquid or gas, including associated fittings.
"Pipes, ducts and vessels" means any pipe, any duct and any vessel in a space heating or space cooling system that is intended to carry a heated or chilled liquid or gas and includes any associated fittings;
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