Heat transfer for building heating

Heat is produced by an individual boiler or a water/water or air/water heat pump (apartment or single-family home), or by a collective boiler system for apartment blocks, ERP or industrial buildings.

When the boiler room is collective, it can supply hot water to one or more buildings, or steam to an industrial building or a network that supplies buildings via substations. Direct steam supply is no longer used for residential or commercial buildings, partly because of the risk of scalding and the complexity of the piping system.

Heat is transmitted to the various rooms of an apartment, building, ERP or industrial building by circulating fluids that supply the heating elements (radiators, convectors, unit heaters, etc.).

The warm air produced by a generator is conveyed through ducts and supply and return outlets. The warm air is mixed with the ambient air and heats it.

When hot water is used inside buildings, it can be circulated by thermosyphon for older installations, or by pump, which provides greater flexibility for smaller-diameter pipes.

When the fluid is vaporized water vapour, it condenses, releasing its heat, and the water returns to the generator.

In anticipation of the widespread adoption of ecogestures in homes and business premises alike, decree no. 2023-444 of June 7, 2023 on temperature control systems for heating and cooling systems and the insulation of heat and cold distribution networks was published in the JO of June 8, 2023. In practical terms, it requires all homes to fit thermostats on their radiators from 1 ^er January 2027.