Heat cost allocators are devices attached to individual radiators in buildings that measure the total heat output of the individual radiator.
Heat cost allocators can be either electronic, where one or two electronic thermosensors[1] and a microcontroller are used to calculate the heat consumption of radiator by the temperature difference between the radiator and the air in room,[2][3] or evaporative, where a special, calibrated liquid in a capillary tube records the total heat absorbed from the air (for which an average allowance is made) in addition to that output by the radiator.
[4] Tubes filled with methyl benzoate according to DIN EN 835 can be used by checking the color change.
With electronic heat cost allocators, the scaling is achieved through programming.
The evaluation factor is determined when the heat cost allocator is installed.