A radiator meter accurately records the heat output per radiator. The measurement system is a so-called ratio system. The meter readings indicate how much heat the residents have consumed in relation to each other and the total. This allows the total energy costs of the entire housing complex to be paid fairly by all residents.
Determining the heating costs
All meter readings (units) of all homes in a residential complex are added together. Of the total fuel costs, the majority are generally settled as variable costs. The share of these costs is thus related to the individual consumption of the residents. The remaining part of the total fuel costs is called the fixed costs; these are usually divided by floor space. The variable costs are divided by the total number of registered consumption units of the entire housing complex. This creates a price per unit. This price is multiplied by the total number of units per dwelling. This creates the consumption-based share of heating costs per resident.
Heat output when heating is not on
Radiometers can, under certain circumstances, also register heat emission when the heating is not on. This phenomenon can occur with:
The radiator is heated by solar heat and takes on a temperature that is higher than or equal to the ambient temperature. If, for example, a window is opened in this situation, the ambient air cools faster than the radiator.
Hot tap water rises in the vertical return pipe, heating the radiator. The radiator pipe transfers heat to the radiator that is turned off, causing it to heat up.
In these situations, the radiator temperature will be higher than the ambient temperature. This is particularly common with small radiators.
An electronic radiator meter recognizes the difference in radiator and ambient temperature and, according to the standard applicable to this meter, will start counting. This is a matter of a few units, because in both situations the radiator emits only small amounts of heat. However, the radiator meter does not recognize the cause of the temperature difference. This fact is also taken into account in the standard.
The heating bill remains correct because:
This phenomenon occurs in the entire building, so the consumption ratios between them remain the same. In the entire housing complex, a number of units more are registered as a result. As there is no additional fuel consumption, the price per unit will drop. The consequence per resident in the settlement will therefore be zero.
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