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Heat cost allocator

Heat cost allocators are devices for the consumption-based calculation of heating costs, abbreviated to Thermomess with HKV - supplemented by V for evaporator or E for contemporary electronic devices. HKV are not measuring devices, but recording devices because - unlike, for example, a heat meter - no amount of heat is measured, but only non-specific units are recorded that reflect the summation of the temperature (difference) over time. Heat consumption can only be derived from factors that result from the type and size of the radiator. Ultimately, the individual heating costs of the individual users are determined by calculating the ratio of the recording results of several similar heat cost allocators in the heating cost billing.

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inexpensive recording devices

In most cases, heat cost allocators are probably the most cost-effective devices for determining the consumption of heating energy.

easy construction

Heat cost allocators can be mounted on almost all standard radiators, for example, by spot welding using special screw connections.

long-term proven measuring devices

Heat cost allocators have been around for many decades and have become more and more accurate and reliable over the years

Heat cost allocator based on the evaporation principle

Our Prismatic heat cost allocators are attached to the individual radiators. They record the proportional energy consumption of the individual radiators in relation to the entire building and work according to the evaporation principle. The measuring liquid evaporates in an ampoule due to the heat radiation of the heating element. The liquid level in the ampoule can be read on a scale. Prismatic heat cost allocators have a standard scale. As a result, the line units read must be multiplied by the power factor of the radiator in question. This product then gives the consumption units. In contrast to this, the older 080 devices are matched to the respective radiator with a product scale; the line units read correspond to the consumption units.

Evaporator-based heat cost allocators that were installed before July 1981 had to be replaced by the end of 2013 according to the heating cost ordinance, the Prismatic heat cost allocators are still permitted - at least until the end of 2026. From 2027, only electronic devices with radio interfaces are permitted!

Heat cost allocators based on the evaporation principle are still widespread. Although the accuracy of these devices is repeatedly doubted, it remains undisputed that these devices combine many positive properties when used in accordance with the standards:
According to a study by Stiftung Warentest, heat cost allocators based on the evaporation principle have an average error rate of only 4.725%.
Evaporators are inexpensive and also capture heat precisely in spring and autumn thanks to the back part made of die-cast aluminum with a high thermal conductivity function. They are tamper-proof, dimensionally stable even at the highest temperatures, and the amount of the extensively examined measuring liquid “methyl benzoate” is harmless to health.

Electronic heat cost allocators

Nowadays only electronic heat cost allocators are installed NEW. Here, the heat output of the radiator is recorded by a measuring sensor and shown numerically on an LCD display. The electronic heat cost allocators are designed for a technical operational life of ten years without changing the battery. The main advantages of these devices are that they can be used to record the exact date of consumption using a "memory value" and that they can be read off in the event of a change of user.
If the device is damaged, contamination by a measuring liquid is not possible and the readings do not have to be corrected in the event of a shortened period of use or an interim reading.

By the end of 2026, all heat cost allocators must be converted to wireless devices in accordance with an EED directive. Since the period of use of the devices is designed for 10 years, all devices delivered today are either all already radio - or at least ready for radio.

Radio systems

Modern radio technology saves entering apartments and offers many other advantages.


We create a consumption-based heating cost bill for your property or a complete house ancillary cost bill.


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