TRRTP021 - Pravilnik o načinu delitve in obračunu stroškov za toploto v stanovanjskih in drugih stavbah z več odjemalci

This standard describes a method to calculate the power and the storage volume required for the dimensioning of domestic hot water systems (DHW). The applicability ranges from direct water heaters (no storage volume and a comparatively large effective heating power) to long term storage systems (e.g. seasonal storage with a comparatively small heating power and large storage volume).
This standard is applicable to the following water storage systems
-   storage charging systems characterized by a minimised mixing zone, e.g. layer-charging storage tanks or storage tanks with external heat exchangers, and
-   hot water tanks and storage systems characterized by a distinct mixing zone, e.g. storage systems with internal heat exchangers,
and for different uses.
The scope of the second part is to standardise the methods for determining the energy need for domestic hot water. This standard covers the domestic hot water needs in buildings.
The calculation of the energy needs for domestic hot water applies to a dwelling, a building or a zone of a building.
This standard also provides energy needs for different application cases of DHW-systems in hourly, monthly, and seasonal time steps, based on national default values.

This European standard applies to heat cost allocators which are used to capture the proportionate thermal output of radiators in consumer units. If an account unit comprises consumer units of different types (e.g. technically different types of heating systems or differences due to the consumer behaviour, e.g. industrial plants as opposed to private apartments), it could be necessary to divide this account unit into groups of users. Heat cost allocators enable the determination of the heat consumption only of each radiator in a consumer unit as a share of the total heat consumption of the account unit or user group; it is therefore necessary to determine this total heat consumption either by measuring the consumed fuel quantity or the amount of heat delivered (the latter by means of a heat meter, for example). For the appropriate use of the heat cost allocators in accordance with this standard, the heating system needs to: correspond to the state of the art at the time of installation of the heat cost allocators; be operated in accordance with the state of the art. This standard specifies that heat cost allocators shall not be used for heating systems where the temperature of the heating system falls below or exceeds the temperature limits of the heat cost allocators, where the rating factor for the thermal output, KQ, cannot be clearly specified or where the heating surface is inaccessible. This applies usually to the following heating systems: floor heating; radiant ceiling heating; flap-controlled radiators; radiators with ventilators; fan-assisted air heaters; heating systems with steam-operated radiators.

Heat cost allocators in accordance with this standard are instruments for the registration of the heat output of radiators in consumer units. Consumer units are dwellings, office buildings, business premises, industrial plants in which the heat is supplied by a common central heating systems or by a common district heating connection. A complete grouping of consumer units is called an account unit.