Cabinet of Ministers Regulations No. 667 in Riga august 22, 2006 (pr. No 43) provisions on metrological requirements heat meters are Issued in accordance with the law "on a uniformity of measurements" the second subparagraph of article 6 and the law "on conformity assessment" 7. the first paragraph of article 1. determine the metrological requirements and the conformity assessment procedures for which heat meter is designed for heat accounting for residential and municipal buildings, as well as commercial and light industrial use, before the heat meter is placed in the internal market as well as placed in service. 2. the meaning of these provisions: 2.1 heat meter is a measuring instrument for thermal heat supply system for recording, in which the heat distribution to heat transfer fluid;
2.2. the heat meter is a compact measuring instrument or a combined measuring tool that consists of the flow sensor, temperature sensor pair, and Calculator, which functions independently and is included in the measurement;
2.3. symbols used are the following: definition of the term coolant temperature θ θ value θin heat exchange system in the entrance to the value θ θou heat exchange systems output ∆ θ temperature difference (θin-θou), if θmax θ θ > 0 ∆ upper limit value at which the meter is working properly maximum permissible errors (MPES) lower threshold, θmin θ at which the meter is working properly ∆ ∆ θ MPEs θmax upper limit value at which the meter is working properly ∆ ∆ θ MPEs θmin lower threshold at which the meter is working properly MPEs q coolant flow is higher in the short term, the qs permissible q value at which the meter is working properly the highest q value qp to permanent operation below permissible value q q, to which the meter is working properly heat exchange capacity P Ps P values in the upper limit at which the meter is working properly 3. The essential requirements for the heat meter to determine regulatory provisions on metrological requirements measuring instruments. The specific requirements for the heat meter to determine the provisions of this annex. 4. Heat meter meets the requirements of these rules and regulatory provisions on metrological requirements measuring instruments. 5. Persons who provide heat services, ensure that the heat meter is installed in accordance with the requirements established by these regulations and a measure of metrological requirements measuring means and heat meter provides accurate intended or foreseeable consumption measurements. 6. The manufacturer may choose conformity assessment procedures of modules B + F or B + D or H1. Module specific regulatory provisions on metrological requirements measuring instruments. 7. Heat meter for which type-approval was issued to this provision to the date of entry into force of the market and allowed to put heat meter, which made first-time verification, allowed to pass until they use the type approval expiration date, but if it is not set, the-by 2016 of 30 October. 8. The entry into force of the provisions by 30 October 2006. Informative reference to European Union Directive provisions included in the law arising from the European Parliament and of the Council of 31 March 2004, Directive 2004/22/EC on measuring instruments. Prime Minister a. Halloween economic Minister a. Štokenberg annex a Cabinet of 22 august 2006 Regulation No. 667 of specific metrological requirements

1. operating conditions specified by the manufacturer. The conditions are the following: 1. coolant temperature θmax, θmin ∆ and ∆ and θmax, θmin respecting restrictions ∆/∆ θmax, θmin = ∆ θmin > 10 3 k or 5 k, or 10 k; 1.2. the coolant pressure: maximum pressure (manometric pressure) that heat meter long passes, running a temperature corresponding to the upper limit of; 1.3. coolant flow: qs, qp, qi, where qp and qi ratio is defined as qp/qi > 10; 1.4. the heat capacity Ps. 2. Heat meters (meters) is down 1, 2, and 3. accuracy class. 3. The maximum permissible relative error of heat meter (for each class of accuracy) is expressed as a percentage of the true value: 3.1.  class 1: E = Ef + Et + Ec, with Ef, Et, and Ecu in accordance with this annex 10, 11 and 12; 3.2. class 2: E = Ef + Et + Ec, with Ef, Et, and Ecu in accordance with this annex 10, 11 and 12; 3.3. class 3: E = Ef + Et + Ec, with Ef, Et, and Ecu in accordance with this annex 10, 11 and 12. 4. Heat meter activity is persistent to static magnetic fields and energy source of power frequency electromagnetic field effects. 5. Electromagnetic field induced interference effects are permitted at such a level as to changes in the measurement of results is not greater than the critical change value according to this annex, paragraph 6, or to measurement readings can be considered a valid result. 6. the critical change value is equal to the heat meter with this heat meter applied to the absolute value of the MPE (3. of this annex). 7. The survival test (taking into account the period of time specified by the manufacturer) the meter meets the following criteria: 7.1. flow sensor measurement result after the durability test of the changes, compared with the initial measurement result, shall not exceed the critical change value. 7.2. the temperature sensor of the measurement result after the durability test changes, compared with the initial measurement result, shall not exceed 0,1 ° c. 8. write on the heat meter: 8.1. accuracy class; 8.2. flow-through limit values; 8.3. the temperature limit values; 8.4. the difference between the temperature limit values; 8.5. the flow sensor installation: inlet or atgait; 5.3. indication of the direction of the flow. 9. If the meter Kit from separate components, which are made by one or more manufacturers, the meters requirements apply also to individual parts and they comply with this annex 10, 11, 12, 13 and 14 the requirements set out in paragraph. 10. P lūsm's relative CPC, expressed as a percentage, depending on the accuracy class, are: class 1: Ef = (1 + 0.01 qp/q), but not more than 5%; class 2: Ef = (2 + 0.02 qp/q), but not more than 5%; class 3: Ef = (3 + 0.05 qp/q), but not more than 5% where the error Ef links indicated and true value of the relation between flow sensor output signal and mass or volume. 11. Temperature sensor over the relative MPE, expressed as a percentage: Et = (0.5 + ∆ ∆ θ θmin/3), which binds the indicated error and the Et the true value of the ratio between temperature sensor pair output and temperature difference. 12. the relative MPE of the Calculator, expressed as a percentage: Ec = (0.5 + ∆/∆ θ θmin) where the error Ec links indicated and true value of the heat energy. 13. the critical change value of the component parts is equal to the corresponding absolute value of the MPE applicable to individual components (this annex 10, 11 and 12). 14. write the meter component parts: 14.1. employer: 14.1.1. flow accuracy class; 14.1.2. flow-through limit values; 14.1.3. temperature limit values; 14.1.4. nominal meter factor (e.g. litres in relation to the pulse) or corresponding output signal; 14.1.5. indication of the direction of flow; 14.2. the temperature sensor pair: 14.2.1. type identification (e.g. Pt 100); 14.2.2. temperature limit values; 14.2.3. the difference between the temperature limit values; 14.3. computing: 14.3.1. temperature sensor type; 14.3.2. temperature limit values; 14.3.3. the difference between the temperature limit values; 14.3.4. the nominal meter factor (e.g. litres in relation to momentum) or the flow transducer output signal; 14.3.5. flow transducer mounting location: inlet or atgait. 15. If the meter is intended for use in residential buildings, measurement of any class 3 meter. 16. If the meter is designed for commercial use, light industrial or commercial and light industrial use, measurements, use any class 2 meter.
Economic Minister a. Štokenberg in