Unknown BS EN 14989 2 2007 ICS 91 060 40; 91 140 30 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW BRITISH STANDARD Chimneys — Requirements and test methods for metal chimneys[.]
General
Unless otherwise stated, performance requirements for fittings shall be the same as those for ducts Flue ducts for separate air/flue configurations shall meet the requirements of EN 1856-1.
Mechanical resistance and stability
Compressive strength
7.2.1.1 Flue and air supply ducts
The manufacturer shall declare the relevant design loads
In concentric air/flue configurations where the air supply duct serves as a load-bearing element, it is essential that the system can endure a load that is at least three times greater than the manufacturer's specified design load, as per the testing requirements outlined in section 12.1.1.1.
In concentric air/flue configurations where the flue duct serves as a load-bearing element, it must be capable of supporting a load that is at least four times greater than the manufacturer's specified design load, as per the testing requirements outlined in section 12.1.1.1.
For separate configurations the air supply duct when tested according to 12.1.1.1, shall withstand a load of at least three times the manufacturer’s declared design load
7.2.1.2 Flue and air supply duct supports
The manufacturer shall declare the relevant design loads
According to section 12.1.1.2, the air supply duct support and flue duct support must not exceed a maximum displacement of 5 mm in the direction of the load when subjected to the manufacturer's specified design load.
The support shall withstand an intensity of loading of at least three times the manufacturer's declared design load.
Tensile strength
The manufacturer shall declare the relevant design loads
According to section 12.1.2, components of the air/flue configuration specified by the manufacturer must be capable of supporting a load that is at least 1.5 times greater than the manufacturer's stated design load.
Lateral strength
When testing the concentric air/flue configuration or a separately configured air supply duct, which the manufacturer has approved for non-vertical installation, it is essential that the deflection of any part of the test sample does not exceed 2 mm per meter of distance between supports, as outlined in the installation instructions and the specified test method.
7.2.3.2 Components subject to wind load
When testing the concentric air/flue configuration or the separately declared air supply duct for external installation, as specified by the manufacturer, the test sample must endure a minimum load of 1.5 kN/m² based on the projected outer surface area, following the method outlined in section 12.1.3.2.
Resistance to fire
Internal to external
The manufacturer shall declare the minimum distance to combustible material according to 7.5.1.2.
External to external
Until a European test method is available the resistance to fire, external to external, shall be evaluated and declared according to national regulations.
Hygiene, health and environment
Gastightness of the flue duct
Flue duct testing must adhere to the methods outlined in section 12.2.1.2.2, ensuring that the leakage rate does not exceed the limits specified in Table 5 This requirement applies both prior to and following thermal performance tests, as well as after the sootfire test when applicable.
Gastightness of the air supply duct
When testing an air supply duct at a positive pressure of 40 Pa, the leakage must not exceed 0.28 lás-1 ãm-2 of the duct's surface area This requirement applies both before and after the thermal performance test, and, if applicable, after the sootfire test.
Safety in use
Thermal performance
NOTE A concentric air/flue configuration made of sections and/or fittings is thermal shock resistant when it meets the gas tightness after the thermal tests
7.5.1.2 Distance to adjacent combustible surfaces
The concentric air/flue configuration must be tested according to section 12.3.1.2.1, ensuring that the maximum temperature of nearby combustible materials does not exceed 85 °C in relation to the ambient temperature.
The sootfire resistant concentric air/flue configuration must be tested according to section 12.3.1.3.2 It is essential that the maximum temperature of nearby combustible materials does not exceed 100 °C when the ambient temperature is 20 °C.
7.5.1.3 Temperature of additional materials and components
All supplementary materials or components within the flue and air supply duct must undergo testing as per section 12.3.1.3.3 It is essential that the maximum temperature of these materials or components does not surpass their designated working temperature.
The flue/air supply duct and its components shall be tested in accordance with 12.3.1.3.4
No part of air/flue configuration or its components shall show any permanent deformation, blisters or cracks that may affect its performance
The elongation of the test air/flue configuration shall not exceed 0,005 m, and meet the gas tightness given in 7.4.1 and 7.4.2
In situations where accidental human contact with a flue may occur, the outer wall surface temperature of the concentric air/flue configuration must not exceed the specified limits outlined in Table 1, as measured during the test of 12.3.1.3.1.
Table 1 — Maximum outer wall surface temperatures
Material of the outer surface Maximum allowed temperature
Double Sided Vitreous/Porcelain Enamelled
NOTE The values in Table 1 are based on the criteria in EN ISO 13732-1, relating to a 1 s burn threshold.
Thermal resistance
7.5.2.1 Flue/air supply ducts with concentric air/flue configuration
The thermal resistance value of the flue duct, expressed in [m² K/W], must be verified through testing and calculations as specified in sections 12.3.2.2.1 and 12.3.2.2.2, unless the manufacturer declares the thermal resistance to be zero.
The thermal resistance value of the air supply duct, as declared by the manufacturer, must be verified through testing and calculations, unless the declared thermal resistance is zero This verification should follow the guidelines outlined in sections 12.3.2.2.1 and 12.3.2.2.3.
Rainwater ingress
7.5.3.1 Air supply duct for all systems
When the air supply duct is tested according to the test methods described in 12.3.3.1 or 12.3.3.2, there shall be no water entering the air supply duct
Products which fail this requirement may be designated rain water resistant if an adequate drain is provided
If a manufacturer provides a drain it shall be included in the test assembly prior to test The drain shall prevent rainwater entering the appliance
Flow resistance of the flue and air supply ducts and fittings
7.5.4.1 Mean value of roughness of straight ducts
The manufacturer shall declare the mean value of roughness for straight concentric and separate flue ducts and straight separate air supply ducts Typical values are given in Table 2
For concentric air supply ducts the flow resistance shall be measured according to 12.3.4
Table 2 — Typical values for mean roughness r for flues and air supply ducts
Materials of the flues and air supply ducts Typical values for mean roughness, r m
Enamelled Steel(DSVPES) 0,00004 welded steel 0,001 glass 0,001 plastic 0,001 aluminium 0,001 clay ceramic flue liners 0,0015 bricks 0,005 soldered metal 0,002 concrete 0,003 masonry 0,005 corrugated metal 0,005
Where the materials of the air supply ducts are different, the higher roughness value of the surfaces shall be used
The manufacturer shall declare the flow resistance of fittings
The declared value is determined using the test method outlined in section 12.3.4, following the conditions specified in 12.3.4.1 For flue duct fittings and non-concentric air supply duct fittings, the value can be obtained from the data provided in Table B.1.
Water vapour diffusion resistance
When testing a section or fitting designed for wet operating conditions and gas tightness class N1 according to method 12.3.5, it is essential that the outer surface remains dry, and the mass increase of the section or fitting must not exceed 1.0% of the insulating material.
Condensate penetration resistance
When testing a straight flue duct or fitting designed for wet operating conditions according to method 12.3.5, it is essential that the outer surface remains dry Additionally, the mass increase of the section or fitting must not exceed 1.0% of any insulating material.
Materials
Flue ducts and other parts in contact with combustion products
Flue ducts and other parts in contact with combustion products shall be in accordance with Table 4.
Air supply duct and other parts not in contact with combustion products
Air supply ducts and other parts not in contact with combustion products shall consist of materials - protected or not - which are to be regarded as fit for the purpose, e.g.:
galvanized steel, according to the Sendzimir process, with a minimum zinc layer weight of 275 g/m 2 ;
When selecting materials for air supply ducts, it is essential to consider the potential for corrosion due to the recirculation of flue gas, which may contain harmful constituents.
Additional information on plastics and elastomers
Attention shall be paid to the resistance to sunlight where appropriate, in particular UV radiation, as well as to flame extinction and flame sustainability
Plastics and elastomeric components in the duct must not exhibit any deformation, whether permanent or temporary, that could impact the performance of the air/flue configuration when tested according to section 12.4 Additionally, these materials must comply with the requirements specified in EN 14241-1 during flue duct assessments conducted at the temperatures outlined in section 12.3.1.3.3.
Freeze/thaw
Metal products are considered deemed to satisfy free freeze/thaw resistance
Plastic components satisfying the requirement 7.6.3 a) are also considered deemed to satisfy the freeze/thaw resistance
Other components of, e.g clay, ceramic, concrete shall meet the relevant requirement in the relevant product standard
Manufacturer's instructions
The manufacturer’s instructions shall be available in the language of the country of destination.
Minimum information to be included in the manufacturer's instructions
nominal diameters of the flue duct and air supply duct;
actual diameters and lengths of the spigots with tolerances;
maximum installation lengths or weight of the flue and air supply duct;
typical installation drawing, vertical or non-vertical, external or internal;
identification of flue and air supply ducts;
minimum distance to combustible materials;
information required on the chimney plate;
that the product shall be installed in accordance with local rules in force;
A.1 for the calculation of the pressure loss the mean value of roughness for the material of the flue, r, in mm,
A.2 for the coefficient of flow resistance due to a dimensional and / or cross sectional change in the flue, ζ;
reaction to fire (only for plastic components); and where appropriate:
method of installation of any seals required;
specific methods or tools for cleaning
NOTE The normal method of cleaning is by the use of a brush which should not be made from black steel.
Appliance adapter
Where appropriate an adapter shall be provided with a flue gas and air entry sampling point
General
NOTE For CE marking and CE labelling purposes the provisions of ZA.3 apply.
Flue and air supply duct
The flue and air supply duct must be clearly marked with essential information, including the product designation as per Clause 10, the manufacturer's name or trademark, the manufacturing batch or product reference, and the identification of the flue duct If marking on the product is not feasible, this information should be provided on the label or packaging.
Packaging
Each package in a consignment must be clearly labeled with essential information, including the product designation as specified in Clause 10, the manufacturer's name or trademark, and the nominal diameters of both the flue duct and air duct.
Chimney plate
The manufacturer must provide a durable chimney plate that includes essential information: the manufacturer's name or trademark, a designated space in accordance with EN 1443, the nominal diameter of the flue and air supply ducts, the minimum distance to combustible materials marked in millimeters with an arrow and flame symbol, and a section for the installer's details and installation date.
General
The concentric air/flue configuration or the flue duct of the separate air/flue configuration shall be designated in accordance with the following designation system:
Flue/air supply duct EN xx T120 - P1 - D - Vm - L40045 - O50
Resistance to condensate class (W: wet /D: dry)
Flue duct material specification (see 10.5.2)
Soot-fire resistance class (G yes or O no) and distance to combustible material in mm (see 10.6)
Temperature classes and test temperature
Table 3 identifies the temperature class for the flue duct nominal working temperature, and gives the test temperature for the temperature level
Table 3 — Temperature classes and test temperatures
Flue gas test Temperature ºC
Pressure class
Flue ducts to this standard are designated according to pressure classes N1, P1, P2, H1 or H2.
Condensate resistance class
Flue duct shall be designated either:
W – for flue duct operating under wet operating conditions;
D – for flue/air supply duct operating under dry operating conditions.
Corrosion resistance
Corrosion resistance
Corrosion resistance can be determined based on either the material type and thickness of the flue duct, as outlined in Table 4, or through the results of at least one of the three test methods specified in normative Annex A.
Products which have a declaration on the basis of material type and thickness shall be designated Vm
Products passing the test described in A.1 of EN 1856-1:2003 shall be designated V1
Products passing the test described in A.2 of EN 1856-1:2003 shall be designated V2
Products passing the test described in A.3 of EN 1856-1:2003 shall be designated V3
The product designation shall, in any case, include the flue duct material specification, according to 10.5.2
NOTE The link between Vm, V1, V2 and V3 and the allowed use is dependent on individual member states regulations, where they exist.
Flue duct material specification
The flue duct's complete material specification is denoted by the letter L followed by a five-digit code The initial two digits indicate the material type as outlined in Table 4, while the final three digits represent the material thickness in millimeters, expressed in multiples of 0.01.
EXAMPLE L 40045 represents a liner made of 1.4401 stainless steel with a thickness of 0,45 mm
Table 4 — Flue duct material specification
Material type Material Nº Symbol
EN AW Al Si 12A a (cast aluminium)
EN AW Al Mg Si X5CrNi 18-10 X2CrNi 18-9 X5CrNiMo 17-12-2 X2CrNiMo 17-12-2 X2CrNiMo 17-12-3
DSVPES(Double Sided Vitreous/Porcelain Enamelled Steel)
1) With maximum contents Cu < 0,1% and Zn < 0,15%
2) Equivalent for material Nº 1.4404 = 1.4571(symbol X6CrNiMoTi 17-12-2)
3) A material type not currently specified in the table (and assigned a material number) may be assigned the material type 99 for the purpose of designating the product It may be considered as a suitable liner material provided that it has passed the appropriate corrosion test according to its intended designation V1, V2, or V3 The manufacturer shall declare the material specification.
Resistance to fire – Soot fire resistance, and distance to combustible material
The flue duct shall be designated O if it is non sootfire resistant or G if it is sootfire resistant, followed by the separation distance to combustible material xx, in mm
General
The compliance of a product duct with the requirements of this European Standard and with the stated values (including classes) shall be demonstrated by:
factory production control by the manufacturer, including product assessment.
Type testing
Initial type testing (ITT)
Initial type testing must be conducted to demonstrate compliance with this European Standard Previous tests that align with the standard's provisions—covering the same product, characteristics, test methods, sampling procedures, and conformity assessment systems—can be considered Furthermore, initial type testing is required at the start of new product production or when a new production method is introduced that may impact the declared properties.
Characteristics based on conformity with product standards for insulation materials, metals, coatings, seals, and sealants do not require reassessment if the designer validates the results CE marked products that comply with relevant harmonised European specifications are presumed to meet their stated performance However, this does not absolve the manufacturer of the responsibility to ensure the overall design and performance values of all components.
All characteristics defined in Clauses 5, 6 and 7 shall be subject to initial type testing, with the following exception:
release of dangerous substances which may be assessed indirectly by controlling the content of the substance concerned.
Further type testing
Any modifications to product design, raw materials, suppliers, or production processes that affect the tolerances or requirements outlined in Clauses 6 and 7 necessitate the repetition of type tests for the relevant characteristics.
Sampling for type testing
The size of products to be tested shall be according to Annex C
The quantity of products to be tested for each size must adhere to the specifications outlined in Annex D Manufacturers are required to document and retain the results of all type tests until they are replaced by new data.
Factory production control (FPC)
General
A FPC system that adheres to the applicable sections of EN ISO 9001:2000 and is tailored to the products specified in this European Standard is deemed to meet the necessary requirements.
The manufacturer must create, document, and uphold a Factory Production Control (FPC) system to guarantee that the products meet the specified performance characteristics of the type test sample This FPC system should include established procedures, routine inspections, tests, and assessments, utilizing the results to manage raw materials, components, equipment, the production process, and the final product.
The manufacturer must ensure the effective implementation of the factory production control system, with clearly documented and up-to-date tasks and responsibilities In each factory, the manufacturer can delegate these responsibilities to an authorized individual.
identify procedures to demonstrate conformity of the product at appropriate stages;
identify and record any instance of non-conformity;(c) identify procedures to correct instances of non conformity
The manufacturer must create and maintain current documentation outlining the factory production control (FPC) systems in use These documents and procedures should be tailored to the specific product and manufacturing process It is essential that all FPC systems instill a sufficient level of confidence in the product's conformity.
the preparation of documented procedures and instructions relating to factory production control, operations, in accordance with the requirements of the reference technical specification;
the effective implementation of these procedures and instructions;
the recording of these operations and their results;
The results will be utilized to address any deviations, remedy their effects, manage instances of non-conformity, and, if required, update the FPC to eliminate the root cause of the non-conformity.
The production control operations shall include some or all of the following operations:
the specification and verification of raw materials and constituents;
the controls and tests to be carried out during manufacture according to a frequency laid down;
Finished products must undergo verifications and tests at a frequency specified in the technical specifications, tailored to the product and its manufacturing conditions.
Depending on the specific case, it may be necessary to perform various operations, which can include either a combination of intermediate state assessments and equipment adjustments or focus solely on one of these aspects The operations related to intermediate states emphasize the importance of manufacturing machines, their adjustments, and associated equipment The selection of controls, tests, and their frequency is determined by factors such as the product type, composition, manufacturing process complexity, and the sensitivity of product features to variations in manufacturing parameters.
The manufacturer must possess or have access to the necessary facilities, equipment, and personnel to perform required verifications and tests This requirement can also be fulfilled by the manufacturer or their agent through subcontracting agreements with qualified organizations or individuals who have the appropriate skills and equipment.
The manufacturer is responsible for calibrating, verifying, and maintaining control, measuring, or test equipment in optimal working condition, regardless of ownership, to ensure the product meets its technical specifications This equipment must be utilized in accordance with the relevant specifications or test reference systems.
If necessary, monitoring shall be carried out of the conformity of intermediate states of the product and at the main stages of its production
This monitoring of conformity focuses where necessary on the product throughout the process of manufacture, so that only products having passed the scheduled intermediate controls and tests are dispatched
Inspection, testing, and assessment results that necessitate action must be documented, along with any actions taken Additionally, it is essential to record the actions required when control values or criteria are not satisfied.
Equipment
All weighing, measuring and testing equipment shall be calibrated and regularly inspected according to documented procedures, frequencies and criteria.
Raw materials and components
The specifications of all incoming raw materials and components shall be documented, as the inspection scheme for ensuring their conformity.
Product testing and evaluation
The manufacturer must implement procedures to maintain the stated values of product characteristics For guidance on sampling for Factory Production Control (FPC), refer to Annex D, while the specific characteristics of the components are detailed in Annex E.
Non conforming products
The manufacturer shall establish procedures for non conforming products
Mechanical resistance and stability
Compressive strength
12.1.1.1 Flue and air supply ducts
Assemble the components following the manufacturer's installation instructions, which include two adapters and one straight section (refer to Figure 1 a)) The adapters, provided by the air/flue configuration manufacturer, must effectively transfer the test load to the load-bearing wall of the test components, mirroring the installation process The test load is conveyed to the test components using a pivoted plate.
Increase the test load on the components without shock
For concentric air/flue configurations where the air supply duct is load bearing increase the load up to three times the manufacturer’s design load
For concentric air/flue configurations where the flue duct is load bearing increase the load up to four times the manufacturer’s design load
For separate configurations the air supply duct increases the load up to three times the manufacturer’s design load
The load shall be measured to an accuracy of 2 % of the design load The result shall be recorded
When the design load is uncertain, it is essential to uniformly increase the test load and document the outcomes to identify the failure point A failure is considered to have occurred when the components can no longer withstand an additional increase in load.
To determine the design load, utilize the minimum value from three failure loads: a) the compressive strength on the fitting (refer to section 4.1.1.1), b) the compressive strength on the air/flue configuration support (see section 4.1.2.1), and c) the tensile strength on the air/flue configuration section (refer to section 4.2.1).
Figure 1 — Structural test configurations 12.1.1.2 Supports
Increase the test load up to the design load without shock Record the maximum displacement of the support Measure the displacement to an accuracy of 0,1 mm
Further increase the load up to three times the design load
Measure the load to an accuracy of 2 % of the design load
When the design load is uncertain, it is essential to uniformly increase the load and document the outcomes to identify the failure point A failure is considered to have occurred when the support can no longer handle an additional load increase.
Record the displacement during the load increase Use the minimum value from three failure loads The design load shall be at most 1/3 of the minimum failure load.
Tensile strength
Install straight sections following the manufacturer's guidelines, and apply the test load using a manufacturer-supplied adapter, which will effectively transfer the load to the load-bearing wall of the straight sections.
Increase the test load on components gradually, reaching up to 1.5 times the design load without causing shock Ensure that the load is measured with an accuracy of 2% of the design load, and document the results accordingly.
When the design load is not specified, it is essential to gradually increase the test load and document the outcomes to identify the failure point A failure is considered to have occurred when the fitting is unable to support any additional load.
Use the minimum value from three failure loads to determine the design load.
Lateral strength
Install the test sample and supports at the maximum angle from vertical, ensuring the supports are positioned at the maximum distance apart (Lmax) as per the manufacturer's installation guidelines Utilize additional vertical supports to maintain the sections without deflection (refer to Figure 2).
Remove the additional vertical supports The maximum deflection to an accuracy of 0,1 mm shall be recorded
2 original supports proposed by manufacturer
Lmax maximum distance between supports a maximum angle from vertical
Figure 2 — Examples for positioning of supports (Lmax) 12.1.3.2 Wind loading
Install the air and flue configuration components following the manufacturer's guidelines Utilize the test assembly with the manufacturer's specified freestanding components and additional air/flue configuration sections, ensuring compliance with the maximum lateral support separation distance between supports and up to an anchor point, as illustrated in Figure 3.
C manufacturer's declared maximum wall bracket separation distance
D distance over which the load is distributed = A + C + C/2
Figure 3 — Wind load test assembly 12.1.3.2.2 Procedure and results
Apply an evenly distributed test load increased uniformly up to 1,5 kN/m 2 ± 2,5%
NOTE A method for applying an evenly distributed load is described in Annex H of EN 1859:2000 Other methods using a vertical assembly can also be used
Apply the test load to those components declared by the manufacturer for external use, except 50 % of the last laterally supported section of the test assembly
To conduct the test load, apply several individual evenly distributed loads, ensuring they are spaced no more than (0.2 ± 0.01) m apart from the freestanding end The variation among the individual loads must not exceed 1% Record all results accurately.
Hygiene, health and environment
Gastightness
To ensure accurate measurements, connect a positive pressure air supply and a flow meter with a maximum measuring error of 2% to the flue or air supply duct Additionally, attach a manometer to the duct of the test assembly for pressure measurement.
Seal one end of the flue duct Connect a positive pressure air supply, flow meter and manometer to the other end of the flue duct with appropriate air-tight seals
For class P1 flue ducts deliver air from the positive pressure air supply to the flues duct at a constant pressure of 200 Pa ± 2%
Measure the flow rate into the flue duct
For class H1 flue ducts deliver air from the positive pressure air supply to the flue duct at a constant pressure of 5 000 Pa ± 2 %
Measure the flow rate into the flue duct
Table 5 — Leakage rate Pressure type Test pressure
Leakage rate/Flue surface area l ã s -1 ã m -2
12.2.1.2.3 Gastightness of the air supply duct
Deliver air from the positive pressure air supply to the air supply duct at a constant pressure of 40 Pa ± 2 % Measure the flow rate into the air supply duct
The air flow rate shall be recorded.
Safety in use
Thermal performance
The test assembly shall comprise a test structure (see 12.3.1.1.2), a test air/flue configuration (see 12.3.1.1.3), a hot gas connecting pipe (see 12.3.1.1.4) and measuring equipment (see 12.3.1.1.5)
Construct a test structure featuring two perpendicular walls and two floors, allowing the test air/flue configuration to pass through This structure should adhere to the specifications outlined in sections 12.3.1.1.2.2 and 12.3.1.1.2.3, or possess equivalent thermal characteristics and dimensions The area beneath the first floor is designated as Zone A, the space between the first and second floors as Zone B, and the area above the second floor as Zone C, as illustrated in Figure 4.
The wall and floor interface will be equipped with a skirting board measuring 20 mm by 100 mm In Zones A and B, the vertical distance between the floor and ceiling is specified to be 2,400 mm with a tolerance of ± 25 mm Additionally, timber materials must adhere to a dimensional tolerance of +1 mm.
Construct walls using 38 mm × 89 mm thick timbers in a framework, faced on both sides with a single layer of 12 mm thick plywood, resulting in a total thickness of 114 mm The voids should be insulated with mineral fibre insulant, which has a thermal conductivity of 0.035 W/m K ± 0.002 W/m K at 20 °C and a minimum density of 70 kg/m³ The walls must extend 1,200 mm.
Figure 4 a) — Wall Frame A Side 1 Zone A Figure 4 b) — Wall Frame B Side 2 Zone A
Figure 4 c) — Wall Frame C Side 1 Zone B Figure 4 d) — Wall Frame D Side 2 Zone B
Material: Kiln dried softwood sawn and planed 89X38 (Tolerance ± 1)
Figure 4 — Framework for thermal performance test
Construct the flooring framework using nominal dimension timbers of 50 mm × 200 mm for the first floor and 50 mm × 100 mm for the second floor Ensure the design includes an opening that allows for the installation of the test air/flue configuration, maintaining a clearance of X mm from all parts of the test structure as specified by the manufacturer (refer to Figure 4 e)).
Construct the floor in Zone A and Zone B by covering the top of framework in Zone A and Zone B with one thickness of boarding of nominal dimension 20 mm
Construct the ceiling in Zone A and Zone B by covering the underside of the Framework in Zone A and Zone B with one thickness of plywood of nominal dimension 12 mm
Leave the top of the framework in Zone C exposed, and at each level fill the spaces between the timbers with
100 mm thick mineral wool slab with a thermal conductivity of 0,035 W/m K ± 0,002 W/m K at 20 °C, with a minimum density of 70 kg/m 3
Construct the test air/flue configuration using the components materials and construction representing the manufacturer's product range, e.g sections, T pieces and inspection openings
Ensure the air/flue configuration aligns with the test assembly as per the manufacturer's instructions, incorporating fire-stops or spacers appropriately, as illustrated in Figures 5a and 5b.
a minimum of seven joints are between the floor of Zone A and 900 mm into Zone C;
the combustion products are taken to where they cannot contaminate the inlet air (temperature and combustion products);
the mass flow in the air supply duct shall be equal to the mass flow in the flue duct;
for the sootfire test the mass flow in the air supply shall be zero
X manufacturer's declared distance to combustibles
Figure 5 a) — Thermal performance, test air/flue configuration with straight sections
X manufacturer's declared distance to combustibles
Figure 5 b) — Thermal performance, test air/flue configuration with offset
Figure 5 — Thermal performance test – Test air/flue configuration
Where a manufacturer’s product range includes bends, the test air/flue configuration shall include one offset (see Figure 5 b)), with an offset angle of maximum 45° and an offset distance of 0,75 m ± 0,25 m
Construct a specialized insulated straight flue pipe with an internal diameter matching that of the flue in the test air/flue configuration The pipe should be approximately seven diameters (7D) long, measured from the outlet of the flue gas generator to the entry of the test air/flue configuration Ensure the insulation provides a thermal resistance equivalent to at least 50 mm of material with a thermal conductivity of 0.125 W/m K ± 0.005 W/m K at 750 °C.
NOTE This item should be supplied by the air/flue configuration manufacturer
12.3.1.1.5 Measuring equipment and its location
Measure ambient air temperature with an accuracy of ± 1.5 °C, positioning sensors 300 mm ± 5 mm below the ceiling in Zone A and 300 mm ± 5 mm above the floor in all other zones For non-enclosed air/flue configurations, add ambient measuring points at levels that correspond to the outer surface temperature measurements.
To measure ambient temperature accurately, a calibrated thermocouple is shielded by positioning it centrally within a 150 mm ± 2 mm long and 50 mm nominal diameter aluminum-painted metal tube, which is open at both ends At each measurement level, two tubes are positioned 600 mm ± 5 mm from the test air/flue configuration surface on opposite sides of the test assembly The thermocouple is oriented vertically to prevent direct radiation from affecting its readings.
Measure the hot gas temperature with an accuracy of ± 3 °C for hot gas temperatures less than or equal to
Hot gas temperatures exceeding 600 °C should be measured at a location 50 mm ± 2 mm before the inlet to the test air/flue configuration, specifically at the point in the cross section where the highest temperature is recorded, with an accuracy of ± 0.75%.
The method for hot gas temperature measurements is to use a calibrated thermocouple Its position is determined by a temperature traverse undertaken during the first thermal cycle as follows:
Position the hot gas thermocouple at the center of the flue pipe using one of the two provided apertures, ensuring it is set at a height of 50 mm ± 2 mm from the entry point of the test air/flue configuration.
Fire the hot gas generator at the volume flow specified in Table 6 and adjust to produce the specified hot gas test temperature
After a minimum of 10 minutes of firing, measure the temperature at ten equally spaced points along two perpendicular traverses across the flue pipe's cross section, ensuring that measurements are taken no closer than 12 mm from the flue wall.
Determine the location of the highest temperature of these two traverses and position the thermocouple there for the test
Re-adjust the hot gas generator to obtain the specified hot gas temperature
Alternatively a thermocouple grid may be used to determine the OTDF
Measure the surface temperature of components with an accuracy of ± 1,5 °C
Measure the surface temperature of the adjacent wood/combustible parts of the test structure with an accuracy of ± 1,5 °C
To measure the surface temperature of combustible wood, thermocouples with a maximum wire diameter of 0.56 mm are utilized These thermocouples should have an exposed length of 13 mm ± 2 mm, which is inserted through designated holes in the structure The exposed sections are then bent over and pressed flush against the surface, secured in place by staples positioned near the thermocouple junction.
12.3.1.1.5.5 Locations for surface temperature measurements
Establish the maximum temperature of the surfaces of the test structure and the test air/flue configuration during the thermal cycle appropriate to the designation
Locations for thermocouples are described in Figure 6
Figure 6 — Test structure – Location of surface temperature on the test structure
Measure the flue gas volume to an accuracy of
Flue gas volume flow measurements can be conducted using various techniques, including the use of a Pitot tube in accordance with BS 1042-2.1, or by employing orifice plates and gas analysis methods.
The test room shall consist of a ventilated space not subject to draughts greater than 0,5 m/s measured at the ambient thermocouple positions (see 12.3.1.1.5.1)
Ambient temperature within the test building shall be maintained within the limit of 15 °C to 30 °C, measured at the designated ambient temperature positions (see 12.3.1.1.5.1)
The humidity shall be controlled between 30 % RH to 70 % RH
Ambient air shall be able to circulate freely between all parts of the test room
The distance between the test assembly and other structures (e.g test room walls) shall be at least 1,0 m
Install the air/flue configuration components in the test assembly which is appropriate to the manufacturer's declared product location designation
Encase the air/flue configuration intended for internal use, which has a combustible enclosure in Zone B, with 12 mm nominal dimension plywood on the remaining two sides Ensure that the installation adheres to the manufacturer's specified clearance between the outer surface of the air/flue configuration sections and the interior surface of the enclosing materials.
Ensure that the clearance, indicated by dimension X in Figure 5, is properly maintained Seal all floor penetrations at both ceiling and floor levels using a fire-stop or a fire-stop and spacer system provided by the manufacturer.
Seal only joints and openings between spacers or supports and the test structure and all joints in the enclosure casing
Thermal resistance
12.3.2.1 Flue/air supply ducts with concentric flue/air configuration
Fit the flue/air supply duct in accordance with the manufacturer instructions to the test assembly, Figure 5,
12.3.1.1 The fan and heat input to the heat generator are adjusted, and measured at measuring point Te such that hot air enters the flue duct at a temperature equal to the test temperature of the duct as given in
The air temperature entering the duct at measuring point TeB, as shown in Figure 7, must be maintained at (20 ± 5) °C Additionally, it is important to monitor the temperatures at the air supply inlet (TeB), air supply outlet (ToB), flue inlet (Te), and flue outlet.
To shall be recorded and used for the calculation of the thermal resistance
3 air supply passage (with supply air)
See Clause 4 for other symbols
Figure 7 — Definition of the symbols used for the calculation of concentric balanced flue systems
12.3.2.1.2 Calculation of the thermal resistance of the flue duct
For the calculation of the coefficient of heat transmission between the flue and the air supply passage for concentric ducts, the following equation shall be used: rad a ha
1 is the thermal resistance of the flue duct in
W m 2 ⋅ K k b is the coefficient of heat transmission between the flue and the air supply passage at temperature equilibrium in
2 ⋅ αi is the coefficient of heat transfer between the flue gas and the inner surface of the flue duct in
2 ⋅ αa is the coefficient of heat transfer between the supply air and the outer surface of the flue duct in
D h is the hydraulic diameter of the flue in m
D ha is the hydraulic diameter of the outside of the flue duct in m
S rad is the correction factor for radiation from the outer surface of the flue duct to the inner surface of the air supply duct
For the calculation of the coefficient of heat transmission between the flue and the air supply passage at temperature equilibrium k b the following equations shall be used:
V • is the test flow rate in s m 3 ρe is the density of air for T e in 3 m kg c p is the specific heat capacity of air for T m in
T e is the air temperature at the flue inlet in °C
T o is the air temperature at the flue outlet in °C
U is the circumference of the inside of the flue in m
L is the length of the test segment in m
T m is the mean temperature in the flue in °C
T mB is the mean temperature in the air supply in °C
T eB is the air temperature at the air supply inlet in °C
T oB is the air temperature at air supply outlet in °C
For the calculation of the coefficient of heat transfer between the flue gas and the inner surface of the flue duct αi the following equations shall be used: h i
Pr - (10) where αi is the coefficient of heat transfer between the flue gas and the inner surface of the flue duct in m W 2 ⋅ K λA is the thermal conductivity of air for T m in m W ⋅ K
Nu is the Nusselt number for the flue -
D h is the hydraulic diameter of the flue in m ψ is the coefficient of friction of the flue - ψsmooth is the coefficient of friction of the flue for hydraulically smooth flow -
Re is the Reynolds number of the flue -
Pr is the Prandtl number of the flue -
The length of the test segment is denoted as \(L\) in meters, while \(r\) represents the mean roughness value of the inner wall of the flue duct, also measured in meters The average velocity of air within the flue is indicated by \(w_m\) in seconds per meter, and the density of air at temperature \(T_m\) is expressed as \(ρ_m\) in kilograms per cubic meter Additionally, the dynamic viscosity of air at temperature \(T_m\) is represented by \(η_A\) in square meters per second.
For the calculation of the coefficient of heat transfer between the supply air and the outer surface of the flue αa the following equations shall be used: hB a
The coefficient of heat transfer between the supply air and the outer surface of the flue duct is denoted as αa, measured in m W/(2 ⋅ K) Additionally, λB represents the thermal conductivity of air at temperature T mB, also expressed in m W/(K).
Nu a is the Nusselt number for the outside of the flue duct -
D hB is the hydraulic diameter of the air supply passage in m
A B is the cross-sectional area of the air supply passage in m²
U iB is the circumference of the inside of the air supply duct in m
U a is the circumference of the outside of the flue duct in m
D ha is the hydraulic diameter of the outside of the flue duct in m
The Nusselt number for a reference pipe flow is denoted as Nu B The variable ψB represents the higher value of the coefficient of friction for the inside of the air supply duct compared to the outside of the flue duct Additionally, ψsmoothB refers to the coefficient of friction for hydraulically smooth flow within the air supply.
Re B is the Reynolds number of the air supply passage -
Pr B is the Prandtl number of the supply air -
The length of the test segment is denoted as \( L \) in meters The variable \( r \) represents the higher mean roughness value of both the inside of the air supply duct and the outside of the flue duct, measured in meters The average velocity of the supply air is indicated by \( mB \) in seconds per meter, while \( \rho mB \) refers to the air density at temperature \( T mB \) in kilograms per cubic meter Additionally, \( \eta B \) signifies the dynamic viscosity of air at temperature \( T mB \) in square meters per second.
N ⋅ c pB is the specific heat capacity of air for T mB in k g J ⋅ K
To accurately assess the impact of radiation from the outer surface of the flue duct to the inner surface of the air supply duct, the heat transmission coefficient, \( k,j \), must incorporate a correction factor for radiation, denoted as \( S_{rad} \), with a value of 2.
12.3.2.1.3 Calculation of the thermal resistance between the supply air and the ambient air
For the calculation of coefficient of heat transmission between the supply air and the ambient air the following equation shall be used: aB haB hiB iB
1 is the thermal resistance of the air supply duct in
The coefficient of heat transmission between the supply air and the ambient air at temperature equilibrium is denoted as \( W \, m^{-2} \cdot K \) Additionally, the coefficient of heat transfer between the supply air and the inner surface of the air supply duct is represented as \( \alpha_iB \) in \( m \, W^{-2} \cdot K \).
D haB is the hydraulic diameter of the outside of the air supply duct in m
The hydraulic diameter (\$D_{hiB}\$) of the air supply duct is measured in meters, while the heat transfer coefficient (\$α_{aB}\$) represents the rate of heat transfer between the duct's exterior and the surrounding ambient air, expressed in watts per square meter per Kelvin.
For the calculation of the coefficient of heat transmission between the supply air and the ambient air at temperature equilibrium kBb the following equation shall be used:
( mB u ) iB eb oB pB o e p e
2 (20) with TmB according to Equation (4) where
V • is the test flow rate in s m 3 ρe is the density of air for T e in 3 kg m c p is the specific heat capacity of air for T m in k g J ⋅ K
T e is the air temperature at the flue inlet in °C
T o is the air temperature at the flue outlet in °C c pB is the specific heat capacity of air for T mB in k g J ⋅ K
T eB is the air temperature at the air supply inlet in °C
T oB is the air temperature at air supply outlet in °C
U iB is the circumference of the inside of the air supply in m
L is the length of the test segment in m
T mB is the mean temperature in the air supply in °C
T u is the ambient air temperature in °C
For the calculation of αiB the following equation shall be used: hB iB
D (22) and DhB according to Equation (13) and NuB according to Equation (14), where λB is the thermal conductivity of air for t mB in
NuiB is the Nusselt number for the inside of the air supply duct -
NuB is the Nusselt number for a reference pipe flow -
D hB is the hydraulic diameter of the air supply passage in m
D hiB is the hydraulic diameter of the inside of the air supply duct in m
D ha is the hydraulic diameter of the outside of the flue duct in m
Rainwater ingress
The rainmaking installation is made up of parallel pipes in a horizontal plane The tubes have small spray holes (placed vertically downwards)
The spray holes are uniformly positioned above the wire mesh, allowing water to be distributed through a fine wire mesh measuring 1.3 ± 0.1 mm in width, resulting in the water falling as raindrops A typical configuration is illustrated in Figure 8.
Figure 8 — Rainwater ingress test with wind assembly
The rain intensity is measured at (1.6 ± 0.2) mm/min Calibration reveals a specific area in front of the wind generator where this rain intensity is consistent Additionally, the maximum area of the flue top and air supply duct should not exceed 20% of the calibrated area.
The wind generator supplies a horizontal airflow at a velocity of (12 ± 0,5) m/s at the position of the product under test The outlet of the wind generator shall be square or circular
Before starting the rain ingress tests, it is essential to calibrate the test assembly This involves placing five buckets, each with a diameter of 150 mm, at designated positions: one in each corner of a rectangular area and one in the center The buckets should be positioned at a height that aligns with the midpoint between the flue gas outlet and the air inlet.
Ensure that the maximum area of the flue and air supply duct's top is under 20% of the area defined by the circumferential line of the buckets Begin the calibration test for 10 minutes in windy conditions and assess if the rain intensity is within the range of (1.6 ± 0.1) mm/min by weighing the five buckets.
Seal the duct outlet in alignment with the wind generator's outlet opening, as shown in Figure 8 Activate the wind and rain system, then measure and document the water quantity from the duct, along with the mass increase for insulated ducts, ensuring compliance with the requirements of section 7.5.3.
Chimney sections located in Zone C must undergo a thermal performance test as specified in section 12.3.1.2, with a minimum duration of 48 hours in the test environment Each section must have at least one joint, which should remain undisturbed after the thermal performance test when the sections are removed in their assembled state.
The test structure will feature a rotating, free-draining plinth with a perforated spray tube designed to direct jets of water towards the center of the circle Sections should be installed at the center of the plinth, ensuring that the center of the spray arc aligns with the center of the flue below or is level with the joint, as illustrated in Figure 9.
Seal the joint where the sections stand on the plinth and cover the top to prevent ingress of water into open end of section
The spray tube shall be constructed and dimensioned to allow the flow conditions of EN 60529 to be achieved and maintained
4 seal to prevent ingress of water into open end of section
Figure 9 — Rainwater ingress test with arc/spray apparatus 12.3.3.2.3 Spray procedure
Measure the weight increase of the sections with an accuracy of ± 0.5 g Spray water for 60 minutes ± 1 minute while oscillating the spray arc through an angle of 120° ± 5° (30° on either side of the vertical) and rotating the plinth Each complete traverse, consisting of two 120° sweeps, should take 6 seconds ± 1 second, while one full revolution of the plinth should last 5 minutes ± 1 minute Ensure to remove any surface moisture from the chimney sections before recording the results.
The sections may be separated to facilitate removal of surface moisture Reweigh the test sections
Record the increase in weight of the test sections The requirements of 7.5.3 shall be met.
Flow resistance of the flue and air supply ducts
The air velocity in the tested components must be adjusted to ensure that the airflow rate matches the nominal flow rate, which is determined by the actual inside diameter of the fittings.
The nominal flow rate is a function of the nominal diameter and the nominal velocity, where
Vnom is the nominal air flow rate, in square meters per hour;
Dn is the nominal diameter, in meters; wn is the nominal velocity, in meters per second
2 flange restriction for adjusting transport
Figure 10 — Flow resistance test assembly
A fitting is attached to both ends of a measuring duct that facilitates the supply and discharge of test air These measuring ducts must maintain a straight length of at least 2,000 mm and, with the exception of testing adaptors, should have a uniform diameter.
Pressure measuring points are strategically located in the measuring ducts, featuring at least three evenly distributed openings with a 1 mm diameter around the duct's circumference These openings are positioned opposite each other in a plane perpendicular to the duct's center line and must be free of burrs on the inside The average static pressure within the duct is accurately measured through these openings.
To ensure accurate pressure measurements, the measuring ducts must be designed to allow for undisturbed flow This requires that the length of the ducts, the placement of pressure measuring points, and their positioning relative to connected fittings and other supply and flue ducts maintain a distance of 7 Dn upstream and 3 Dn downstream from the measuring point.
To measure the flow resistance of the air supply duct in a concentric air/flue configuration, connect a section of pipe with the same outside diameter as the central flue pipe to both ends of the fitting being tested This pipe should extend the full length of the measuring duct and be sealed at the end opposite the fitting.
NOTE Sealing of the central pipe is to prevent air entering the flue pipe of the fitting under test
Ensuring a proper connection between the outlet, fan, and seal end of the central pipe in the measuring duct is crucial for achieving a uniform airflow velocity profile within the duct.
For testing adaptors, measuring ducts of varying diameter are available
These measuring ducts of varying diameter, reducing or enlarging, are made of stainless steel with the smoothest possible finish and have a transition angle α = 10° (2 × 5°)
The air transport through the ducts is set to an accuracy of ± 2,5 % The pressure differential is measured to an accuracy of ± 0,2 Pa
All tests shall be carried out with air at a temperature of the test environment
The coefficient of flow resistance of a fitting is determined from the difference between the static pressures in the two measuring ducts
Testing takes place at a nominal flow rate equivalent to a nominal velocity of 6 m/s in the fitting to be tested
First determine the friction of the measuring duct between the pressure measuring points without the pipe section or fitting to be tested There are two possible situations:
there are two measuring ducts of the same diameter;
there are two measuring ducts of different diameter because a reducing or enlarging adapter should be tested
In the latter case, a reducing or enlarging measuring duct (see 12.3.4.2) should be placed between the two measuring ducts referred to above
To test the section or fitting, first mount it in the rig after removing any attached reducing or enlarging measuring ducts Next, assess the friction of the measuring ducts between the pressure measuring points once more The friction of the section or fitting is calculated by taking the difference between the two test results.
NOTE The friction of the reducing or enlarging measuring ducts is thus ignored
12.3.4.4 Calculation of the friction value
The friction value may be calculated from the friction measured according to 12.3.4.3 by means of the following equation: w
1 ρ ζ ∆ (24) where ζ is the friction factor;
∆p is the measured friction, in Pascals; ρ is the density of air at the test conditions; wn is the nominal velocity, in meters per second
NOTE In the case of adapters, wn is related to the smaller diameter.
Vapour and condensate resistance test
A test apparatus which allows to deliver water vapour saturated air at a temperature of 52 °C ± 2 °C and a velocity of 1 m/s ± 0,2 m/s, consisting of a fan, a heater, a vapour steam vessel, and a flow rectifier (see Figure 11)
for flue gas temperature with an accuracy of ± 1,5 °C,
for layer temperature with an accuracy of ± 0,5 °C and
for humidity with an accuracy of ± 2 % in the range of 0 % to 80 % and of ± 3 % in the range of
The balance used for weighing test sample components must have an accuracy of ± 1 g for weights up to 10 kg and ± 2 g for weights exceeding 10 kg Additionally, it should be capable of weighing a minimum of two flue liners or two sections of air/flue configurations.
For measurement of air/flue configuration draught use a device with an accuracy of ± 1 Pa
For measurement of flue gas velocity use a device with an accuracy of ± 0,1 m/s
M measuring points at cross sections
Figure 11 — Water vapour diffusion test
The test sample for thermal performance tests must consist of the air/flue configuration, thermally conditioned as outlined in Table 3, and assembled according to Figure 11 Additionally, any openings claimed by the manufacturer must be installed in Zone C, as indicated in Figure 5.
Zone B shall have no enclosure
Measure and record the temperatures and relative humidity of:
the specified layers of the test sample and
Measure and record any change in weight
12.3.5.3.2 Ambient air temperature and humidity
Ambient air temperature, see 12.3.1.1.5.1 Ambient humidity shall be measured at the same position
12.3.5.3.3 Flue gas temperature and humidity
Measure the flue gas temperature with an accuracy of ± 1.5 K at a distance of (50 ± 2) mm before the inlet to the test air/flue configuration and at a position 500 mm below the exit at the top of the test sample Additionally, measure the flue gas humidity at these same positions.
Where a change in weight in components of the test sample is the assessment criteria specified in the specific product standard, measure the specified outer surface temperatures (see 12.3.1.1.5.3)
Where a change in humidity in components of the test sample is the assessment criteria specified in the specific product standard, measure:
the specified temperatures in the insulation layer and the outer surface temperature at the heights given in Figure 11;
the temperatures of the ventilating air at the inlet and outlet of the test air/flue configuration, where appropriate
Measure the temperatures to an accuracy of ± 0,3 K
To assess changes in humidity in test sample components as specified by the product standard, measure the relative humidity at the same relevant positions as the temperatures Ensure accuracy of ± 2 % RH for the range of 0 % RH to 80 % RH, and ± 3 % RH for the range of 80 % RH to 100 % RH (refer to Figure 11).
To assess the change in weight of test sample components as specified by the product standard, measure the weight increase before and after exposure to water vapor-saturated air.
12.3.5.3.7 Location for surface temperature and humidity / temperature measurements
Locations for surface temperatures and humidity / temperature measurements, at heights of 1 m, 2 m and 3 m are given in Figure 11.
Condensate resistance test
The test apparatus, as illustrated in Figure 12, is designed to spray colored water into the flue It comprises a tank, a water heater, a gate valve, an air supply (if necessary), a peristaltic pump, and spray equipment that ensures an even distribution of the spray.
The balance used for weighing test sample components must have an accuracy of ± 1 g for weights up to 10 kg and ± 2 g for weights exceeding 10 kg Additionally, it should be capable of weighing a minimum of two flue liners or two sections of air/flue configurations.
Figure 12 — Condensate resistance – test air/flue configuration
The test sample must include at least two sections or fittings, with a minimum of one joint When using the test air/flue configuration for the thermal performance test, only the two upper sections should be weighed.
the spray temperature and the spray volume;
the appearance of water on the outside the test sample of fittings or air/flue configuration sections of the test air/flue configuration;
the change in weight of the test sample
Dry and weigh the test sample used before spraying water
Spray (coloured) water on the inner surface at the outlet of the flue liner:
with a pressure of a maximum of 3 bar;
with a water volume related to the diameter (at 0,040⋅m 3 ⋅h -1 ⋅m -1 ± 0,008 m 3 ⋅h -1 ⋅m -1 ) during 4 h or until water appears on the outside of the test sample
Dry and weigh the test samples When components of the test air/flue configuration are weighed, they have to be dried and then re-weighed
the spray temperature and the spray volume;
the detection of (coloured) water outside of fittings or air/flue configuration sections;
the change in weight of the test sample after spraying water in comparison to the dried sample
the location of any appearance of water on the outside of any fitting or air/flue configuration section of the test samples and
any change in weight of the test sample or components.