ISO/DIS 5222-1:2025(en)

ISO/TC 86/SC 6

Secretariat: JISC

Second edition

2025-12-16

Heat recovery ventilators and energy recovery ventilators — Testing and calculating methods for seasonal performance factor —

Part 1:
Sensible heating recovery seasonal performance factors of heat recovery ventilators (HRVs)

Ventilateurs récupérateurs de chaleur et ventilateurs récupérateurs d'énergie — Méthodes d'essai et de calcul des facteurs de performances saisonnières —

Partie 1: Facteurs de performances saisonnières de la récupération de chaleur sensible des ventilateurs récupérateurs de chaleur (HRVs)

© ISO 2025

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Contents

Foreword v

Part 1: Sensible heating recovery seasonal performance factors of heat recovery ventilators (HRVs) 1

1 Scope 1

2 Normative references 1

3 Terms and definitions 1

4 Symbols and abbreviated terms 2

5 Tests 3

5.1 General requirements 3

5.2 Test conditions 3

5.3 Test methods 4

5.3.1 General 4

5.3.2 Energy saving stage limit temperature 4

5.3.3 Sensible heating recovery performance test 4

5.3.4 Determination of bypass outdoor temperature 4

5.3.5 Measurement of power input of heat recovery ventilator with bypass ventilation function 4

5.3.6 Determination of the frosting temperature by test 5

6 Calculations 6

6.1 Gross sensible heating recovery effectiveness (ε_sh) 6

6.2 Calculation of seasonal performance factor of sensible heating recovery (F_sh) 6

6.2.1 Reference outdoor air heating load and sensible heating recovery capacity 6

6.2.2 The characteristics of sensible heating recovery capacity against outdoor temperature 7

6.2.3 Power input characteristics of sensible heating recovery against outdoor temperature 8

6.2.4 Outdoor temperature bin distribution for heating 8

6.2.5 Calculation of seasonal sensible heating recovery capacity (E_sh) 9

6.2.6 Calculation of seasonal sensible heating recovery power input (P_in,E) 9

6.2.7 Calculation of seasonal performance factor for sensible heating recovery (F_sh) 9

7 Test report 9

Annex A (informative) The schematic diagram of HRVs’ heating (H) operation 11

Annex B (informative) The default outdoor temperature bin distribution for heating 13

B.1 Sample climate bins 13

B.2 Heating 13

Annex C (normative) Method of determination of the temperature T_F,0 14

Annex D (informative) Calculating method for seasonal performance factor when setting a specific application heating load 15

D.1 General 15

D.2 Application outdoor air temperature BIN 15

D.3 Set of specific application condition of HRVs 15

D.4 Calculation of the sensible heating performance factor of HRVs 15

Annex E (normative) Calculation of the bypass outdoor temperature 17

Annex F (informative) Report template 18

F.1 General 18

F.2 Essential information and rating performance 18

F.3 Sensible heating recovery seasonal performance factors of HRVs 18

Bibliography 21

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISO's adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 86, Refrigeration and air-conditioning, Subcommittee SC 6, Testing and rating of air-conditioners and heat pumps.

A list of all parts in the ISO 5222 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.This second edition cancels and replaces the first edition (ISO 5222-1:2023), which has been technically revised. The main changes are as follows:

— Terms and definitions are revised to correspond with Part 2 and Part 3 of the ISO 5222 series.

— Symbols are revised in accordance with ISO/IEC Directives, Part2.

— Names of stages are revised to correspond with Part 2 and Part 3 of the ISO 5222 series.

— 6.2 Sensible heating coefficient of energy and 3.3 coefficient of energy is deleted.

— Errors in 6.2.3 are corrected.

— A note has been added in 6.2.5 for clarification.

— Figure A.1 has been revised to correspond with Part 2 and Part 3 of the ISO 5222 series.

Heat recovery ventilators and energy recovery ventilators — Testing and calculating methods for seasonal performance factor —
Part 1:
Sensible heating recovery seasonal performance factors of heat recovery ventilators (HRVs)

This document specifies the testing and calculating methods for sensible heating recovery seasonal performance factor of heat recovery ventilators (HRVs) covered by ISO 16494-1:2022.

This document also specifies the test conditions and the corresponding test procedures for determining the sensible heating recovery seasonal performance factor of HRVs and is intended for use only in marking, comparison, and certification purposes.

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 16494‑1:2022, Heat recovery ventilators and energy recovery ventilators — Method of test for performance — Part 1: Development of metrics for evaluation of energy related performance

ISO 16494‑1:2022/Amd 1:2023, Heat recovery ventilators and energy recovery ventilators — Method of test for performance — Part 1: Development of metrics for evaluation of energy related performance

ISO 16358‑2:2013, Air-cooled air conditioners and air-to-air heat pumps — Testing and calculating methods for seasonal performance factors — Part 2: Heating seasonal performance factor

ISO 16358‑2:2013/Cor 1:2013, Air-cooled air conditioners and air-to-air heat pumps — Testing and calculating methods for seasonal performance factors — Part 2: Heating seasonal performance factor—Technical corrigendum 1

For the purposes of this document, the terms and definitions given in ISO 16494-1:2022 and the following apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https://www.iso.org/obp

— IEC Electropedia: available at https://www.electropedia.org/

3.1

heat recovery

<sensible heating> transfer of sensible energy from exhaust air to supply air in HRVs while heating

3.2

bypass ventilation function

function for reducing power input of the fans while the heat energy recovered is less than the additional energy input due to overcoming the resistance of recovery heat exchanger during its operation time

Note 1 to entry: The bypass ventilation function makes the supply air and/or exhaust air go through the bypass passage with energy saving control.

3.3

gross effectiveness

<sensible heating> measured effectiveness, not adjusted for leakage, motor heat gain, or heat transfer through the unit casing

Note 1 to entry: The sensible heating gross effectiveness of HRVs, at equal airflow, is described in ISO 16494-1:2022, 9.5.

3.4

bypass outdoor temperature

T_b

outdoor temperature in heating conditions, at which the power reduction to HRVs by operating in bypass mode is equal to the saving of power input to the heating system due to the heat recovered by HRVs

3.5

seasonal performance factor of sensible heating recovery

F_sh

ratio of seasonal amount of sensible heat recovered together with power value of moving air to the whole power input of HRVs, under the rating conditions and seasonal outdoor temperature bins selected from this standard

3.6

building heating balance temperature

T_BHB

outdoor air temperature at which building internal heat gain, solar radiation, and so on, equals to heat loss through the building envelope

The test conditions used, the accuracy and uncertainties of the instruments used shall conform with ISO 16494-1:2022 and those in this document.

For the purpose of ε_sh, E_sh and F_sh, there are three standard test conditions T5/T6/T7 corresponding to ISO 16494-1:2022, Table 2. HRVs shall be tested at one of the three test conditions, which shall be selected to most closely represent the outdoor temperature bin distribution in the region as described in Annex B and Annex D.

Outdoor temperature bin distribution and bin hours differ from region to region. If bin hours are set to a certain value for a certain region, the integrated value of heating load and energy consumption can be determined.

Table 1 shows the requirement of default values and the reference outdoor temperature bin distribution for test and calculation. In case of setting other outdoor temperature bin distribution, refer to the setting method as described in Annex D.

Table 1 — Conditions of performance test (heating)

For higher seasonal energy performance, HRVs can be designed with airflow bypass function integrating fan speed control or airflow control devices, which can change the fan power input according to different outdoor temperature condition, while keeping necessary aerodynamic performance.

To assess the energy saving ability of HRVs, the operation stages under the application temperature bin are shown in Annex A using a schematic diagram.

Standard condition performance tests

The sensible heating recovery performance tests shall be conducted in accordance with ISO 16494-1:2022. The sensible heating recovery performance, efficiency, as well as airflow and static pressure shall be measured corresponding to the selected standard heating performance tests conditions in Table 1.

Determination of performance at application climate

The sensible heating recovery performance under certain climate temperature bins shall also be determined by calculation using the temperature bins see Annex B and Annex D.

The manufacturer shall specify the value of bypass outdoor temperature. The laboratory shall verify that the unit under test is functioning and what the test action temperature is. If it is not specified by the manufacturer, the laboratory shall calculate the outdoor bypass temperature and set it as the T_b in accordance with Annex E.

5.3.5.1 The manufacturer can provide information on how to set the bypass function if requested by the testing laboratories.

NOTE 1 Due to the additional air resistance of the heat recovery exchanger, when the heat energy recovered is less than the additional energy input due to overcoming the resistance of recovery heat exchanger during its operation time, the equipment can provide the bypass ventilation function to reduce the additional energy consumption, when only ventilation is necessary.

NOTE 2 When the bypass ventilation function acts, there can be several means to reduce the additional energy consumption (e.g. with fan speed control or valve control in the fan’s inlet or outlet, etc., to keep the same airflow rate and pressure as rating performance condition).

5.3.5.2 The tests shall be conducted at the required control set which allows steady state operation of the equipment at the given test conditions.

5.3.5.3 Test of unit with bypass ventilation function and fan speed control shall be as follows:

a) Set up the bypass ventilation function according to the manufacturer's instructions.

b) Adjust test auxiliary device to keep the average pressure value at air outlet and inlet of unit in Figure A.1 of ISO 16494-1:2022, within the 5 % of tested unit’s nominal value, the airflow rate larger or equal to its nominal value.

c) According to ISO 16494-1:2022, measure and record the data of airflow rate, the pressure and power input.

d) Determine and record the outdoor temperature at which the bypass ventilation function acts, either by manufacturer's statement, or by measure. The power input value measured when bypass ventilation functions is activated is recorded as the bypass ventilation function power input, used for calculation for F_sh corresponding to each outdoor bin temperature in ventilation period.

5.3.5.4 Test of unit with bypass ventilation function and airflow control devices, but without fan speed control shall be as follows:

a) Set up the bypass ventilation function according to the manufacturer's instructions.

b) Adjust the test auxiliary device to keep the average pressure value within the 5 % of the tested unit’s nominal value, the airflow rate larger or equal to its nominal value.

c) Determine and record the outdoor temperature at which the bypass ventilation function acts, either by the manufacturer's statement, or by measurement. The power input value measured when bypass ventilation function is on shall be recorded as the bypass ventilation function power input, used for the calculation of F_sh corresponding to each outdoor bin temperature in the ventilation period.

5.3.5.5 Test of equipment with bypass ventilation function and without fan speed control and without automatic airflow control devices shall be as follows:

a) Set up the bypass ventilation function according to manufacturer’s instruction.

b) According to ISO 16494-1:2022, do not adjust any of the test auxiliary devices during test and record the data of airflow rate, the pressure and power input.

c) Determine and record the outdoor temperature that the bypass ventilation function acts, either by the manufacturer's statement, or by test.

d) The power input value measured when bypass ventilation functions on is recorded as the bypass ventilation function power input, used for calculation for F_sh corresponding to each outdoor bin temperature in ventilation period.

5.3.5.6 Test of equipment with no bypass ventilation function shall be as follows:

For the equipment with no bypass ventilation function, the power input is the value as same as in 5.3.3.1 all stages, which shall be used for calculation for F_sh corresponding to each outdoor temperature in ventilation period.

5.3.6.1 The frost temperature test shall be conducted in accordance with ISO 16494-1:2022. The manufacturer can provide information on how to operate the equipment if requested by the testing laboratories.

5.3.6.2 The test condition shall be as follows:

a) The airflow rate and static pressure shall keep the same as 5.3.3.1.

b) The entering exhaust air (RA) temperature shall be kept at conditions T5/T6/T7 specified in Table 1 and entering supply air (OA) temperature shall be gradually reduced from 0 °C, or, in order to reduce the duration time of the test, from the T_F,0, which is described in Annex C, plus 2 K.

NOTE The calculation of T_F,0 refers to Annex C.

5.3.6.3 Confirmation of frost outdoor air temperature shall be as follows:

a) Turn off the supplement heat function for anti-frost.

b) Conduct the tests of gross sensible heating recovery effectiveness of HRVs by changing outdoor temperature from the T_F,0 plus 2 K to lower temperature. While adjusting the outdoor air temperature, keep the reducing rate of temperature not less than 0,5 K per hour and not greater than 1,0 K per hour.

c) Record the inlet and outlet air parameters so that gross sensible heating effectiveness can be calculated every 0,5 h.

d) Calculate the gross sensible heat effectiveness in accordance with ISO 16494-1:2022, 9.5.

e) If the absolute value of the change of the gross sensible heating effectiveness between the outdoor temperature t_j and temperature t_j-1 is greater than 5 %, the higher temperature of the outdoor temperatures is confirmed as T_F.

f) Compare the tested T_F with the one in practice, if the tested T_F is lower than the one in practice, select the temperature in practice as the stage limitation temperature, otherwise, the tested T_F shall be the stage limitation temperature.

5.3.6.4 Data collection shall be as follows:

During the frost temperature tests, airflow rate, static pressure, barometer pressure and power input as well as air temperature shall be collected and recorded. A continuous air temperature variation curve drawing shall be necessary.

The gross sensible heating recovery effectiveness of HRVs at rated test condition is described in ISO 16494-1:2022, 9.5.

The reference outdoor air heating load shall be by a set of values and be assumed that they are linearly changing depending on the change of outdoor temperature, the sensible heat recovery capacity is assumed also linearly changing, see figure in Annex A. Conditions of reference heating load and recovery capacity is shown in Table 2.

Table 2 — Reference outdoor air sensible heating load and recovery capacity

The outdoor air sensible heating load L_sh,t,j at outdoor temperature t_j, which is necessary to calculate the seasonal sensible heating heat recovery, shall be determined by Formula (1)

(1)

where

Sensible heating recovery capacity ϕ_sh,t,j (W) of HRVs at outdoor temperature t_j changes depending on outdoor temperatures, as shown in Figure A.1 in Annex A, and it is determined by Formulae (2) and (3).

The stages are described in Annex A.

a) H,Stage 1 ventilation with or without bypass function at heat recovery mode

For HRVs with bypass function, recovery capacity ϕ_sh,t,j at outdoor temperature t_j shall be zero.

For HRVs without bypass function, recovery capacity ϕ_sh,t,j at outdoor temperature t_j shall be determined by Formula (2)

(2)

where

NOTE H,Stage 1 may or may not exist depending on the manufacturer’s product or system.

b) H,Stage 2 ventilation at heat recovery mode

In case of T_F < t_j ≤ T_b, recovery capacity ϕ_sh,t,j at outdoor temperature t_j shall be determined by Formula (2).

c) H,Stage 3 ventilation with supplement heat at heat recovery mode

In case of t_j ≤ T_F, recovery capacity ϕ_sh,t,j at outdoor temperature t_j shall be determined by Formula (3)

(3)

where

Power input P_in,t,j (W) of HRVs at outdoor temperature t_j changes with outdoor temperatures and corresponding operation functions as shown in Figure A.1 in Annex A, and it is determined as follows:

a) H,Stage 1 ventilation with or without bypass function at heat recovery mode

Power input P_in,t,j to ventilator at outdoor temperature t_j shall be determined by the measured value P_in,by,t,j with bypass or the measured value P_in,no,t,j without bypass function.

b) H,Stage 2 ventilation at heat recovery mode

Power input P_in,t,j to ventilator at outdoor temperature t_j shall be determined by the measured value P_in,no,t,j without bypass function.

c) H,Stage 3 ventilation in heat recovery mode with supplemental pre-heat

Power input P_in,t,j at outdoor temperature t_j, shall be determined by Formula (4), with ideal proportional preheat control:

(4)

where

Power input P_in,t,j at outdoor temperature t_j, shall be determined by Formula (5), with simple preheat control:

(5)

where

Value of outdoor temperature and bin hours differ from region to region. If bin-hours set to a certain value for a certain region, the value of heating load and energy consumption can be determined.

Annex B shows the reference outdoor temperature bin distribution for heating.

In case of setting other outdoor temperature bin distribution, refer to the setting method as described in Annex D.

Seasonal sensible heating recovery capacity (E_sh) shall be determine using Formula (6) from the total sum of sensible heating recovery at each outdoor temperature t_j.

(6)

where

NOTE  In case of unducted units, P_vma,t,j =0. The formula for P_vma,t,j is defined in ISO 16494-1:2022, 9.6.1.

Seasonal sensible heating recovery power input, P_in,E, shall be determined using Formula (7) from the total sum of seasonal sensible heating power input at each outdoor temperature t_j.

(7)

where

Sensible heating recovery seasonal performance factor (F_sh) shall be determined using Formula (8):

(8)

where

The test report shall include:

a) the simple description of sample;

b) the International Standard used (including its year of publication);

c) the results which include at least the following:

— the list of mandatory test points performed,

— gross sensible heating effectiveness and seasonal sensible heating performance factor (F_sh) values under corresponding rating condition,

— the list of optional test points performed,

— gross sensible heating effectiveness and seasonal sensible heating performance factor (F_sh) values of the optional test points,

— the default values used,

— the assumed default value of heating coefficient of performance of air conditioner or refrigeration system.

d) the deviations from the procedure;

e) the unusual features observed;

f) the date of the test.

The heating seasonal performance factor (F_sh) shall be declared with three significant digits, with reference to the reference defined heating load and to the reference outdoor temperature bin distribution used.

NOTE Refer to Annex F for a template of the additional data to be collected and calculated results.

1. 
   (informative)
   
   The schematic diagram of HRVs’ heating (H) operation

For HRVs with energy saving function, the operation stages under the application temperature bins are as below, which are also explained in Figure A.1 using a schematic diagram.

a) V,Stage, when the outdoor air temperature changes from a higher temperature T_0,h equals to that defined in ISO 16494-1:2022, Table 2 as T5/T6/T7 to T_BHB (here 16 °C, which is the reference value in ISO 16358-2;2013, as an example), the outdoor air heating load is assumed zero due to the air conditioner off, which means heating not needed and recovery not desirable in V,Stage of Figure A.1. For ventilation, the fans will continue running and the power input of fans will vary with or without ventilation bypass function in HRVs.

NOTE 1 The building heating balance temperature means when the outdoor air temperature is lower than it, the room space should provide heating for comfortable indoor environment. It can be different from country and region according to energy saving code. Here and in Annex B, 16 °C is assumed as building heating balance temperature.

b) H,Stage 1, when the outdoor air temperature changes from T_BHB to T_b, the outdoor air heating load will increase, but the power consumption of fans for overcoming the additional air resistance of heat recovery exchanger itself is larger than the equivalent power consumption calculated by using heat recovery amount to converting into. For energy saving, the supplying and exhausting airflow through heat recovery exchanger can go through with bypass function, consequently the power input of fans for ventilation can be different from the units with or without ventilation bypass function.

NOTE 2 The temperature T_b for HRVs with bypass function can be confirmed in laboratory when the energy saving control function is activated. For HRVs without bypass function, the T_b does not exist.

c) H,Stage 2, when the outdoor air temperature changing from T_b to T_F, the outdoor air heating load will continue to increase with the outdoor temperature decreasing, at this stage the bypass function of ventilation should be closed. The power input of fans for ventilation is constant to HRVs with or without bypass function, due to bypass function closed.

NOTE 3 The lower the T_F, the better the seasonal energy saving performance. It needs to optimize the design of HRVs to keep the temperature difference between heat transfer surfaces of heat exchanger uniform, and also needs to optimize the type selection of heat exchanger, for example, when using the heat exchanger with the ability of latent transfer to sensible heating recovery purpose, the T_F can be even lower than the sensible transfer only type.

d) H,Stage 3, when the outdoor air temperature changing from T_F to a lower temperature, the outdoor air heating load will increase with the outdoor temperature decrease, but the wet air frosting on the surface of heat recovery exchanger will weaken the recovery capacity. For keeping up the recovery ability, it is needed to input supplement heat to defrosting the exchanger surface. From T_F to a lower temperature, the heat recovery capacity will be the same, but the supplement power input will increase gradually, or a higher constant value which determined by keeping no frost in whole range of operation, correspondingly the total power input will also increase.

NOTE 4 In this document, assuming the supplement heating for F_sh calculation is provided through electricity.

NOTE 5 The methods for determine the temperature T_F see Annex C.

Figure A.1 — Operation stages for HRVs

1. 
   (informative)
   
   The default outdoor temperature bin distribution for heating
   1. Sample climate bins

The bin limit temperature of T_BHB equals 16 °C, which is the reference value in ISO 16358-2;2013, for all types of climate when heating.

• 1. Heating

Table B.1 shows the default outdoor temperature bin distribution. Table B.2 shows the default hours for calculation of seasonal performance factor for sensible heating recovery.

NOTE The calculation of heating seasonal performance factor can also be undertaken for other temperature bin distributions as shown in Annex D.

Table B.1 — The default outdoor temperature bin distribution for heating

Table B.2 — Default hours for the calculation of seasonal performance factor for sensible heating recovery

1. 
   (normative)
   
   Method of determination of the temperature T_F,0

The test for the determination of temperature T_F is provided in 5.3.6. The outdoor air temperature shall be gradually reduced from 0 °C, or, to save time, from a lower temperature T_F,0. This temperature is intended to be lower than 0 °C but above the actual T_F. The temperature T_F,0 shall not be used as T_F, which shall be determined by test. The temperature T_F,0 can be predicted as shown in Formula (C.1):

(C.1)

where

1. 
   (informative)
   
   Calculating method for seasonal performance factor when setting a specific application heating load
   1. General

Under application condition, the outdoor air heating load and the operating strategy of air conditioners and heat pumps, as well as HRVs, widely varies from region to region globally.

In order to evaluate and compare the seasonal performance factor among HRVs, it is desirable to establish the method used in application condition and different operating strategy.

For this purpose, this annex provides steps and method.

• 1. Application outdoor air temperature BIN

Refer to the reference climate data of application location using HRVs, statistics and classification work shall be done and the table of outdoor climate bin hours shall be finished like used in Annex B.

• 1. Set of specific application condition of HRVs

D.3.1 The temperature at which air conditioners and heat pumps are put into active mode shall be specified.

D.3.2 The indoor thermal comfortable temperature shall be set as the initial temperature for existing outdoor air heating load.

D.3.3 Test of the gross sensible heating recovery effectiveness under the indoor air temperature as D.3.2 while the outdoor air temperature shall be the same as in Table 1.

• 1. Calculation of the sensible heating performance factor of HRVs

Under the redefined conditions provided above, the calculation of seasonal performance factor for sensible heating recovery (F_sh) is made in accordance with the provisions specified in the main standard body.

Table D.1 shows the sample template for outdoor temperature bin distribution. Table D.2 shows the sample template for the calculation of seasonal performance factor for sensible heating recovery.

Table D.1 — Sample template of outdoor temperature bin distribution for heating

Table D.2 — Sample template of default hours for the calculation of seasonal performance factor for sensible heating recovery

1. 
   (normative)
   
   Calculation of the bypass outdoor temperature

The outdoor temperature T_b influences the F_sh rating of unit. Higher values of T_b results in improved seasonal energy saving performance.

NOTE Manufacturers can optimize the selections and design of HRVs by enhancing the efficiency of fans and motors as well as the effectiveness of heat recovery exchangers, also decreasing resistance of the airflow channels and selecting better speed control device of fans.

For HRVs without bypass function, there is no T_b.

For HRVs with bypass function, the T_b shall be calculated using Formula (E.1):

(E.1)

where

1. 
   (informative)
   
   Report template
   1. General

This annex describes an example of data collection and reporting sheet. Clause F.2 focuses on the essential information and rating performance according to ISO 16494-1:2022. Table F.1 indicates the data collection and reporting sheet based on ISO 16494-1:2022 and above standard body.

• 1. Essential information and rating performance

F.2.1 For airflow measurement data to be collected and calculated results should be consistent with Annex E in ISO 16494-1:2022, data to be collected and calculated results for airflow measurement per Annex A in ISO 16494-1;2022.

F.2.2 For net supply airflow measurement by decay method, data to be collected and calculated results should be consistent with Annex E in ISO 16494-1:2022, data to be collected and calculated results for net supply airflow measurement by decay method per Annex B in ISO 16494-1;2022.

F.2.3 For UEATR measurement, data to be collected and calculated results should be consistent with Annex E in ISO 16494-1:2022, data to be collected and calculated results for UEATR measurement per Annex C in ISO 16494-1;2022.

F.2.4 For effectiveness measurement, data to be collected and calculated results should be consistent with Annex E in ISO 16494-1:2022, data to be collected and calculated results for effectiveness measurement per Annex D in ISO 16494-1;2022.

F.2.5 For COE, EW and Net supply airflow, data to be collected and calculated results should be consistent with Annex E in ISO 16494-1;2022, data to be collected and calculated results for COE, EW and Net supply airflow.

• 1. Sensible heating recovery seasonal performance factors of HRVs

Table F.1 — Data to be collected and calculated results for sensible heating recovery seasonal performance factors of HRVs

Bibliography

[1] ISO/TR 16494‑2:2019, Heat recovery ventilators and energy recovery ventilators — Method of test for performance — Part 2: Assessment of measurement uncertainty of performance parameters