Gas-fired endothermic engine driven heat pumps - Part 5: Calculation of seasonal performances in heating and cooling mode

This part of the FprEN 16905 series specifies the calculation of seasonal performance factor for gas-fired endothermic engine driven heat pumps for heating and/or cooling mode including the engine heat recovery.

Gasbefeuerte endothermische Motor-Wärmepumpen - Teil 5: Berechnung der saisonalen Effizienzkennzahlen im Heiz- und Kühlmodus

Dieser Teil von EN 16905 legt die Berechnung des saisonalen Leistungsfaktors von gasbefeuerten endothermischen Motor-Wärmepumpen, die für den Heiz- und/oder Kühlbetrieb vorgesehen sind, einschließlich der Außen-Motor-Wärmerückgewinnung, fest.
Dieses Dokument gilt ausschließlich für Geräte mit einer maximalen Wärmebelastung von 70 kW (bezogen auf den Heizwert [NCV; en: net calorific value]) bei Norm-Nennbedingungen.
Dieses Dokument gilt ausschließlich für Geräte der Kategorien I2H, I2E, I2Er, I2R, I2E(S)B, I2L, I2LL, I2ELL, I2E(R)B, I2ESi, I2E(R), I3P, I3B, I3B/P, II2H3+, II2Er3+, II2H3B/P, II2L3B/P, II2E3B/P, II2ELL3B/P, II2L3P, II2H3P, II2E3P und II2Er3P nach EN 437:2021.
Dieses Dokument gilt ausschließlich für Geräte mit:
a)   endothermischen Gasmotoren, die durch vollständig automatisierte Regelungen gesteuert werden;
b)   geschlossenen Kühlkreislaufsystemen, in denen das Kühlmittel nicht direkt mit der zu kühlenden oder zu erwärmenden Flüssigkeit in Berührung kommt;
c)   einer Temperatur des Wärmeübertragungsmediums im Heizsystem (Heizungswasserkreislauf), die im Normalbetrieb 105 °C nicht überschreitet;
d)   einem höchsten Betriebsdruck im:
1)   Heizungswasserkreislauf (falls installiert), der 6 bar nicht überschreitet,
2)   Warmwasserbereitungskreislauf für Nutzwasser (falls installiert), der 10 bar nicht überschreitet.
Dieses Dokument gilt ausschließlich für GEHP-Geräte, die zur Raumheizung oder -kühlung oder zur Kälteerzeugung mit oder ohne Wärmerückgewinnung angewendet werden.
Dieses Dokument ist anwendbar für GEHP-Geräte, die einer Typprüfung zu unterziehen sind. Anforderungen an nicht typgeprüfte GEHP-Geräte müssten einer näheren Betrachtung unterzogen werden.

Pompes à chaleur à moteur endothermique alimenté au gaz -Partie 5 : Calcul des performances saisonnières en modes chauffage et refroidissement

La présente partie de l'EN 16905 décrit le calcul du facteur de performance saisonnière des pompes à chaleur à moteur endothermique alimenté au gaz pour le mode chauffage et/ou refroidissement, y compris la récupération de chaleur du moteur, qui doivent être utilisées en extérieur.
Le présent document ne s'applique qu'aux appareils dont le débit calorifique maximal (dérivé du pouvoir calorifique inférieur) ne dépasse pas 70 kW dans les conditions de performance nominale.
Le présent document se limite également aux appareils classés dans les catégories I2H, I2E, I2Er, I2R, I2E(S)B, I2L, I2LL, I2ELL, I2E(R)B, I2ESi, I2E(R), I3P, I3B, I3B/P, II2H3+, II2Er3+, II2H3B/P, II2L3B/P, II2E3B/P, II2ELL3B/P, II2L3P, II2H3P, II2E3P et II2Er3P de l'EN 437:2021.
Le présent document ne s'applique qu'aux appareils :
a)   équipés de moteurs endothermiques alimentés au gaz régulés par des systèmes de régulation entièrement automatisés ;
b)      comportant des circuits fermés de réfrigérant dans lesquels le réfrigérant n'entre pas en contact direct avec le fluide à refroidir ou à chauffer ;
c)   dans lesquels la température du fluide caloporteur du système de chauffage (circuit d'eau de chauffage) ne dépasse pas 105 °C dans les conditions normales de fonctionnement ;
d)   dans lesquels la pression maximale de fonctionnement :
1)   ne dépasse pas 6 bar dans le circuit d'eau de chauffage (le cas échéant) ; et
2)   ne dépasse pas 10 bar dans le circuit d'eau chaude sanitaire (le cas échéant).
Le présent document s'applique aux appareils GEHP utilisés uniquement pour le chauffage de locaux, le refroidissement de locaux ou la réfrigération, avec ou sans récupération de chaleur.
Le présent document s'applique aux appareils GEHP destinés à être soumis à des essais de type. Les exigences relatives aux appareils GEHP non soumis à des essais de type pourraient être assujetties à des considérations supplémentaires.

Toplotna črpalka s plinsko gnanim motorjem z notranjim zgorevanjem - 5. del: Izračun sezonske zmogljivosti za ogrevanje in hlajenje

Ta del iz skupine standardov FprEN 16905 določa metode za izračun faktorja sezonske zmogljivosti za toplotne črpalke s plinsko gnanim motorjem z notranjim zgorevanjem za ogrevanje in/ali hlajenje, vključno z rekuperacijo toplote motorja.

General Information

Status
Published
Public Enquiry End Date
02-Jan-2022
Publication Date
12-Feb-2023
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
09-Feb-2023
Due Date
16-Apr-2023
Completion Date
13-Feb-2023

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 16905-5:2023
01-marec-2023
Nadomešča:
SIST EN 16905-5:2018
Toplotna črpalka s plinsko gnanim motorjem z notranjim zgorevanjem - 5. del:
Izračun sezonske zmogljivosti za ogrevanje in hlajenje
Gas-fired endothermic engine driven heat pumps - Part 5: Calculation of seasonal
performances in heating and cooling mode
Gasbefeuerte endothermische Motor-Wärmepumpen - Teil 5: Berechnung der
saisonalen Effizienzkennzahlen im Heiz- und Kühlmodus
Pompes à chaleur à moteur endothermique alimenté au gaz -Partie 5 : Calcul des
performances saisonnières en modes chauffage et refroidissement
Ta slovenski standard je istoveten z: EN 16905-5:2022
ICS:
27.080 Toplotne črpalke Heat pumps
SIST EN 16905-5:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 16905-5:2023

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SIST EN 16905-5:2023


EN 16905-5
EUROPEAN STANDARD

NORME EUROPÉENNE

December 2022
EUROPÄISCHE NORM
ICS 27.080 Supersedes EN 16905-5:2017
English Version

Gas-fired endothermic engine driven heat pumps - Part 5:
Calculation of seasonal performances in heating and
cooling mode
Pompes à chaleur à moteur endothermique alimenté Gasbefeuerte endothermische Motor-Wärmepumpen -
au gaz -Partie 5 : Calcul des performances saisonnières Teil 5: Berechnung der saisonalen Effizienzkennzahlen
en modes chauffage et refroidissement im Heiz- und Kühlmodus
This European Standard was approved by CEN on 28 November 2022.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 16905-5:2022 E
worldwide for CEN national Members.

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SIST EN 16905-5:2023
EN 16905-5:2022 (E)
Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Part load conditions for space cooling . 7
4.1 General . 7
4.2 Air-to-air units . 7
4.3 Water-to-air and brine-to-air units . 8
4.4 Air-to-water and air-to-brine units . 8
4.5 Water-to-water and brine-to-water units . 9
5 Part load conditions for space heating . 11
5.1 General . 11
5.2 Air-to-air units . 11
5.3 Water(brine)-to-air units . 12
5.4 Air-to-water(brine) units . 12
5.4.1 General . 13
5.4.2 Low temperature application . 13
5.4.3 Intermediate temperature application . 14
5.4.4 Medium temperature application . 15
5.5 DX-to-water(brine), water-to-water(brine), brine-to-water(brine) units . 15
5.5.1 General . 15
5.5.2 Low temperature application . 16
5.5.3 Intermediate temperature application . 17
5.5.4 Medium temperature application . 18
6 Calculation methods for reference SPER . 19
c
6.1 General . 19
6.2 General formula for calculation of GUE and AEF . 19
c c
6.3 General formula for calculation of EHRE and AEHRF . 19
c c
6.4 General formula for calculation of reference SGUE . 19
c
6.5 Calculation of reference SEHRE . 20
c
6.6 Calculation of reference SGUE . 21
Tc
6.7 Calculation of reference SAEF . 21
c
6.8 Calculation of reference annual cooling demand (Q ) . 21
ref,c
6.9 Calculation of reference SAEF . 22
cON
6.10 Calculation of reference SAEHRF . 22
c
6.11 Calculation of reference total SAEF . 23
Tc
6.12 Procedures for the determination of GUE / AEF values . 23
cPL cPL
6.13 Procedures for the determination of EHRE / AEHRF values . 23
cPL cPL
6.14 Calculation of reference SPER . 23
c
6.15 Calculation of the annual primary energy consumption cooling Q . 24
CP
6.16 Calculation of the seasonal space cooling efficiency η . 24
s,c
7 Calculation methods for reference SPER . 24
h
7.1 General . 24
2

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SIST EN 16905-5:2023
EN 16905-5:2022 (E)
7.2 General formula for calculation of GUE and AEF . 25
h h
7.3 General formula for calculation of EHRE . 25
h
7.4 General formula for calculation of reference SGUE . 25
h
7.5 Calculation of reference SEHRE . 28
h
7.6 Calculation of reference SGUE . 28
Th
7.7 Calculation of reference SAEF . 28
h
7.8 Calculation of reference annual heating demand (Q ) . 29
ref,h
7.9 Calculation of reference SAEF . 29
hON
7.10 Calculation of reference SAEHRFh . 30
7.11 Calculation of reference total SAEF . 30
Th
7.12 Procedures for the determination of GUE / AEF values . 30
hPL hPL
7.13 Procedures for the determination of EHRE / AEHRF values . 30
hPL hPL
7.14 Calculation of reference SPER . 31
h
7.15 Calculation of the annual primary energy consumption heating Q . 31
HP
7.16 Calculation of the seasonal space heating efficiency η . 31
s,h
8 Technical documentation . 32
Annex A (normative) Determination of reference annual cooling/heating demands and
determination of hours for active mode, thermostat off, standby, off mode and
crankcase heater mode for reference SAEFc and SAEFh calculation . 33
Annex B (informative) Calculation example for reference SGUE , SAEF , SEHRE , SAEHRF ,
c c c c
SGUE , SAEF and SPER . 35
Tc Tc c
Annex C (informative) Calculation example for reference SGUE , SAEF , SEHRE , SAEHRF ,
h h h h
SGUE , SAEF and SPER . 38
Tc Th h
Annex D (informative) Template for technical documentation . 41
Annex E (normative) Rating of outdoor units of multi-split air conditioners and heat pumps . 46
Annex ZA (informative) Relationship between this European Standard and the
requirements of Commission Regulation (EU) No 813/2013 aimed to be covered . 49
Annex ZB (informative) Relationship between this European Standard and the
requirements of Commission Regulation (EU) No 2016/2281 aimed to be covered . 50
Annex ZC (informative) Relationship between this European Standard and the requirements
of Commission Regulation (EU) No 811/2013 aimed to be covered . 51
Bibliography . 52

3

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SIST EN 16905-5:2023
EN 16905-5:2022 (E)
European foreword
This document (EN 16905-5:2022) has been prepared by Technical Committee CEN/TC 299 “Gas-fired
sorption appliances, indirect fired sorption appliances, gas-fired endothermic engine heat pumps and
domestic gas-fired washing and drying appliances”, the secretariat of which is held by UNI.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by June 2023, and conflicting national standards shall be
withdrawn at the latest by June 2023.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 16905-5:2017.
EN 16905-5:2022 includes the following significant technical changes with respect to
EN 16905-5:2017:
— technical changes throughout the draft and in Annex ZA, Annex ZB and Annex ZC in order to align
the text with the Ecodesign Requirements stated in Commission Regulation (EU) No 2016/426.
This document has been prepared under a Standardization Request given to CEN by the European
Commission and the European Free Trade Association, and supports essential requirements of EU
Directive(s) / Regulation(s).
For relationship with EU Directive(s) / Regulation(s), see informative Annex ZA, Annex ZB and
Annex ZC, which are integral parts of this document.
EN 16905 comprises the following parts under the general title Gas‐fired endothermic engine driven heat
pumps:
— Part 1: Terms and definitions;
— Part 2: Safety;
— Part 3: Tests conditions;
— Part 4: Tests methods;
— Part 5: Calculation of seasonal performances in heating and cooling mode.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
4

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SIST EN 16905-5:2023
EN 16905-5:2022 (E)
Introduction
This document specifies the calculation of seasonal performances in heating and cooling mode of air
conditioners and heat pumps using either air, water or brine as heat transfer media, with gas-fired
endothermic engine driven compressors when used for space heating, cooling and refrigeration,
hereafter referred to as “GEHP appliance”.
Single split and multisplit systems are covered by this document.
The GEHP appliances can have one or more primary or secondary functions.
The GEHP appliances having their condenser cooled by air and by the evaporation of external additional
water are not covered by this document.
EN 16905-5:2022 has been prepared to address the essential requirements of the European Regulation
(EU) 2016/426 relating to appliances burning gaseous fuels and repealing Directive 2009/142/EC (see
1 2 1
EN 16905-4:— , Annex ZA). EN 16905-1:2017, EN 16905-2:— , EN 16905-3:2017, EN 16905-4:— and
EN 16905-5:2022 are linked to the Energy Related Products Directive (2009/125/EC) in terms of tests
conditions, tests methods and seasonal performances calculation methods under Mandate M/535; (see
1
EN 16905-3:2017, Annex ZA, EN 16905-4:— , Annex ZA, EN 16905-5:2022, Annex ZA and
2
EN 16905-2:— , Annexes ZB and ZC).
These documents will be reviewed whenever new mandates could apply.

1
Under preparation. Stage at the time of publication: prEN 16905-4:2022.
2
Under preparation. Stage at the time of publication: prEN 16905-2:2021.
5

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SIST EN 16905-5:2023
EN 16905-5:2022 (E)
1 Scope
This part of EN 16905 specifies the calculation of the seasonal performance factor for gas-fired
endothermic engine driven heat pumps for heating and/or cooling mode including the engine heat
recovery, to be used outdoors.
This document only applies to appliances with a maximum heat input (based on net calorific value) not
exceeding 70 kW at standard rating conditions.
This document only applies to appliances under categories I , I , I , I , I , I , I , I , I , I ,
2H 2E 2Er 2R 2E(S)B 2L 2LL 2ELL 2E(R)B 2ESi
I , I , I , I , II , II , II , II , II , II , II , II , II and II according to
2E(R) 3P 3B 3B/P 2H3+ 2Er3+ 2H3B/P 2L3B/P 2E3B/P 2ELL3B/P 2L3P 2H3P 2E3P 2Er3P
EN 437:2021.
This document only applies to appliances having:
a) gas fired endothermic engines under the control of fully automatic control systems;
b) closed system refrigerant circuits in which the refrigerant does not come into direct contact with
the fluid to be cooled or heated;
c) where the temperature of the heat transfer fluid of the heating system (heating water circuit) does
not exceed 105 °C during normal operation;
d) where the maximum operating pressure in the:
1) heating water circuit (if installed) does not exceed 6 bar,
2) domestic hot water circuit (if installed) does not exceed 10 bar.
This document applies to GEHP appliances only when used for space heating or space cooling or for
refrigeration, with or without heat recovery.
This document is applicable to GEHP appliances that are intended to be type tested. Requirements for
GEHP appliances that are not type tested would need to be subject to further consideration.
2 Normative references
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.
EN 16905-1:2017, Gas‐fired endothermic engine driven heat pumps — Part 1: Terms and definitions
1
EN 16905-4:— , Gas‐fired endothermic engine driven heat pumps — Part 4: Test methods
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 16905-1:2017 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/
6

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SIST EN 16905-5:2023
EN 16905-5:2022 (E)
4 Part load conditions for space cooling
4.1 General
For the purpose of calculation of application SGUE , SAEF , SEHRE , SAEHRF , SGUE , SAEF and
c c c c Tc Tc
reference SGUE , SAEF , SEHRE , SAEHRF , SGUE , SAEF as explained in Clauses 6 and 7, the part load
c c c c Tc Tc
ratios mentioned below shall be based on the part load ratio formulas with at least two decimal digits.
For the purpose of SGUE , SAEF , SEHRE , SAEHRF , SGUE , SAEF the different conditions are defined
c c c c Tc Tc
by a reference design temperature Tdesignc equal to 35 °C.
The calculation of SGUE , SAEF , SEHRE , SAEHRF , SGUE , SAEF and reference SGUE , SAEF , SEHRE ,
c c c c Tc Tc c c c
SAEHRF , SGUE , SAEF is determined via linear interpolation of the respective part load values at the
c Tc Tc
reference part load conditions mentioned below (A, B, C, D).
4.2 Air-to-air units
For outdoor air-to-recycled air units, the part load conditions for determining the declared capacity
(DC) and the declared GUE , AEF , EHRE ,, AEHRF , GUE , AEF are given in Table 1.
c c c c Tc Tc
Table 1 — Part load conditions for outdoor air-to- recycled air units
Outdoor heat Indoor heat

exchanger exchanger
Part load
Formula
ratio
Air dry bulb Air dry (wet) bulb

temperature temperatures
 % °C °C
A (35–16)/(T -16) 100,00 35 27(19)
designc
B (30–16)/(T -16) 73,68 30 27(19)
designc
C (25–16)/(T -16) 47,37 25 27(19)
designc
D (20–16)/(T -16) 21,05 20 27(19)
designc
7

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SIST EN 16905-5:2023
EN 16905-5:2022 (E)
4.3 Water-to-air and brine-to-air units
For water-to-air and brine-to-air units, the part load conditions for determining the declared capacity
(DC) and the declared GUE , AEF , EHRE ,, AEHRF , GUE , AEF are given in Table 2.
c c c c Tc Tc
Table 2 — Part load conditions for water-to-air and brine-to-air units
Indoor heat
Outdoor heat exchanger
exchanger
Cooling tower
or Ground
Part
Dry cooler
water(brine) coupled
Formula load
application Air dry (wet)
loop application
ratio
Inlet/outlet bulb
application Inlet/outlet
water temperature
Inlet/outlet water(brine)
temperatures
water(brine) temperatures
temperatures
 % °C °C °C °C
A (35–16)/(T -16) 100,00 30/35 10/15 50/55 27(19)
designc
a a a
B (30–16)/(T -16) 73,68 26/ 10/ 45/ 27(19)
designc
a a a
C (25–16)/(T -16) 47,37 22/ 10/ 40/ 27(19)
designc
a a a
D (20–16)/(T -16) 21,05 18/ 10/ 35/ 27(19)
designc
If a cooling tower and a water-to-air unit are sold as a matched assembly, they shall be tested as an air-

to-air unit.
a
With the flow rate as determined during “A” test for units with a fixed flow rate or a fixed water temperature
difference of 5 °K for units with a variable flow rate. If for any of the test conditions the resulting flow rate is below
the minimum flow rate then this minimum flow rate is used as a fixed flow rate with the inlet temperature for this
test condition.
4.4 Air-to-water and air-to-brine units
For each application, units either allowing or not allowing a variation of the outlet water/brine
temperature with the outdoor temperature are considered. The part load conditions for determining
the declared capacity (DC) and the declared GUE , AEF , EHRE , AEHRF , GUE , AEF are given in
c c c c Tc Tc
Table 3.
The variable outlet temperature (T ) shall only be applied when the control provides a
outlet,average
regulation of outlet water temperature that considers the outdoor temperature.
For the determination of water (brine) temperature for fixed capacity units with variable outlet
1
temperature refer to EN 16905-4:— .
For units with variable outlet that have to cycle on/off to reach the required part load ratio, the inlet
1
and outlet temperatures of the indoor heat exchanger shall be determined according to EN 16905-4:— ,
Annex H.
8

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SIST EN 16905-5:2023
EN 16905-5:2022 (E)
Table 3 — Part load conditions of air-to-water and air-to-brine units
Outdoor heat
Indoor heat exchanger
exchanger
Part Outdoor air Fan coil application
Cooling floor
Formula load dry bulb Inlet/outlet water(brine)
application
ratio temperature temperatures
Inlet/outlet
water(brine)
Fixed Variable

temperatures
b
outlet outlet
 % °C °C °C °C
A (35–16)/(T -16) 100,00 35 12/7 12/7 23/18
designc
a a a
B (30–16)/(T -16) 73,68 30 /7 /8,5 /18
designc
a a
/7 /10 a
C (25–16)/(T -16) 47,37 25 /18
designc
a a a
D (20–16)/(T -16) 21,05 20 /7 /11,5 /18
designc
a
With the flow rate as determined during “A” test for units with a fixed flow rate or with a fixed water
temperature difference 5 K for units with a variable flow rate. If for any of the test conditions the resulting flow
rate is below the minimum flow rate then this minimum flow rate is used as a fixed flow rate with the outlet
temperature for this test condition.
b
If the variable outlet temperature is above the maximum of the operating range of the unit, this maximum
should be considered.
4.5 Water-to-water and brine-to-water units
For each application, units either allowing or not allowing a variation of the outlet water/brine
temperature with the outdoor temperature are considered. The part load conditions for determining
the declared capacity (DC) and the declared GUE , AEF , EHRE , AEHRF , GUE , AEF are given in
c c c c Tc Tc
Table 4.
The variable outlet temperature (T ) shall only be applied when the control provides a
outlet,average
regulation of outlet water temperature that considers the outdoor temperature.
For the determination of water (brine) temperature for fixed capacity units with variable outlet
1
temperature refer to EN 16905-4:— .
For units with variable outlet that have to cycle on/off to reach the required part load ratio, the inlet
1
and outlet temperatures of the indoor heat exchanger shall be determined according to EN 16905-4:— ,
Annex H.
9

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SIST EN 16905-5:2023
EN 16905-5:2022 (E)
Table 4 — Part load conditions of water-to-water, water-to-brine, brine-to-water, brine-to-brine and DX-to-water units
Outdoor heat exchanger Indoor heat exchanger
Cooling tower or Fan coil application
Ground coupled Dry cooler
water(brine) loop Inlet/outlet water Cooling floor
DX
application application
application temperatures application
Inlet/outlet Inlet/outlet
Bath
Inlet/outlet Inlet/outlet water
water(brine) water(brine)
temperature
Variable
water(brine) temperatures
Fixed outlet
temperatures temperatures
b
outlet
temperatures
 % °C °C °C °C °C °C
(35–16) /
A 100,00 30/35 10/15 50/55 30 12/7 12/7 23/18
(Tdesignc-16)
(30–16) /
a a a a a a
B 73,68 26/ 10/ 45/ 30 /7 /8,5 /18
(Tdesignc-16)
(25–16) /
a a a a a a
C 47,37 22/ 10/ 40/ 30 /7 /10 /18
(T -16)
designc
(20–16) /
a a a a a a
D 21,05 18/ 10/ 35/ 30 /7 /11,5 /18
(T -16)
designc

If a cooling tower and water-to-water unit are sold as a matched assembly, they shall be tested as an air-to-water unit.
a
With the flow rate as determined during “A” test for units with a fixed flow rate or with a fixed water temperature difference of 5 K for units with a variable
flow rate. If for any of the test conditions the resulting flow rate is below the minimum flow rate then this minimum flow rate is used as a fixed flow rate with the
outlet temperature for this test condition.
b
If the variable outlet temperature is above the maximum of the operating range of the unit, this maximum should be considered.

10
Formula
Part load ratio

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SIST EN 16905-5:2023
EN 16905-5:2022 (E)
5 Part load conditions for space heating
5.1 General
For the purpose of calculation of SGUE , SAEF , SEHRE , SAEHRF SGUE , SAEF , and reference SGUE ,
h h h h Th Th h
SAEF , SEHRE , SAEHRF SGUE , SAEF , as explained in Clauses 6 and 7, the part load ratios mentioned
h h h Th Th
below shall be based on the part load ratio formulas with at least two decimal digits.
The calculation of SGUE , SAEF , SEHRE , SAEHRF SGUE , SAEF and reference SGUE , SAEF , SEHRE ,
h h h h Th Th h h h
SAEHRF SGUE , SAEF is determined via linear interpolation of the respective part load values at the
h Th Th
reference part load conditions mentioned below (A, B, C, D). For the purpose of reference SGUE , SAEF ,
h h
SEHRE , SAEHRF SGUE , SAEF there are three reference conditions: average(A), warmer (W) and
h h Th Th
colder (C).
The relevant T values are defined as follows:
designh
— Average dry bulb temperature conditions at − 10 °C outdoor temperature and 20 °C
climate indoor temperature;
— Colder climate dry bulb temperature conditions at − 22 °C outdoor temperature and 20 °C
indoor temperature
— Warmer dry bulb temperature conditions at + 2 °C outdoor temperature and 20 °C
climate indoor temperature
For outdoor air dry bulb temperatures higher or equal to −10 °C the wet bulb temperature equals the
dry bulb temperature minus 1 K. For dry bulb temperatures below −10 °C, the wet bulb temperature is
not defined.
For heat pumps, the relevant T is defined as follows:
biv
— for
...

SLOVENSKI STANDARD
oSIST prEN 16905-5:2021
01-december-2021
Toplotna črpalka s plinsko gnanim motorjem z notranjim zgorevanjem - 5. del:
Izračun sezonske zmogljivosti za ogrevanje in hlajenje
Gas-fired endothermic engine driven heat pumps - Part 5: Calculation of seasonal
performances in heating and cooling mode
Gasbefeuerte endothermische Motor-Wärmepumpen - Teil 5: Berechnung der
saisonalen Effizienzkennzahlen im Heiz- und Kühlmodus
Pompes à chaleur à moteur endothermique alimenté au gaz -Partie 5 : Calcul des
performances saisonnières en modes chauffage et refroidissement
Ta slovenski standard je istoveten z: prEN 16905-5
ICS:
27.080 Toplotne črpalke Heat pumps
oSIST prEN 16905-5:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 16905-5:2021

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oSIST prEN 16905-5:2021


DRAFT
EUROPEAN STANDARD
prEN 16905-5
NORME EUROPÉENNE

EUROPÄISCHE NORM

November 2021
ICS 27.080 Will supersede EN 16905-5:2017
English Version

Gas-fired endothermic engine driven heat pumps - Part 5:
Calculation of seasonal performances in heating and
cooling mode
Pompes à chaleur à moteur endothermique alimenté Gasbefeuerte endothermische Motor-Wärmepumpen -
au gaz -Partie 5 : Calcul des performances saisonnières Teil 5: Berechnung der saisonalen Effizienzkennzahlen
en modes chauffage et refroidissement im Heiz- und Kühlmodus
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 299.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 16905-5:2021 E
worldwide for CEN national Members.

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oSIST prEN 16905-5:2021
prEN 16905-5:2021 (E)
Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 7
3 Terms and definitions . 7
4 Part load conditions for space cooling . 10
4.1 General. 10
4.2 Air-to-air units . 10
4.3 Water-to-air and brine-to-air units . 11
4.4 Air-to-water and air-to-brine units . 12
4.5 Water-to-water and brine-to-water units . 12
5 Part load conditions for space heating . 13
5.1 General. 13
5.2 Air-to-air units . 14
5.3 Water-to-air units and brine-to-air units . 15
5.4 Air-to-water and air-to-brine units . 17
5.4.1 General. 17
5.4.2 Low temperature application . 17
5.4.3 Intermediate temperature application . 21
5.4.4 Medium temperature application . 24
5.5 DX-to-water, DX-to-brine, water-to-water, water-to-brine, brine-to-water and brine-
to-brine units . 27
5.5.1 General. 27
5.5.2 Low temperature application . 27
5.5.3 Intermediate temperature application . 30
5.5.4 Medium temperature application . 33
6 Calculation methods for reference SPER . 35
c
6.1 General. 35
and AEF . 36
6.2 General formula for calculation of GUEc c
6.3 General formula for calculation of EHRE and AEHRF . 36
c c
6.4 General formula for calculation of reference SGUE . 36
c
6.5 Calculation of reference SEHRE . 37
c
6.6 Calculation of reference SGUE . 37
Tc
6.7 Calculation of reference SAEF . 37
c
6.8 Calculation of reference annual cooling demand (Q ) . 38
ref,c
6.9 Calculation of reference SAEF . 38
cON
6.10 Calculation of reference SAEHRF . 39
c
6.11 Calculation of reference total SAEFTc . 39
6.12 Procedures for the determination of GUE / AEF values . 39
cPL cPL
6.13 Procedures for the determination of EHRE / AEHRF values . 39
cPL cPL
6.14 Calculation of reference SPER . 40
c
6.15 Calculation of the annual primary energy consumption cooling Q . 40
CP
6.16 Calculation of the seasonal space cooling efficiency η . 40
s,c
2

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oSIST prEN 16905-5:2021
prEN 16905-5:2021 (E)
7 Calculation methods for reference SPER . 41
h
7.1 General . 41
7.2 General formula for calculation of GUE and AEF . 41
h h
7.3 General formula for calculation of EHRE . 41
h
7.4 General formula for calculation of reference SGUE . 41
h
7.5 Calculation of reference SEHRE . 44
h
7.6 Calculation of reference SGUE . 45
Th
7.7 Calculation of reference SAEF . 45
h
7.8 Calculation of reference annual heating demand (Qref,h) . 45
7.9 Calculation of reference SAEF . 45
hON
7.10 Calculation of reference SAEHRF . 46
h
7.11 Calculation of reference total SAEF . 47
Th
7.12 Procedures for the determination of GUE / AEF values . 47
hPL hPL
7.13 Procedures for the determination of EHRE / AEHRF values . 47
hPL hPL
7.14 Calculation of reference SPER . 47
h
7.15 Calculation of the annual primary energy consumption heating Q . 47
HP
7.16 Calculation of the seasonal space heating efficiency η . 48
s,h
Annex A (normative) Determination of reference annual cooling/heating demands and
determination of hours for active mode, thermostat off, standby, off mode and
crankcase heater mode for reference SAEF and SAEF calculation . 49
c h
Annex B (informative) Calculation example for reference SGUE , SAEF , SEHRE , SAEHRF ,
c c c c
SGUE , SAEF and SPER . 51
Tc Tc c
Annex C (informative) Calculation example for reference SGUE , SAEF , SEHRE , SAEHRF ,
h h h h
SGUE , SAEF and SPER . 55
Tc Th h
Annex D (informative) Determination of water (brine) temperature for fixed capacity units
with variable outlet temperature . 59
Annex E (informative) Template for technical documentation . 60
Annex F (informative) Compensation method for air to water and water to water units . 65
Annex G (normative) Rating of outdoor units of multi-split air conditioners and heat pumps . 66
G.3 Rating of outdoor units . 67
G.3.1 General . 67
G.3.2 Test procedure . 68
G.4 Calculation of the SPER based on the PER . 68
c c outdoor
G.5 Calculation of the SPER based on the SPER . 68
h h outdoor
Annex ZA (informative) Relationship between this European Standard and the
requirements of Commission Regulation (EU) No 813/2013 aimed to be covered
(ErP Lot1) . 69
Annex ZB (informative) Relationship between this European Standard and the
requirements of Commission Regulation (EU) No 2016/2281 aimed to be covered . 70
Annex ZC (informative) Relationship between this European Standard and the
requirements of Commission Regulation (EU) No 811/2013 aimed to be covered . 71
Bibliography . 72
3

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oSIST prEN 16905-5:2021
prEN 16905-5:2021 (E)
European foreword
This document (prEN 16905-5:2021) has been prepared by Technical Committee CEN/TC 299 “Gas-
fired sorption appliances, indirect fired sorption appliances, gas-fired endothermic engine heat pumps
and domestic gas-fired washing and drying appliances”, the secretariat of which is held by UNI.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 16905-5:2017.
In comparison with the previous edition, the following technical modifications have been made:
Editorial and technical changes throughout the draft and in Annex ZA, ZB and ZC in order to align the
text to the Ecodesign Requirements stated in Commission Regulation (EU) No 2016/426.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EU Directive(s).
For relationship with EU Directive(s), see informative Annex ZA, Annex ZB and Annex ZC which are
integral parts of this document.
4

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oSIST prEN 16905-5:2021
prEN 16905-5:2021 (E)
Introduction
The GEHP appliances having their condenser cooled by air and by the evaporation of external additional
water are not covered by this European Standard.
Single split and multisplit systems are covered by this document.
The GEHP appliances can have one or more primary or secondary functions.
This document specifies the calculation of seasonal performances in heating and cooling mode of air
conditioners and heat pumps using either air, water or brine as heat transfer media, with gas-fired
endothermic engine driven compressors when used for space heating, cooling and refrigeration,
hereafter referred to as “GEHP appliance”
EN 16905 comprises the following parts under the general title, Gas-fired endothermic
engine driven heat pumps:
— Part 1: Terms and definitions;
— Part 2: Safety;
— Part 3: Tests conditions;
— Part 4: Tests methods;
— Part 5: Calculation of seasonal performances in heating and cooling mode.
prEN 16905-5:2021 has been prepared to address the essential requirements of the European
Regulation (EU) 2016/426 relating to appliances burning gaseous fuels and repealing Directive
2009/142/EC (see EN 16905-4:2020, Annex ZA).
EN 16905-1:2017, EN 16905-2:2020, EN 16905-3:2017, EN 16905-4:2017 and EN 16905-5:2017 are
linked to the Energy Related Products Directive (2009/125/EC) in terms of tests conditions, tests
methods and seasonal performances calculation methods under Mandate M/535; (see EN 16905-
3:2017, Annex ZA, EN 16905-4:2017, Annex ZA, EN 16905-5:2017, Annex ZA and EN 16905-2:2020,
Annexes ZB and ZC).
These documents will be reviewed whenever new mandates could apply.
5

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oSIST prEN 16905-5:2021
prEN 16905-5:2021 (E)
1 Scope
This part of EN 16905 specifies the calculation of the seasonal performance factor for gas-fired
endothermic engine driven heat pumps for heating and/or cooling mode including the engine heat
recovery, to be used outdoor.
This document is used in conjunction with:
a) the terms and conditions, EN 16905-1:2017
b) the safety, EN 16905-2:2021
c) the test conditions, EN 16905-3:2017
d) the test methods, EN 16905-4:2021
e) the heat pump standards, EN 14511-2:2018, EN 14511-3:2018 and EN 14825:2018.
This document only applies to appliances with a maximum heat input (based on net calorific value) not
exceeding 70 kW at standard rating conditions.
This document only applies to appliances under categories I , I , I , I , I , I , I , I , I , I ,
2H 2E 2Er 2R 2E(S)B 2L 2LL 2ELL 2E(R)B 2ESi
I , I , I , I , II , II , II , II , II , II , II , II , II and II according to
2E(R) 3P 3B 3B/P 2H3+ 2Er3+ 2H3B/P 2L3B/P 2E3B/P 2ELL3B/P 2L3P 2H3P 2E3P 2Er3P
EN 437:2003 + A1:2009.
This document only applies to appliances having:
a) gas fired endothermic engines under the control of fully automatic control systems;
b) closed system refrigerant circuits in which the refrigerant does not come into direct contact with
the fluid to be cooled or heated;
c) where the temperature of the heat transfer fluid of the heating system (heating water circuit) does
not exceed 105 °C during normal operation;
d) where the maximum operating pressure in the:
1) heating water circuit (if installed) does not exceed 6 bar,
2) domestic hot water circuit (if installed) does not exceed 10 bar.
This document applies to GEHP appliances only when used for space heating or space cooling or for
refrigeration, with or without heat recovery.
This document is applicable to GEHP appliances that are intended to be type tested. Requirements for
GEHP appliances that are not type tested would need to be subject to further consideration.
6

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oSIST prEN 16905-5:2021
prEN 16905-5:2021 (E)
2 Normative references
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.
EN 16905-1:2017, Gas-fired endothermic engine driven heat pumps - Part 1: Terms and definitions
EN 16905-4:2017, Gas-fired endothermic engine driven heat pumps - Part 4: Test methods
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 16905-1 and the following
apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1
equivalent active mode hours for cooling
H
CE
assumed annual number of hours while the unit is assumed to operate at the design load for space
cooling (Pdesignc) in order to satisfy the reference annual space cooling demand
Note 1 to entry: Expressed in hours [h].
3.2
equivalent active mode hours for heating
H
HE
assumed annual number of hours while the unit is assumed to operate at the design load for space
heating (Pdesignh) in order to satisfy the reference annual space heating demand
Note 1 to entry: Expressed in hours [h].
3.3
annual primary energy consumption cooling
QCP
reference annual cooling demand divided by the seasonal primary energy ratio cooling
3.4
annual primary energy consumption heating
Q
HP
reference annual heating demand divided by the seasonal primary energy ratio heating
3.5
seasonal space cooling energy efficiency
η
s,c
ratio between the space cooling demand for the cooling season, supplied by a space cooling unit and the
annual energy consumption required to meet this demand
Note 1 to entry: Expressed in %.
7

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oSIST prEN 16905-5:2021
prEN 16905-5:2021 (E)
3.6
seasonal space heating energy efficiency
η
s,h
ratio between the space heating demand for a designated heating season, supplied by a space heater
and the annual energy consumption required to meet this demand
Note 1 to entry: Expressed in %.
3.7
reference seasonal gas utilization efficiency ratio in cooling mode
SGUE
c
seasonal gas utilization efficiency ratio, expressed in GCV, of a GEHP appliance calculated for the
reference annual space cooling demand
Note 1 to entry: The reference seasonal gas utilization efficiency ratio in cooling mode is expressed in
kilowatt/kilowatt (kW/kW).
3.8
reference seasonal gas utilization efficiency ratio in heating mode
SGUE
h
seasonal gas utilization efficiency ratio, expressed in GCV, of a GEHP appliance calculated for the
reference annual space heating demand
Note 1 to entry: The reference seasonal gas utilization efficiency ratio in heating mode is expressed in
kilowatt/kilowatt (kW/kW).
3.9
reference seasonal auxiliary energy factor in cooling mode
SAEFc
seasonal auxiliary energy factor of a GEHP appliance calculated for the reference annual space cooling
demand, including the energy consumption during active mode, thermostat off mode, standby mode
and off mode
Note 1 to entry: The reference seasonal auxiliary energy factor in cooling mode is expressed in kilowatt/kilowatt
(kW/kW).
3.10
reference seasonal auxiliary energy factor in heating mode
SAEFh
seasonal auxiliary energy factor of a GEHP appliance calculated for the reference annual space heating
demand, including the energy consumption during active mode, thermostat off mode, standby mode
and off mode
Note 1 to entry: The reference seasonal auxiliary energy factor in heating mode is expressed in kilowatt/kilowatt
(kW/kW).
3.11
reference seasonal primary energy ratio in cooling mode
SPER
c
seasonal primary energy ratio of a GEHP appliance calculated for the reference annual space cooling
demands
Note 1 to entry: The reference seasonal primary energy ratio in cooling mode is expressed in kilowatt/kilowatt
(kW/kW)
8

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oSIST prEN 16905-5:2021
prEN 16905-5:2021 (E)
3.12
reference seasonal primary energy ratio in heating mode
SPER
h
seasonal primary energy ratio of a GEHP appliance calculated for the reference annual space heating
demands
Note 1 to entry: The reference seasonal primary energy ratio in heating mode is expressed in kilowatt/kilowatt
(kW/kW).
3.13
reference seasonal engine heat recovery efficiency in cooling mode
SEHRE
C
seasonal engine heat recovery efficiency expressed in GCV, of a GEHP appliance calculated for the
reference annual space cooling demand
Note 1 to entry: The reference seasonal engine heat recovery efficiency in cooling mode is expressed in
kilowatt/kilowatt (kW/kW).
3.14
reference seasonal engine heat recovery efficiency in heating mode
SEHRE
h
seasonal engine heat recovery efficiency expressed in GCV, of a GEHP appliance calculated for the
reference annual space heating demand
Note 1 to entry: The reference seasonal engine heat recovery efficiency in heating mode is expressed in
kilowatt/kilowatt (kW/kW).
3.15
reference seasonal auxiliary engine heat recovery factor in cooling mode
SAEHRF
C
seasonal auxiliary engine heat recovery factor, of a GEHP appliance calculated for the reference annual
space cooling demand
Note 1 to entry: The reference seasonal auxiliary engine heat recovery factor in cooling mode is expressed in
kilowatt/kilowatt (kW/kW).
3.16
reference seasonal auxiliary engine heat recovery factor in heating mode
SAEHRF
h
seasonal auxiliary engine heat recovery factor, of a GEHP appliance calculated for the reference annual
space heating demand
Note 1 to entry: The reference seasonal auxiliary engine heat recovery factor in heating mode is expressed in
kilowatt/kilowatt (kW/kW).
3.17
reference total seasonal gas utilization efficiency ratio in cooling mode
SGUE
Tc
total seasonal gas utilization efficiency ratio, expressed in GCV, of a GEHP appliance calculated for the
reference annual space cooling demand
Note 1 to entry: The reference total seasonal gas utilization efficiency ratio in cooling mode is expressed in
kilowatt/kilowatt (kW/kW).
9

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oSIST prEN 16905-5:2021
prEN 16905-5:2021 (E)
3.18
reference total seasonal gas utilization efficiency ratio in heating mode
SGUE
Th
total seasonal gas utilization efficiency ratio, expressed in GCV, of a GEHP appliance calculated for the
reference annual space heating demand
Note 1 to entry: The reference total seasonal gas utilization efficiency ratio in heating mode is expressed in
kilowatt/kilowatt (kW/kW).
3.19
reference seasonal auxiliary energy factor in cooling mode
SAEF
Tc
total seasonal auxiliary energy factor of a GEHP appliance calculated for the reference annual space
cooling demand
Note 1 to entry: The reference total seasonal auxiliary energy factor in cooling mode is expressed in
kilowatt/kilowatt (kW/kW).
3.20
reference seasonal auxiliary energy factor in heating mode
SAEF
Th
total seasonal auxiliary energy factor of a GEHP appliance calculated for the reference annual space
heating demand
Note 1 to entry: The reference total seasonal auxiliary energy factor in heating mode is expressed in
kilowatt/kilowatt (kW/kW).
3.21
variable outlet temperature
T
outlet,average
water(brine) outlet temperature that is used when the control of the unit has means to automatically
vary the water(brine) outlet temperature with the outdoor temperature
4 Part load conditions for space cooling
4.1 General
For the purpose of calculation of application SGUE , SAEF , SEHRE , SAEHRF , SGUE , SAEF and
c c c c Tc Tc
reference SGUE , SAEF , SEHRE , SAEHRF , SGUE , SAEF as explained in Clauses 6 and 7, the part load
c c c c Tc Tc
ratios mentioned below shall be based on the part load ratio formulas with at least two decimal digits.
For the purpose of SGUE , SAEF , SEHRE , SAEHRF , SGUE , SAEF the different conditions are defined
c c c c Tc Tc
by a reference design temperature Tdesignc equal to 35 °C.
The calculation of SGUE , SAEF , SEHRE , SAEHRF , SGUE , SAEF and reference SGUE , SAEF , SEHRE ,
c c c c Tc Tc c c c
SAEHRF , SGUE , SAEF is determined via linear interpolation of the respective part load values at the
c Tc Tc
reference part load conditions mentioned below (A, B, C, D).
4.2 Air-to-air units
For outdoor air-to-recycled air units, the part load conditions for determining the declared capacity
(DC) and the declared GUEc, AEFc, EHREc,, AEHRFc, GUETc, AEFTc are given in Table 1.
10

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oSIST prEN 16905-5:2021
prEN 16905-5:2021 (E)
Table 1 — Part load conditions for outdoor air-to- recycled air units
 Outdoor heat Indoor heat
exchanger exchanger
Part load
Formula
ratio
 Air dry bulb Air dry (wet) bulb
temperature temperatures
  % °C °C
A (35–16)/(T -16) 100,00 35 27(19)
designc
B (30–16)/(T -16) 73,68 30 27(19)
designc
C (25–16)/(T -16) 47,37 25 27(19)
designc
D (20–16)/(T -16) 21,05 20 27(19)
designc
4.3 Water-to-air and brine-to-air units
For water-to-air and brine-to-air units, the part load conditions for determining the declared capacity
(DC) and the declared GUE , AEF , EHRE ,, AEHRF , GUE , AEF are given in Table 2.
c c c c Tc Tc
T
...

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