Roof-top units

This document specifies the terms and definitions, the test conditions and the test methods of air-sourced and water-cooled roof-top units, driven by electric compressor(s), which may be equipped with a supplementary heater using electrical resistance or combustion of fossil fuel.
This document covers roof-top units with 2, 3 or 4 dampers, including several features as the free-cooling, mixing air flows (on both sides) and heat recovery.
This document deals with roof-top units providing space heating and/or cooling for comfort application. Process applications are not covered by this document.
This document provides the part load conditions and the calculation methods taking into account roof-top units features for the determination of seasonal energy efficiency SEER and SEERon, seasonal space cooling energy efficiency ηs,c, seasonal coefficient of performance SCOP, SCOPon and SCOPnet, seasonal space heating energy efficiency ηs,h and the overall annual efficiency.
Such calculation methods may be based on calculated or measured values.
In case of measured values, this document covers the test methods for determination of capacities, EER and COP values during active mode at part load conditions. It also covers test methods for the determination of power input during thermostat-off mode, standby mode, off-mode and crankcase heater mode.
A roof-top unit that is not using at least the thermodynamic cycle for space heating is considered as a cooling only unit.
Roof-top units equipped with additional air heating and/or cooling heat exchangers will be rated without operation of these heat exchangers.

Dachgeräte

Dieses Dokument legt die Begriffe, die Prüfbedingungen und Prüfverfahren für Dachgeräte mit elektrisch angetriebenem(n) Verdichter(n) fest, die mit einem zusätzlichen Heizgerät ausgestattet sein können und einen elektrischen Widerstand oder die Verbrennung fossiler Brennstoffe verwenden.
Dieses Dokument deckt Luft/Luft-Geräte mit integrierten Innen- und Außenlüftern sowie Wasser/Sole-Luft-Geräte mit integriertem(n) Innenventilator(en) und integrierter oder nicht integrierter Flüssigkeitspumpe ab.
Dieses Dokument deckt Dachgeräte mit 2, 3 oder 4 Klappen, einschließlich mehrerer Merkmale wie freie Kühlung, Mischung von Luftströmen (auf beiden Seiten) und Wärmerückgewinnung ab.
Dieses Dokument behandelt Dachgeräte, die Raumheizung und/oder -kühlung für Komfortzwecke ermöglichen. Prozessanwendungen werden in diesem Dokument nicht behandelt.
Dieses Dokument enthält die Teillastbedingungen sowie, unter Berücksichtigung der Merkmale von Dachgeräten, Berechnungsverfahren zur Ermittlung der saisonalen Arbeitszahl im Kühlbetrieb SEER und SEERon, der jahreszeitbedingten Raumkühlungs-Energieeffizienz ηs,c der saisonalen Arbeitszahl im Heizbetrieb SCOP, SCOPon und SCOPnet, der jahreszeitbedingten Raumheizungs-Energieeffizienz ηs,h sowie der Gesamtjahreseffizienz.
Derartige Berechnungsverfahren können auf Rechen- oder Messwerten beruhen.
Im Fall von Messwerten behandelt dieses Dokument die Prüfverfahren zur Ermittlung von Leistungen, EER- und COP-Werten im Aktiv-Modus unter Teillastbedingungen. Außerdem behandelt es Prüfverfahren zur Ermittlung der Leistungsaufnahme im Modus „Temperaturregler AUS“, im Bereitschaftsmodus, im Modus „Aus“ und im Modus mit Kurbelgehäuseheizung.
Ein Dachgerät, das nicht mindestens den thermodynamischen Kreislauf für die Raumheizung nutzt, wird als reines Kühlgerät betrachtet.
Für die Anwendung dieses Dokuments werden Dachgeräte, die mit zusätzlichen Wärmeaustauschern für die Luftheizung oder -kühlung ausgestattet sind, ohne Betrieb dieser Wärmeaustauscher bewertet.

Unités de toiture

Le présent document précise les termes et définitions, les conditions d'essai et les méthodes d'essai des unités de toiture avec compresseur(s) entraîné(s) par moteur électrique, qui peuvent être équipées d'un dispositif de chauffage d'appoint utilisant la résistance électrique ou la combustion de combustible fossile.
Le présent document couvre les appareils air/air avec ventilateurs intérieurs et extérieurs intégrés ainsi que les appareils eau(glycolée)/air avec ventilateur(s) intérieur(s) intégré(s) et pompe de circulation intégrée ou non.
Le présent document couvre les unités de toiture à 2, 3 ou 4 volets, comprenant plusieurs caractéristiques comme le refroidissement gratuit, le mélange des flux d'air (des deux côtés) et la récupération de chaleur.
Le présent document traite des unités de toiture assurant le chauffage et/ou le refroidissement des locaux pour une application de confort. Les applications industrielles ne sont pas couvertes par le présent document.
Le présent document fournit les conditions de charge partielle et les méthodes de calcul tenant compte des caractéristiques des unités de toiture pour la détermination de l'efficacité énergétique saisonnière SEER et SEERon, de l'efficacité énergétique saisonnière du refroidissement des locaux ηs,c, du coefficient de performance saisonnier SCOP, SCOPon et SCOPnet, de l'efficacité énergétique saisonnière du chauffage des locaux ηs,h et de l'efficacité annuelle globale.
Ces méthodes de calcul peuvent être basées sur des valeurs calculées ou mesurées.
Dans le cas de valeurs mesurées, le présent document couvre les méthodes d'essai relatives à la détermination des puissances et des valeurs d'EER et de COP pendant le mode actif, dans les conditions de charge partielle. Il couvre également les méthodes d'essai relatives à la puissance absorbée en mode arrêt par thermostat, en mode veille, en mode arrêt et en mode dispositif de chauffage de carter.
Une unité de toiture qui n'utilise pas au moins le cycle thermodynamique pour le chauffage des locaux est considérée comme un dispositif de refroidissement uniquement.
Pour les besoins du présent document, les unités de toiture équipées d'échangeurs de chaleur supplémentaires pour le chauffage et/ou le refroidissement de l'air sont évaluées sans le fonctionnement de ces échangeurs de chaleur.

Klimatske strešne enote

General Information

Status
Not Published
Public Enquiry End Date
02-Jan-2021
Technical Committee
Current Stage
4020 - Public enquire (PE) (Adopted Project)
Start Date
23-Oct-2020
Due Date
12-Mar-2021
Completion Date
16-Feb-2021

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SLOVENSKI STANDARD
oSIST prEN 17625:2020
01-december-2020
Klimatske strešne enote
Roof-top units
Dachgeräte
Unités de toiture
Ta slovenski standard je istoveten z: prEN 17625
ICS:
91.140.30 Prezračevalni in klimatski Ventilation and air-
sistemi conditioning systems
oSIST prEN 17625:2020 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 17625:2020
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oSIST prEN 17625:2020
DRAFT
EUROPEAN STANDARD
prEN 17625
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2020
ICS 91.140.30
English Version
Roof-top units
Unités de toiture Dachgeräte

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 113.

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

© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 17625:2020 E

worldwide for CEN national Members.
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oSIST prEN 17625:2020
prEN 17625:2020 (E)
Contents Page

European foreword ....................................................................................................................................................... 5

1 Scope .................................................................................................................................................................... 6

2 Normative references .................................................................................................................................... 6

3 Terms, definitions, symbols and units .................................................................................................... 7

3.1 Terms and definitions ................................................................................................................................... 7

3.2 Symbols, abbreviated terms and units ................................................................................................. 20

4 Test conditions .............................................................................................................................................. 22

4.1 Standard rating conditions ....................................................................................................................... 22

4.2 Part load conditions .................................................................................................................................... 23

4.2.1 Cooling mode ................................................................................................................................................. 23

4.2.2 Heating mode ................................................................................................................................................. 25

5 Test apparatus............................................................................................................................................... 26

5.1 General requirements ................................................................................................................................ 26

5.2 Test room ........................................................................................................................................................ 26

5.3 Appliances with duct connection ........................................................................................................... 26

5.4 Installation and connection of the test object.................................................................................... 26

5.4.1 General ............................................................................................................................................................. 26

5.4.2 Measuring points .......................................................................................................................................... 26

5.5 Uncertainties of measurement ................................................................................................................ 27

6 Settings ............................................................................................................................................................. 29

6.1 Settings of supply air ................................................................................................................................... 29

6.2 Setting on the outdoor heat exchanger side ....................................................................................... 30

6.2.1 Non ducted units ........................................................................................................................................... 30

6.2.2 Ducted units ................................................................................................................................................... 30

6.2.3 Water-source units ...................................................................................................................................... 31

6.2.4 Units with integrated liquid pumps ...................................................................................................... 31

7 Capacity and power input calculations ................................................................................................ 31

7.1 Basic principles for the determination of capacities ...................................................................... 31

7.2 Effective power input correction ............................................................................................................ 31

7.2.1 General ............................................................................................................................................................. 31

7.2.2 Power input correction of fans for units without duct connection ............................................ 32

8 Capacity test method ................................................................................................................................... 33

8.1 Permissible deviations ............................................................................................................................... 33

8.1.1 Output measurement for water-sourced units ................................................................................. 34

8.1.2 Output measurement for cooling capacity of air-sourced units ................................................. 35

8.1.3 Output measurement for heating capacity of air-sourced units ................................................. 35

8.2 Test results ..................................................................................................................................................... 40

8.2.1 Data to be recorded ..................................................................................................................................... 40

8.2.2 Cooling capacity and heat recovery capacity calculation .............................................................. 42

8.2.3 Heating capacity calculation .................................................................................................................... 43

8.2.4 Effective power input calculation........................................................................................................... 43

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9 Auxiliary modes ............................................................................................................................................ 43

9.1 Uncertainties of measurement ................................................................................................................ 43

9.2 Measurement of electric power input during thermostat-off mode .......................................... 44

9.3 Measurement of the electric power input during standby mode ................................................ 44

9.4 Measurement of the electric power input during crankcase heater mode ............................. 44

9.5 Measurement of the electric power input during off mode .......................................................... 45

10 Seasonal performance ................................................................................................................................ 45

10.1 Calculation of SEER and SEER ................................................................................................................ 45

10.1.1 General formula for calculation of SEER ............................................................................................... 45

10.1.2 Calculation of the reference annual cooling demand Q ................................................................ 45

10.1.3 Calculation of the reference annual energy consumption for cooling Q ............................... 45

10.1.4 Calculation of SEER .................................................................................................................................... 46

10.1.5 Calculation procedure for determination of EER values at part load conditions .............. 47

bin

10.2 Calculation of SCOP, SCOP and SCOP ............................................................................................... 48

on net

10.2.1 General formula for calculation of SCOP .............................................................................................. 48

10.2.2 Calculation of the reference annual heating demand Q ................................................................ 48

10.2.3 Calculation of the annual energy consumption for heating Q ................................................... 48

10.2.4 Calculation of SCOP and SCOP ............................................................................................................ 49

on net

10.2.5 Calculation procedure for determination of COP values at part load conditions ............. 51

bin

10.3 Determination of the degradation coefficient Cd .............................................................................. 52

10.3.1 General ............................................................................................................................................................. 52

10.3.2 Air-to-air units – Cooling mode................................................................................................................ 53

10.3.3 Air-to-air units – Heating mode ............................................................................................................... 53

10.3.4 Water(brine)-to-air units – Cooling mode ........................................................................................... 53

10.3.5 Water(brine)-to-air units – Heating mode .......................................................................................... 53

11 Test methods for electric power input during thermostat-off mode, standby mode

and crankcase heater mode and off mode ........................................................................................... 54

11.1 Measurement of the electric power input during crankcase heater mode ............................. 54

12 Test report ...................................................................................................................................................... 54

12.1 General information .................................................................................................................................... 54

12.2 Additional information ............................................................................................................................... 55

12.3 Rating test results ......................................................................................................................................... 55

12.3.1 General ............................................................................................................................................................. 55

12.3.2 Seasonal test results .................................................................................................................................... 55

12.4 Specific information of the unit ............................................................................................................... 55

13 Marking ............................................................................................................................................................ 56

Annex A (informative) Illustration of rooftop unit configurations.......................................................... 57

A.1 General ............................................................................................................................................................. 57

A.2 2-damper rooftop unit ................................................................................................................................ 57

A.3 3-damper rooftop unit ................................................................................................................................ 58

A.4 4-damper rooftop unit ................................................................................................................................ 60

Annex B (normative) Indoor air enthalpy test method ............................................................................... 62

B.1 General ............................................................................................................................................................. 62

B.2 Determination of the air flow rate .......................................................................................................... 62

B.3 Calculations-cooling capacities ............................................................................................................... 62

B.4 Calculations-heating capacities ............................................................................................................... 63

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oSIST prEN 17625:2020
prEN 17625:2020 (E)

Annex C (informative) Symbols used in Annexes .......................................................................................... 64

Annex D (normative) Determination of the liquid pump efficiency ....................................................... 66

D.1 General ............................................................................................................................................................. 66

D.2 Hydraulic power of the liquid pump ..................................................................................................... 66

D.2.1 The liquid pump is an integral part of the unit ................................................................................. 66

D.2.2 The liquid pump is not an integral part of the unit .......................................................................... 66

D.3 Efficiency of integrated pumps ................................................................................................................ 67

D.3.1 Glandless circulators .................................................................................................................................. 67

D.3.2 Dry motor pumps ......................................................................................................................................... 67

D.4 Efficiency of non-integrated pumps ...................................................................................................... 69

Annex E (normative) Air flow rate measurement ......................................................................................... 70

E.1 General ............................................................................................................................................................. 70

E.2 Test installation ............................................................................................................................................ 70

E.3 Test conditions .............................................................................................................................................. 70

E.4 Air flow measurement ................................................................................................................................ 70

Annex F (informative) Climate bins and hours .............................................................................................. 71

F.1 Bin limit temperature ................................................................................................................................. 71

F.2 Cooling.............................................................................................................................................................. 71

F.3 Heating ............................................................................................................................................................. 72

F.4 Hours for active, thermostat-off, standby and off modes .............................................................. 73

F.4.1 Cooling.............................................................................................................................................................. 73

F.4.2 Heating ............................................................................................................................................................. 74

F.5 Hours used for crankcase heater mode ............................................................................................... 74

F.5.1 Cooling.............................................................................................................................................................. 74

F.5.2 Heating ............................................................................................................................................................. 74

Bibliography ................................................................................................................................................................. 75

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oSIST prEN 17625:2020
prEN 17625:2020 (E)
European foreword

This document (prEN 17625:2020) has been prepared by Technical Committee CEN/TC 113 “Heat

pumps and air conditioning units”, the secretariat of which is held by UNE.
This document is currently submitted to the CEN Enquiry.
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oSIST prEN 17625:2020
prEN 17625:2020 (E)
1 Scope

This document specifies the terms and definitions, the test conditions and the test methods of rooftop

units with electrically driven compressor(s), which may be equipped with a supplementary heater using

electrical resistance or combustion of fossil fuel.

This document covers air-to-air units with integrated indoor and outdoor fans as well as water(brine)-

to-air units with integrated indoor fan(s) and integrated or not liquid pump.

This document covers rooftop units with 2, 3 or 4 dampers, including several features as the free-cooling,

mixing air flows (on both sides) and heat recovery.

This document deals with rooftop units providing space heating and/or cooling for comfort application.

Process applications are not covered by this document.

This document provides the part load conditions and the calculation methods taking into account rooftop

units features for the determination of seasonal energy efficiency SEER and SEER , seasonal space

cooling energy efficiency η , seasonal coefficient of performance SCOP, SCOP and SCOP , seasonal

s,c on net
space heating energy efficiency η and the overall annual efficiency.
s,h
Such calculation methods may be based on calculated or measured values.

In case of measured values, this document covers the test methods for determination of capacities, EER

and COP values during active mode at part load conditions. It also covers test methods for the

determination of power input during thermostat-off mode, standby mode, off-mode and crankcase heater

mode.

A rooftop unit that is not using at least the thermodynamic cycle for space heating is considered as a

cooling only unit.

For the purpose of this document, rooftop units equipped with additional air heating and/or cooling heat

exchangers are rated without operation of these heat exchangers.
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 14511-1:2018, Air conditioners, liquid chilling packages and heat pumps for space heating and cooling

and process chillers, with electrically driven compressors - Part 1: Terms and definitions

EN 14511-2:2018, Air conditioners, liquid chilling packages and heat pumps for space heating and cooling

and process chillers, with electrically driven compressors - Part 2: Test conditions

EN 14511-3:2018, Air conditioners, liquid chilling packages and heat pumps for space heating and cooling

and process chillers, with electrically driven compressors - Part 3: Test methods

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oSIST prEN 17625:2020
prEN 17625:2020 (E)
3 Terms, definitions, symbols and units
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

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

— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1.1
exhaust air
air from the air conditioned space entering the outdoor heat exchanger
3.1.2
recycled air
air from the air conditioned space entering the indoor heat exchanger
3.1.3
extracted air

air removed from the conditioned space and rejected outdoors without entering the indoor nor outdoor

heat exchanger

Note 1 to entry: The extracted air may be entering a heat recovery device to enhance the efficiency of the unit.

3.1.4
outdoor air
air from the outdoor environment
3.1.5
supply air

air leaving the indoor heat exchanger for entering the space that is to be air conditioned

3.1.6
rooftop

unit capable of space cooling or heating, or both, using a vapour compression cycle driven by electric

compressor(s), a mixture of outdoor air and recycled air on the indoor heat exchanger, and/or a mixture

of outdoor air and exhaust air on the outdoor heat exchanger, that may be equipped with a heat recovery

device and supplementary heaters
Note 1 to entry: Air mixtures ratio can vary from 0 to 100 %.
Note 2 to entry: It can have means for cleaning and dehumidifying the air.
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oSIST prEN 17625:2020
prEN 17625:2020 (E)
3.1.7
single-package rooftop

factory-made assembly constituting a unique functional unit provided by the manufacturer, that can be

provided on one or two separate frames
3.1.8
2-damper rooftop

rooftop including indoor fan(s) for air supply, one damper on the recycled air circuit and one damper on

the outdoor air circuit that allows to vary the ratio of outdoor air into the indoor heat exchanger from 0

to 100%
Note 1 to entry: See Figures A.1.
3.1.9
3-damper rooftop

rooftop including fan(s) for air supply and fan(s) for air extraction, one damper on the recycled air circuit,

one damper on the outdoor air circuit and a third damper on the extract air circuit ahead of the air

extraction fan, with both fans functioning simultaneously that allows to vary the ratio of outdoor air into

the indoor heat exchanger from 0 to 100%

Note 1 to entry: The extracted air can be mixed with outdoor air before entering the outdoor heat exchanger.

Note 2 to entry: See Figures A.2 and A.3.
3.1.10
4-damper rooftop

rooftop equipped with four dampers for providing mixtures of outdoor air and exhaust air at the inlet of

both outdoor heat exchanger and indoor heat exchanger that allows to vary independently the ratio of

outdoor air entering both heat exchangers from 0 to 100%
Note 1 to entry: See Figures A.4 and A.5.
3.1.11
space heating mode

operation of the rooftop providing space heating by means of the thermodynamic cycle and/or

supplementary heater, where relevant
3.1.12
space cooling mode

operation of the rooftop providing space cooling by means of the active cooling and/or free cooling

modes, where relevant
3.1.13
active cooling mode

operation mode of the rooftop in which the cooling capacity, partially or totally, is only provided by the

use of thermodynamic cycle
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oSIST prEN 17625:2020
prEN 17625:2020 (E)
3.1.14
free cooling mode

operating mode of the rooftop in which cooling is provided by direct supply of outdoor air or of a mixture

of outdoor air/recycled air to air conditioned space without using the thermodynamic cycle

Note 1 to entry: If free cooling cannot provide the total cooling capacity, the active cooling mode can be activated

to compensate for the missing cooling capacity.
3.1.15
free space cooling mode

operation of the rooftop when the outdoor air or a mixture of outdoor air/recycled air is directly entering

the space to be air conditioned, without any thermodynamic cycle in use
3.1.16
supplementary heater

any hot water coil, electrical, or fossil fuel heater that is used to provide the missing heating capacity of

the thermodynamic cycle and considered in the calculation of seasonal performance regardless whether

it is integrated in the rooftop or not
3.1.17
heat recovery device

any device capable to recover an amount of energy from the extracted air for the purpose of improving

the overall rooftop efficiency
3.1.18
free cooling temperature
free

highest outdoor temperature that allows to switch the thermodynamic cycle to fulfil the room

temperature requirements
3.1.19
active mode

mode corresponding to the hours with a space cooling or heating load of the building and whereby the

cooling or heating function of the unit is activated

Note 1 to entry: This condition may involve on/off-cycling of the unit in order to reach or maintain a required

indoor air temperature.
3.1.20
active mode seasonal coefficient of performance
SCOP

average coefficient of performance of the unit in active mode for the designated heating season,

determined from the part load, supplementary heating capacity (where required) and bin-specific

coefficients of performance (COP (T )) and weighted by the bin hours where the bin condition occurs

bin j

Note 1 to entry: For calculation of SCOPon, the energy consumption during thermostat-off mode, standby mode,

off mode and crankcase heater mode is excluded. The energy consumption of a supplementary heater is added for

the part load conditions where the declared capacity of the unit is lower than the heating load, regardless whether

this supplementary heater is included in the unit or not included in the unit.
Note 2 to entry: Expressed in kWh/kWh.
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oSIST prEN 17625:2020
prEN 17625:2020 (E)
3.1.21
active mode seasonal energy efficiency ratio
SEER

average energy efficiency ratio of the unit in active mode for the space cooling function, determined from

part load and bin-specific energy efficiency ratios (EER (T )) and weighted by the bin hours where the

bin j
bin condition occurs

Note 1 to entry: For calculation of SEERon, energy consumption during thermostat-off mode, standby mode, off

mode and that of the crankcase heater is excluded.
Note 2 to entry: Expressed in kWh/kWh.
3.1.22
annual energy consumption for space cooling

energy consumption required to meet the reference annual space cooling demand and calculated as the

reference annual space cooling demand divided by the a
...

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