ASTM F2474-14
(Test Method)Standard Test Method for Heat Gain to Space Performance of Commercial Kitchen Ventilation/Appliance Systems
Standard Test Method for Heat Gain to Space Performance of Commercial Kitchen Ventilation/Appliance Systems
SIGNIFICANCE AND USE
5.1 Heat Gain to Space—This test method determines the heat gain to the space from a hood/appliance system.
Note 2: To maintain a constant temperature in the conditioned space, this heat gain must be matched by space cooling. The space sensible cooling load, in tons, then equals the heat gain in Btu/h divided by the conversion factor of 12 000 Btu/h (3.412 W) per ton of cooling. Appliance heat gain data can be used for sizing air conditioning systems. Details of load calculation procedures can be found in ASHRAE, see Ref (1) and Ref (2)5. The calculation of associated cooling loads from heat gains to the test space at various flow rates can be used along with other information by heating, ventilation, air conditioning (HVAC), and exhaust system designers to achieve energy-conservative, integrated kitchen ventilation system designs.
5.2 Parametric Studies:
5.2.1 This test method also can be used to conduct parametric studies of alternative configurations of hoods, appliances, and replacement air systems. In general, these studies are conducted by holding constant all configuration and operational variables except the variable of interest. This test method, therefore, can be used to evaluate the following:
5.2.1.1 The overall system performance with various appliances, while holding the hood and replacement air system characteristics constant.
5.2.2 Entire hoods or characteristics of a single hood, such as end panels, can be varied with appliances and replacement air constant.
5.2.3 Replacement air characteristics, such as makeup air location, direction, and volume, can be varied with constant appliance and hood variables.
SCOPE
1.1 This test method covers the determination of appliance heat gain to space derived from the measurement and calculation of appliance energy consumption, energy exhausted, and energy to food, based on a system energy balance, parametric evaluation of operational or design variations in appliances, hoods, or replacement air configurations.
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
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Designation: F2474 − 14 An American National Standard
Standard Test Method for
Heat Gain to Space Performance of Commercial Kitchen
Ventilation/Appliance Systems
This standard is issued under the fixed designation F2474; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2.3 ANSI Standards:
ANSI/ASHRAE 51 and ANSI/AMCA 210 Laboratory
1.1 This test method covers the determination of appliance
Method of Testing Fans for Rating
heat gain to space derived from the measurement and calcula-
tion of appliance energy consumption, energy exhausted, and
NOTE 1—The replacement air and exhaust system terms and their
definitions are consistent with terminology used by theAmerican Society
energy to food, based on a system energy balance, parametric
of Heating, Refrigeration, and Air Conditioning Engineers. Where there
evaluation of operational or design variations in appliances,
are references to cooking appliances, an attempt has been made to be
hoods, or replacement air configurations.
consistent with terminology used in the test methods for commercial
cooking appliances. For each energy rate defined as follows, there is a
1.2 The values stated in inch-pound units are to be regarded
correspondingenergyconsumptionthatisequaltotheaverageenergyrate
as standard. The values given in parentheses are mathematical
multiplied by elapsed time. Electric energy and rates are expressed in W,
conversions to SI units that are provided for information only
kW, and kWh. Gas energy consumption quantities and rates are expressed
and are not considered standard.
in Btu, kBtu, and kBtu/h. Energy rates for natural gas-fueled appliances
are based on the higher heating value of natural gas.
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
3. Terminology
responsibility of the user of this standard to establish appro-
3.1 Definitions of Terms Specific to This Standard:
priate safety and health practices and determine the applica-
3.1.1 energy rate, n—average rate at which an appliance
bility of regulatory limitations prior to use.
consumes energy during a specified condition (for example,
idle or cooking).
2. Referenced Documents
3.1.2 appliance/hood energy balance, n—mathematical ex-
2.1 ASTM Standards:
pression of appliance, exhaust system, and food energy rela-
F1704Test Method for Capture and Containment Perfor-
tionship.
mance of Commercial Kitchen Exhaust Ventilation Sys-
tems
[actual appliance energy consumption]
= [heat gain to space from appliance(s)] + [energy exhausted] + [energy-to-
2.2 ASHRAE Standard:
food, if any]
ASHRAE Guideline 2-1986 (RA96)Engineering Analysis
3.1.3 cold start, n—condition in which appliances are ener-
of Experimental Data
gized with all components being at nominal room temperature.
ASHRAE Terminology of Heating, Ventilation, Air-
3.1.4 cooking energy consumption rate, n—average rate of
Conditioning, and Refrigeration
energy consumed by the appliance(s) during cooking specified
in appliance test methods.
This test method is under the jurisdiction of ASTM Committee F26 on Food
3.1.4.1 Discussion—In this test method, this rate is mea-
Service Equipment and is the direct responsibility of Subcommittee F26.07 on
suredforheavy-loadcookinginaccordancewiththeapplicable
Commercial Kitchen Ventilation.
Current edition approved Nov. 1, 2014. Published December 2014. Originally
test method.
approved in 2005. Last previous edition approved in 2009 as F2474–09. DOI:
3.1.5 exhaust energy rate, n—average rate at which energy
10.1520/F2474-14.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
is removed from the test system.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
Available from American Society of Heating, Refrigerating, and Air- 4th Floor, New York, NY 10036.
Conditioning Engineers, Inc. (ASHRAE), 1791 Tullie Circle, NE, Atlanta, GA The boldface numbers in parentheses refer to the list of references at the end
30329 of these test methods.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F2474 − 14
3.1.6 exhaust flow rate, n—volumetric flow of air (plus 3.1.15.1 Discussion—Radiant heat gain is not immediately
other gases and particulates) through the exhaust hood, mea- converted into cooling load. Radiant energy must first be
suredinstandardcubicfeetperminute,scfm(standardlitreper absorbed by surfaces that enclose the space and objects in the
second, sL/s). This also shall be expressed as scfm per linear space. As soon as these surfaces and objects become warmer
foot (sL/s per linear metre) of active exhaust hood length. than the space air, some of their heat is transferred to the air in
the space by convection. The composite heat storage capacity
3.1.7 energy-to-food rate, n—average rate at which energy
of these surfaces and objects determines the rate at which their
is transferred from the appliance to the food being cooked,
respective surface temperatures increase for a given radiant
using the cooking conditions specified in the applicable test
input and thus governs the relationship between the radiant
methods.
portion of heat gain and its corresponding part of the cooling
3.1.8 fanandcontrolenergyrate,n—averagerateofenergy
load. The thermal storage effect is critically important in
consumed by fans, controls, or other accessories associated
differentiating between instantaneous heat gain for a given
withcookingappliance(s).Thisenergyrateismeasuredduring
space and its cooling load for that moment.
preheat, idle, and cooking tests.
3.1.16 rated energy input rate, n—maximum or peak rate at
3.1.9 heat gain energy rate from appliance(s), n—average
which an appliance consumes energy as rated by the manufac-
rate at which energy is transferred from appliance(s) to the test
turer and specified on the appliance nameplate.
space around the appliance(s), exclusive of the energy ex-
3.1.17 replacement air, n—air deliberately supplied into the
hausted from the hood and the energy consumed by the food,
space (test room), and to the exhaust hood to compensate for
if any.
the air, vapor, and contaminants being expelled (typically
3.1.9.1 Discussion—This gain includes conductive,
referred to as makeup air).
convective, and radiant components. In conditions of complete
3.1.18 supply flow rate, n—volumetric flow of air supplied
capture, the predominant mechanism of heat gain consists of
to the exhaust hood in an airtight room, measured in standard
radiation from the appliance(s) and radiation from hood. In the
cubic feet per minute, scfm (standard litre per second, sL/s).
condition of hood spillage, heat is gained additionally by
This also shall be expressed as scfm per linear foot (sL/s per
convection.
linear metre) of active exhaust hood length.
3.1.10 hoodcaptureandcontainment,n—abilityofthehood
3.1.19 threshold of capture and containment, n—conditions
tocaptureandcontaingrease-ladencookingvapors,convective
of hood operation in which minimum flow rates are just
heat, and other products of cooking processes. Hood capture
sufficient to capture and contain the products generated by the
refers to the products getting into the hood reservoir from the
appliance(s). In this context, two minimum capture and con-
area under the hood while containment refers to the products
tainment points are determined, one for appliance idle
staying in the hood reservoir.
condition, and the other for heavy-load cooking condition.
3.1.11 idle energy consumption rate, n—average rate at
3.1.20 uncertainty, n—measure of the precision errors in
whichanapplianceconsumesenergywhileitisidling,holding,
specified instrumentation or the measure of the repeatability of
or ready-to-cook, at a temperature specified in the applicable
a reported result.
test method.
3.1.21 ventilation, n—that portion of supply air that is
3.1.12 latent heat gain, n—energy added to the test system
outdoor air plus any recirculated air that has been treated for
by the vaporization of liquids that remain in the vapor phase
the purpose of maintaining acceptable indoor air quality.
prior to being exhausted, for example, by vapor emitted by
products of combustion and cooking processes.
4. Summary of Test Method
3.1.13 makeup air handling hardware:—
4.1 Thistestmethodisusedtocharacterizetheperformance
3.1.13.1 diffuser, n—outlet discharging supply air in various
of commercial kitchen ventilation systems. Such systems
directions and planes.
include one or more exhaust-only hoods, one or more cooking
3.1.13.2 grille, n—covering for any opening through which
appliances under the hood(s), and a means of providing
air passes.
replacement (makeup) air. Ventilation system performance
includes the evaluation of the rate at which heat is transferred
3.1.13.3 register, n— grille equipped with a damper.
to the space.
3.1.13.4 throw, n—horizontal or vertical axial distance an
4.1.1 The heat gain from appliance(s) hood system is
air stream travels after leaving an air outlet before maximum
measured through energy balance measurements and calcula-
stream velocity is reduced to a specified terminal velocity, for
tions determined at specified hood exhaust flow rate(s). When
example, 100, 150, or 200 ft/min (0.51, 0.76, or 1.02 m/s).
heat gain is measured over a range of exhaust flow rates, the
3.1.14 measured energy input rate, n—maximum or peak
curve of energy gain to the test space versus exhaust rate
rate at which an appliance consumes energy measured during
reflects kitchen ventilation system performance, in terms of
appliance preheat, that is, measured during the period of
heat gain associated with the tested appliance(s).
operation when all gas burners or electric heating elements are
4.1.2 In the simplest case, under idle mode, energy ex-
set to the highest setting.
hausted from the test system is measured and subtracted from
3.1.15 radiant heat gain, n—fraction of the space energy theenergyintotheappliance(s)underthehood.Theremainder
gain provided by radiation. is heat gain to the test space. In the cooking mode, energy to
F2474 − 14
food also must be subtracted from appliance energy input to 6. Apparatus
calculate heat gain to space.
6.1 The general configuration and apparatus necessary to
4.1.3 Figs. 1-3 show sample curves for the theoretical view
perform this test method is shown schematically in Fig. 4 and
of heat gain due to hood spillage, an overall energy balance,
described in detail in Ref (3). Example test facilities are
and for heat gain versus exhaust flow rate for the general case.
described in Refs (4-6). The exhaust hood under test is
connected to an exhaust duct and fan and mounted in an
5. Significance and Use
airtightroom.Theexhaustfaniscontrolledbyavariablespeed
5.1 Heat Gain to Space—This test method determines the
drive to provide operation over a wide range of flow rates. A
heat gain to the space from a hood/appliance system.
complementary makeup air fan is controlled to balance the
exhaust rate, thereby maintaining a negligible static pressure
NOTE 2—To maintain a constant temperature in the conditioned space,
this heat gain must be matched by space cooling. The space sensible difference between the inside and outside of the test room.The
cooling load, in tons, then equals the heat gain in Btu/h divided by the
test facility includes the following:
conversionfactorof12000Btu/h(3.412W)pertonofcooling.Appliance
6.1.1 AirtightRoom,withsealableaccessdoor(s),tocontain
heat gain data can be used for sizing air conditioning systems. Details of
the exhaust hood to be tested, with specified cooking appli-
loadcalculationprocedurescanbefoundinASHRAE,seeRef (1)andRef
(2) .Thecalculationofassociatedcoolingloadsfromheatgainstothetest
ance(s) to be placed under the hood. The minimum volume of
space at various flow rates can be used along with other information by
the room shall be 6000 ft . The room air leakage shall not
heating,ventilation,airconditioning(HVAC),andexhaustsystemdesign-
exceed 20 scfm (9.4 sL/s) at 0.2 in. w.c. (49.8 Pa).
ers to achieve energy-conservative, integrated kitchen ventilation system
designs. 6.1.2 Exhaust and Replacement Air Fans, with variable-
speed drives, to allow for operation over a wide range of
5.2 Parametric Studies:
exhaust airflow rates.
5.2.1 Thistestmethodalsocanbeusedtoconductparamet-
6.1.3 Control System and Sensors, to provide for automatic
ric studies of alternative configurations of hoods, appliances,
or manual adjustment of replacement air flow rate, relative to
and replacement air systems. In general, these studies are
exhaustflowrate,toyieldadifferentialstaticpressurebetween
conducted by holding constant all configuration and opera-
inside and outside of the airtight room not to exceed 0.05 in.
tional variables except the variable of interest. This test
w.c. (12.5 Pa).
method, therefore, can be used to evaluate the following:
5.2.1.1 The overall system performance with various
6.1.4 Air Flow Measurement System Laminar Flow
appliances, while holding the hood and replacement air system
Element, AMCA 210 or equivalent nozzle chamber, mounted
characteristics constant.
in the replacement or exhaust airstream, to measure airflow
5.2.2 Entire hoods or characteristics of a single hood, such
rate.
as end panels, can be varied with appliances and replacement
NOTE 3—Because of potential problems with measurement in the hot,
air constant.
possibly grease-laden exhaust air stream, exhaust airflow rate can be
5.2.3 Replacement air characteristics, such as makeup air
determined by measuring the replacement airflow rate on the supply side.
location, direction, and volume, can be varied with constant
This requires the design of an airtight test facility that ensures the supply
rateequalstheexhaustratesinceairleakageoutsidethesystemboundary,
appliance and hood variables.
FIG. 1 Theoretical View of Heat Gain—Convective/Radiant Split
F2474 − 14
FIG. 2 Overall Energy Balance—Idle Condition
FIG. 3 Heat Gain Curve—Typical
thatis,allcomponentsbetweensupplyandexhaustblowersmakingupthe
7. Reagents and Materials
system, is negligible.
7.1 WaterandTestFoodProducts—Usewaterandtestfood
NOTE 4—Laminar flow elements have been used as an equivalent
alte
...
This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: F2474 − 09 F2474 − 14 An American National Standard
Standard Test Method for
Heat Gain to Space Performance of Commercial Kitchen
Ventilation/Appliance Systems
This standard is issued under the fixed designation F2474; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method covers the determination of appliance heat gain to space derived from the measurement and calculation
of appliance energy consumption, energy exhausted, and energy to food, based on a system energy balance, parametric evaluation
of operational or design variations in appliances, hoods, or replacement air configurations.
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2.1 ASTM Standards:
F1275 Test Method for Performance of Griddles
F1361 Test Method for Performance of Open Deep Fat Fryers
F1484 Test Methods for Performance of Steam Cookers
F1496 Test Method for Performance of Convection Ovens
F1521 Test Methods for Performance of Range Tops
F1605 Test Method for Performance of Double-Sided Griddles
F1639 Test Method for Performance of Combination Ovens (Withdrawn 2012)
F1695 Test Method for Performance of Underfired Broilers
F1704 Test Method for Capture and Containment Performance of Commercial Kitchen Exhaust Ventilation Systems
F1784 Test Method for Performance of a Pasta Cooker
F1785 Test Method for Performance of Steam Kettles
F1787 Test Method for Performance of Rotisserie Ovens
F1817 Test Method for Performance of Conveyor Ovens
F1991 Test Method for Performance of Chinese (Wok) Ranges
F1964 Test Method for Performance of Pressure Fryers
F1965 Test Method for Performance of Deck Ovens
F2093 Test Method for Performance of Rack Ovens
F2144 Test Method for Performance of Large Open Vat Fryers
F2237 Test Method for Performance of Upright Overfired Broilers
F2239 Test Method for Performance of Conveyor Broilers
2.2 ASHRAE Standard:
ASHRAE Guideline 2-1986 (RA96) Engineering Analysis of Experimental Data
ASHRAE Terminology of Heating, Ventilation, Air-Conditioning, and Refrigeration
This test method is under the jurisdiction of ASTM Committee F26 on Food Service Equipment and is the direct responsibility of Subcommittee F26.07 on Commercial
Kitchen Ventilation.
Current edition approved Oct. 1, 2009Nov. 1, 2014. Published November 2009December 2014. Originally approved in 2005. Last previous edition approved in 20052009
as F2474 – 05.F2474 – 09. DOI: 10.1520/F2474-09.10.1520/F2474-14.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Available from American Society of Heating, Refrigerating, and Air-Conditioning Engineers, Inc. (ASHRAE), 1791 Tullie Circle, NE, Atlanta, GA 30329
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F2474 − 14
2.3 ANSI Standards:
ANSI/ASHRAE 51 and ANSI/AMCA 210 Laboratory Method of Testing Fans for Rating
NOTE 1—The replacement air and exhaust system terms and their definitions are consistent with terminology used by the American Society of Heating,
Refrigeration, and Air Conditioning Engineers. Where there are references to cooking appliances, an attempt has been made to be consistent with
terminology used in the test methods for commercial cooking appliances. For each energy rate defined as follows, there is a corresponding energy
consumption that is equal to the average energy rate multiplied by elapsed time. Electric energy and rates are expressed in W, kW, and kWh. Gas energy
consumption quantities and rates are expressed in Btu, kBtu, and kBtu/h. Energy rates for natural gas-fueled appliances are based on the higher heating
value of natural gas.
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 energy rate, n—average rate at which an appliance consumes energy during a specified condition (for example, idle or
cooking).
3.1.2 appliance/hood energy balance, n—mathematical expression of appliance, exhaust system, and food energy relationship.
[actual appliance energy consumption]
= [heat gain to space from appliance(s)] + [energy exhausted] + [energy-to-
food, if any]
3.1.3 cold start, n—condition in which appliances are energized with all components being at nominal room temperature.
3.1.4 cooking energy consumption rate, n—average rate of energy consumed by the appliance(s) during cooking specified in
appliance test methods in methods.2.1.
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036.
The boldface numbers in parentheses refer to the list of references at the end of these test methods.
3.1.4.1 Discussion—
In this test method, this rate is measured for heavy-load cooking in accordance with the applicable test method.
3.1.5 exhaust energy rate, n—average rate at which energy is removed from the test system.
3.1.6 exhaust flow rate, n—volumetric flow of air (plus other gases and particulates) through the exhaust hood, measured in
standard cubic feet per minute, scfm (standard litre per second, sL/s). This also shall be expressed as scfm per linear foot (sL/s
per linear metre) of active exhaust hood length.
3.1.7 energy-to-food rate, n—average rate at which energy is transferred from the appliance to the food being cooked, using the
cooking conditions specified in the applicable test methods.
3.1.8 fan and control energy rate, n—average rate of energy consumed by fans, controls, or other accessories associated with
cooking appliance(s). This energy rate is measured during preheat, idle, and cooking tests.
3.1.9 heat gain energy rate from appliance(s), n—average rate at which energy is transferred from appliance(s) to the test space
around the appliance(s), exclusive of the energy exhausted from the hood and the energy consumed by the food, if any.
3.1.9.1 Discussion—
This gain includes conductive, convective, and radiant components. In conditions of complete capture, the predominant mechanism
of heat gain consists of radiation from the appliance(s) and radiation from hood. In the condition of hood spillage, heat is gained
additionally by convection.
3.1.10 hood capture and containment, n—ability of the hood to capture and contain grease-laden cooking vapors, convective
heat, and other products of cooking processes. Hood capture refers to the products getting into the hood reservoir from the area
under the hood while containment refers to the products staying in the hood reservoir.
3.1.11 idle energy consumption rate, n—average rate at which an appliance consumes energy while it is idling, holding, or
ready-to-cook, at a temperature specified in the applicable test method from method.2.1.
3.1.12 latent heat gain, n—energy added to the test system by the vaporization of liquids that remain in the vapor phase prior
to being exhausted, for example, by vapor emitted by products of combustion and cooking processes.
3.1.13 makeup air handling hardware:—
3.1.13.1 diffuser, n—outlet discharging supply air in various directions and planes.
3.1.13.2 grille, n—covering for any opening through which air passes.
3.1.13.3 register, n— grille equipped with a damper.
F2474 − 14
3.1.13.4 throw, n—horizontal or vertical axial distance an air stream travels after leaving an air outlet before maximum stream
velocity is reduced to a specified terminal velocity, for example, 100, 150, or 200 ft/min (0.51, 0.76, or 1.02 m/s).
3.1.14 measured energy input rate, n—maximum or peak rate at which an appliance consumes energy measured during
appliance preheat, that is, measured during the period of operation when all gas burners or electric heating elements are set to the
highest setting.
3.1.15 radiant heat gain, n—fraction of the space energy gain provided by radiation.
3.1.15.1 Discussion—
Radiant heat gain is not immediately converted into cooling load. Radiant energy must first be absorbed by surfaces that enclose
the space and objects in the space. As soon as these surfaces and objects become warmer than the space air, some of their heat
is transferred to the air in the space by convection. The composite heat storage capacity of these surfaces and objects determines
the rate at which their respective surface temperatures increase for a given radiant input and thus governs the relationship between
the radiant portion of heat gain and its corresponding part of the cooling load. The thermal storage effect is critically important
in differentiating between instantaneous heat gain for a given space and its cooling load for that moment.
3.1.16 rated energy input rate, n—maximum or peak rate at which an appliance consumes energy as rated by the manufacturer
and specified on the appliance nameplate.
3.1.17 replacement air, n—air deliberately supplied into the space (test room), and to the exhaust hood to compensate for the
air, vapor, and contaminants being expelled (typically referred to as makeup air).
3.1.18 supply flow rate, n—volumetric flow of air supplied to the exhaust hood in an airtight room, measured in standard cubic
feet per minute, scfm (standard litre per second, sL/s). This also shall be expressed as scfm per linear foot (sL/s per linear metre)
of active exhaust hood length.
3.1.19 threshold of capture and containment, n—conditions of hood operation in which minimum flow rates are just sufficient
to capture and contain the products generated by the appliance(s). In this context, two minimum capture and containment points
are determined, one for appliance idle condition, and the other for heavy-load cooking condition.
3.1.20 uncertainty, n—measure of the precision errors in specified instrumentation or the measure of the repeatability of a
reported result.
3.1.21 ventilation, n—that portion of supply air that is outdoor air plus any recirculated air that has been treated for the purpose
of maintaining acceptable indoor air quality.
4. Summary of Test Method
4.1 This test method is used to characterize the performance of commercial kitchen ventilation systems. Such systems include
one or more exhaust-only hoods, one or more cooking appliances under the hood(s), and a means of providing replacement
(makeup) air. Ventilation system performance includes the evaluation of the rate at which heat is transferred to the space.
4.1.1 The heat gain from appliance(s) hood system is measured through energy balance measurements and calculations
determined at specified hood exhaust flow rate(s). When heat gain is measured over a range of exhaust flow rates, the curve of
energy gain to the test space versus exhaust rate reflects kitchen ventilation system performance, in terms of heat gain associated
with the tested appliance(s).
4.1.2 In the simplest case, under idle mode, energy exhausted from the test system is measured and subtracted from the energy
into the appliance(s) under the hood. The remainder is heat gain to the test space. In the cooking mode, energy to food also must
be subtracted from appliance energy input to calculate heat gain to space.
4.1.3 Figs. 1-3 show sample curves for the theoretical view of heat gain due to hood spillage, an overall energy balance, and
for heat gain versus exhaust flow rate for the general case.
5. Significance and Use
5.1 Heat Gain to Space—This test method determines the heat gain to the space from a hood/appliance system.
NOTE 2—To maintain a constant temperature in the conditioned space, this heat gain must be matched by space cooling. The space sensible cooling
load, in tons, then equals the heat gain in Btu/h divided by the conversion factor of 12 000 Btu/h (3.412 W) per ton of cooling. Appliance heat gain data
can be used for sizing air conditioning systems. Details of load calculation procedures can be found in ASHRAE, see Ref (1) and Ref (2) . The calculation
of associated cooling loads from heat gains to the test space at various flow rates can be used along with other information by heating, ventilation, air
conditioning (HVAC), and exhaust system designers to achieve energy-conservative, integrated kitchen ventilation system designs.
5.2 Parametric Studies:
5.2.1 This test method also can be used to conduct parametric studies of alternative configurations of hoods, appliances, and
replacement air systems. In general, these studies are conducted by holding constant all configuration and operational variables
except the variable of interest. This test method, therefore, can be used to evaluate the following:
F2474 − 14
FIG. 1 Theoretical View of Heat Gain—Convective/Radiant Split
FIG. 2 Overall Energy Balance—Idle Condition
5.2.1.1 The overall system performance with various appliances, while holding the hood and replacement air system
characteristics constant.
5.2.2 Entire hoods or characteristics of a single hood, such as end panels, can be varied with appliances and replacement air
constant.
5.2.3 Replacement air characteristics, such as makeup air location, direction, and volume, can be varied with constant appliance
and hood variables.
6. Apparatus
6.1 The general configuration and apparatus necessary to perform this test method is shown schematically in Fig. 4 and
described in detail in Ref (3). Example test facilities are described in Refs (4-6). The exhaust hood under test is connected to an
exhaust duct and fan and mounted in an airtight room. The exhaust fan is controlled by a variable speed drive to provide operation
over a wide range of flow rates. A complementary makeup air fan is controlled to balance the exhaust rate, thereby maintaining
a negligible static pressure difference betw
...
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