ASTM F2093-18(2023)

Standard Test Method for Performance of Rack Ovens

SIGNIFICANCE AND USE
5.1 The energy input rate and thermostat calibration tests are used to confirm that the rack oven is operating properly prior to further testing.  
5.2 Preheat energy and time can be useful to food service operators to manage energy demands and to know how quickly the rack oven can be ready for operation.  
5.3 Idle energy rate and pilot energy rate can be used by the food service operator to estimate energy consumption during non-baking periods.  
5.4 The oven's browning and baking uniformity can be used by an operator to select an oven that bakes a variety of products evenly.  
5.5 Steam performance can be useful for a food service operator interested in the oven's ability to consistently create steam during a baking cycle.  
5.6 Baking energy efficiency is a precise indicator of rack oven energy performance under various loading conditions. This information enables the food service operator to consider energy performance when selecting a rack oven.  
5.7 Production capacity is used by food service operators to choose a rack oven that matches their food output requirements.
SCOPE
1.1 This test method evaluates the energy consumption and baking performance of rack ovens. The food service operator can use this evaluation to select a rack oven and understand its energy performance.  
1.2 This test method is applicable to thermostatically controlled, gas and electric rack ovens.  
1.3 The rack oven can be evaluated with respect to the following (where applicable):  
1.3.1 Energy input rate (10.2),  
1.3.2 Thermostat calibration (10.3),  
1.3.3 Preheat energy and time (10.4),  
1.3.4 Idle energy rate (10.5),  
1.3.5 Pilot energy rate, if applicable (10.6),  
1.3.6 White sheet cake browning (10.7), and  
1.3.7 Steam performance (10.8), and  
1.3.8 Baking energy efficiency and production capacity (10.9).  
1.4 The values stated in inch-pound units are to be regarded as standard.  
1.5 This test method may involve hazardous materials, operations, and equipment. 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-May-2023
• ICS: 97.040.20 - Cooking ranges, working tables, ovens and similar appliances
• Technical Committee: F26 - Food Service Equipment
• Drafting Committee: F26.06 - Productivity and Energy Protocol

Relations

• Refers: ASTM F1496-13(2019) - Standard Test Method for Performance of Convection Ovens
• Effective Date: 01-May-2019
• Refers: ASTM F1496-13 - Standard Test Method for Performance of Convection Ovens
• Effective Date: 01-Jun-2013
• Refers: ASTM F1496-12 - Standard Test Method for Performance of Convection Ovens
• Effective Date: 01-Oct-2012
• Refers: ASTM D3588-98(2011) - Standard Practice for Calculating Heat Value, Compressibility Factor, and Relative Density of Gaseous Fuels
• Effective Date: 01-Nov-2011
• Refers: ASTM F1496-99(2005)e1 - Standard Test Method for Performance of Convection Ovens
• Effective Date: 01-Oct-2005
• Refers: ASTM F1496-99(2005) - Standard Test Method for Performance of Convection Ovens
• Effective Date: 01-Oct-2005
• Refers: ASTM D3588-98(2003) - Standard Practice for Calculating Heat Value, Compressibility Factor, and Relative Density of Gaseous Fuels
• Effective Date: 10-May-2003
• Refers: ASTM F1496-99 - Standard Test Method for Performance of Convection Ovens
• Effective Date: 10-Oct-1999
• Refers: ASTM D3588-98 - Standard Practice for Calculating Heat Value, Compressibility Factor, and Relative Density of Gaseous Fuels
• Effective Date: 10-May-1998

Overview

ASTM F2093-18(2023) - Standard Test Method for Performance of Rack Ovens specifies a comprehensive methodology for evaluating the energy consumption and baking performance of rack ovens. Developed by ASTM International, this standard helps food service operators make informed decisions when selecting gas or electric, thermostatically controlled rack ovens. The test method covers aspects such as energy input rate, thermostat calibration, preheat parameters, idle and pilot energy rates, baking uniformity, steam performance, and overall baking efficiency.

Key Topics

• Energy Input and Thermostat Calibration: Verifies rack oven operation before performance tests, ensuring accurate energy consumption measurements.
• Preheat Energy and Time: Measures how quickly the oven reaches operating temperature, critical for energy management and workplace efficiency.
• Idle and Pilot Energy Rates: Assesses energy use during standby periods, aiding in estimating non-baking energy consumption.
• Browning and Baking Uniformity: Evaluates consistent baking and product quality across varying loads, including uniform browning of baked goods.
• Steam Performance: Examines the oven’s capability to generate steam, important for specific baking processes.
• Baking Energy Efficiency: Calculates energy effectiveness under varied load conditions, providing a key metric for energy-conscious purchasing.
• Production Capacity: Determines the maximum rate of food output, helping operators match equipment to production requirements.
• Safety and Environmental Considerations: Emphasizes the need for proper safety, health, and environmental practices during testing.

Applications

The ASTM F2093-18(2023) test method is invaluable for:

• Food Service Operators: Enables comparison of rack oven models based on energy efficiency, preheat performance, and output capacity, supporting informed equipment investments.
• Equipment Manufacturers: Offers a standardized framework for demonstrating the energy and performance characteristics of rack ovens to customers.
• Facility Managers: Assists in estimating operating costs through data on idle and pilot energy usage, and informs energy management strategies.
• Baking Professionals: Ensures that selected ovens meet requirements for product browning, uniformity, and steam generation-factors directly affecting product quality.
• Sustainability Initiatives: By quantifying baking energy efficiency, the standard supports selection of more energy-efficient commercial kitchen equipment, reducing overall facility energy consumption.

Related Standards

The ASTM F2093-18(2023) standard is designed with compatibility and reference to other established methods and guidelines, including:

• ASTM D3588: Practice for Calculating Heat Value, Compressibility Factor, and Relative Density of Gaseous Fuels.
• ASTM F1496: Test Method for Performance of Convection Ovens.
• ANSI Z83.11: American National Standard for Gas Food Service Equipment.
• ASHRAE Fundamentals and Guideline 2: Benchmarking for experimental data analysis and technical procedures.

These related standards ensure comprehensive and internationally recognized methodologies are maintained in testing for rack oven performance and energy efficiency.

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Keywords: ASTM F2093-18(2023), rack oven, energy efficiency, baking performance, oven testing, food service equipment, browning uniformity, steam performance, production capacity, energy input rate, thermostat calibration.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: F2093 − 18 (Reapproved 2023) An American National Standard
Standard Test Method for
Performance of Rack Ovens
This standard is issued under the fixed designation F2093; 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 2. Referenced Documents
2.1 ASTM Standards:
1.1 This test method evaluates the energy consumption and
D3588 Practice for Calculating Heat Value, Compressibility
baking performance of rack ovens. The food service operator
Factor, and Relative Density of Gaseous Fuels
can use this evaluation to select a rack oven and understand its
F1496 Test Method for Performance of Convection Ovens
energy performance.
2.2 ANSI Document:
1.2 This test method is applicable to thermostatically
ANSI Z83.11 American National Standard for Gas Food
controlled, gas and electric rack ovens.
Service Equipment
1.3 The rack oven can be evaluated with respect to the 2.3 ASHRAE Documents:
following (where applicable): ASHRAE Fundamentals 1997
ASHRAE Guideline 2-1986 (RA90) Engineering Analysis
1.3.1 Energy input rate (10.2),
of Experimental Data
1.3.2 Thermostat calibration (10.3),
1.3.3 Preheat energy and time (10.4),
3. Terminology
1.3.4 Idle energy rate (10.5),
3.1 Definitions of Terms Specific to This Standard:
1.3.5 Pilot energy rate, if applicable (10.6),
3.1.1 bake time, n—time required to bake the frozen pies
1.3.6 White sheet cake browning (10.7), and
specified in 7.3.
1.3.7 Steam performance (10.8), and
3.1.2 baking cavity, n—that portion of the appliance in
1.3.8 Baking energy efficiency and production capacity
which food products are heated or cooked.
(10.9).
3.1.3 baking energy, n—energy consumed by the rack oven
as it is used to bake frozen pies under full-load conditions.
1.4 The values stated in inch-pound units are to be regarded
as standard.
3.1.4 baking energy effıciency, n—quantity of energy im-
parted to the pies, expressed as a percentage of energy
1.5 This test method may involve hazardous materials,
consumed by the rack oven during the baking event.
operations, and equipment. This standard does not purport to
3.1.5 baking energy rate, n—average rate of energy con-
address all of the safety concerns, if any, associated with its
sumption (Btu/h or kW) during the baking energy efficiency
use. It is the responsibility of the user of this standard to
tests.
establish appropriate safety, health, and environmental prac-
tices and determine the applicability of regulatory limitations
3.1.6 duty cycle, n—defined as percent (%) of burner time
prior to use.
on divided by a complete on/off cycle during idle energy mode
1.6 This international standard was developed in accor- at 400°F.
dance with internationally recognized principles on standard-
3.1.7 idle energy rate, n—the rate of energy consumed
ization established in the Decision on Principles for the
(Btu/h or kW) by the rack oven while “holding” or “idling” the
Development of International Standards, Guides and Recom-
baking cavity at the thermostat set point.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
This test method is under the jurisdiction of ASTM Committee F26 on Food the ASTM website.
Service Equipment and is the direct responsibility of Subcommittee F26.06 on Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
Productivity and Energy Protocol. 4th Floor, New York, NY 10036, http://www.ansi.org.
Current edition approved June 1, 2023. Published July 2023. Originally approved Available from American Society of Heating, Refrigerating, and Air-
in 2001. Last previous edition approved in 2018 as F2093 – 18. DOI: 10.1520/ Conditioning Engineers, Inc. (ASHRAE), 1791 Tullie Circle, NE, Atlanta, GA
F2093-18R23. 30329, http://www.ashrae.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F2093 − 18 (2023)
3.1.8 measured energy input rate, n—peak rate at which a and 30 cakes in a double-rack oven, for example) to assess the
rack oven consumes energy (Btu/h or kW), typically reflected browning uniformity of the oven.
during preheat.
4.7 The rack oven’s steam performance is characterized by
3.1.9 mini-rack oven, n—an appliance that bakes by forcing
assessing the amount of steam produced on repeated bake
air within a closed cavity, either fitted with a mechanism for cycles.
rotating an internal rack which accomodates 8 pans at 4 in.
4.8 The rack oven is used to bake a full-load of frozen pies.
spacing or a fixed 8 pans at 4 in. spacing within the cavity.
Baking energy efficiency, baking energy rate, and production
3.1.10 nameplate energy input rate, n—the maximum or
rate are determined from these tests.
peak rate at which an appliance consumes energy as rated by
5. Significance and Use
the manufacturer and specified on the nameplate.
5.1 The energy input rate and thermostat calibration tests
3.1.11 pilot energy rate, n—average rate of energy con-
are used to confirm that the rack oven is operating properly
sumption (Btu/h) by a rack oven’s continuous pilot (if appli-
prior to further testing.
cable).
3.1.12 preheat energy, n—amount of energy consumed by 5.2 Preheat energy and time can be useful to food service
the rack oven while preheating the baking cavity from ambient operators to manage energy demands and to know how quickly
room temperature (75 6 5°F) to the thermostat set point. the rack oven can be ready for operation.
3.1.13 preheat rate, n—average rate (°F/min) at which the
5.3 Idle energy rate and pilot energy rate can be used by the
rack oven’s baking cavity is heated from ambient temperature food service operator to estimate energy consumption during
(75 6 5°F) to the thermostat set point: defined as the set
non-baking periods.
temperature minus ambient temperature divided by the preheat
5.4 The oven’s browning and baking uniformity can be used
time.
by an operator to select an oven that bakes a variety of products
3.1.14 preheat time, n—time required for the rack oven to
evenly.
preheat from ambient room temperature (75 6 5°F) to the
5.5 Steam performance can be useful for a food service
thermostat set point.
operator interested in the oven’s ability to consistently create
3.1.15 production capacity, n—maximum rate (lb/h) at
steam during a baking cycle.
which the rack oven can bake frozen pies as specified in 7.3.
5.6 Baking energy efficiency is a precise indicator of rack
3.1.16 rack, n—a device which is used to hold pans within
oven energy performance under various loading conditions.
a rack oven.
This information enables the food service operator to consider
energy performance when selecting a rack oven.
3.1.17 rack oven, n—an appliance that bakes by forcing hot
air over the food within a closed cavity, either fitted with a
5.7 Production capacity is used by food service operators to
mechanism for rotating one or more racks, or one or more
choose a rack oven that matches their food output require-
non-rotating racks within the cavity.
ments.
3.1.18 steam injection cycle, n—a period whereby steam is
6. Apparatus
introduced into the baking cavity during baking.
6.1 Analytical Balance Scale, for measuring weights up to
3.1.19 uncertainty, n—measure of systematic and precision
25 lb, with a resolution of 0.01 lb and an uncertainty of 0.01 lb.
errors in specified instrumentation or measure of repeatability
of a reported test result. 6.2 Barometer, for measuring absolute atmospheric
pressure, to be used for adjustment of measured gas volume to
4. Summary of Test Method standard conditions. Shall have a resolution of 0.2 in. Hg and
an uncertainty of 0.2 in. Hg.
4.1 The rack oven is connected to the appropriate metered
energy source, and energy input rate is determined to confirm 6.3 Data Acquisition System, for measuring energy and
temperatures, capable of multiple channel displays updating at
that the appliance is operating within 5 % of the nameplate
energy input rate. least every 2 s.
6.4 Freezer, sized large enough to hold a full-load of frozen
4.2 The accuracy of the oven’s thermostat is checked at
pies (24 pies for a mini-rack oven, 45 pies for a single rack
400°F and adjusted as necessary.
oven, and 90 pies for a double rack oven) and capable of
4.3 The amount of energy and time required to preheat the
maintaining the frozen product at 0 6 5°F.
rack oven to 400°F is determined.
6.5 Flow Meter, for measuring total water consumption of
4.4 The idle energy rate is determined with the rack oven set
the oven, having a resolution of 0.01 gal and an uncertainty of
to maintain 400°F in the baking cavity.
0.01 gal for flows of 0.2 gpm and higher.
4.5 Pilot energy rate is determined, when applicable, for gas
6.6 Gas Meter, for measuring the gas consumption of a rack
rack ovens.
oven, shall be a positive displacement type with a resolution of
4.6 The rack oven is used to bake a full-load of white sheet at least 0.1 ft and a maximum uncertainty no greater than 1 %
cakes (8 cakes in a mini-rack, 15 cakes in a single-rack oven, of the measured value for any demand greater than 2.2 ft /h. If
F2093 − 18 (2023)
product for testing by Pacific Gas and Electric Company.
the meter is used for measuring the gas consumed by the pilot
lights, it shall have a resolution of at least 0.1 ft and a
7.4 Hotel Pan, to be used to collect water runoff during
maximum uncertainty no greater than 2 % of the measured
testing.
value.
7.5 Paper Baking Liners, to line sheet pans for browning
6.7 Heavy-Duty Chef’s Thermometers, capable of with-
uniformity tests.
standing 400°F temperatures for monitoring food temperature
7.6 Plastic Wrap, commercial grade, 18-in. wide.
while baking. A 2-in. or larger dial is recommended for
7.7 Rack, supplied by the oven manufacturer shall have a
enhanced visibility.
nominal 4-in. spacing between pan positions, with a minimum
6.8 Platform Balance Scale, or appropriate load cells, for
of 4-in. between the top pan and the top of the top of the rack
measuring weights up to 500 lb with a resolution of 0.2 lb and
and a minimum of 4-in. between the bottom pan and the floor.
an uncertainty of 0.2 lb.
7.8 Water, supplied to the rack oven shall be 65 6 5°F. If
6.9 Pressure Gauge, for monitoring gas pressure. Shall have
outside this range, hot and cold water supplies may be mixed
a range of zero to 15 in. H O, a resolution of 0.5 in. H O, and
2 2
to achieve the required inlet temperature.
a maximum uncertainty of 3 % of the measured value.
6.10 Stop Watch, with a 1-s resolution. 8. Sampling, Test Units
6.11 Temperature Sensor, for measuring gas temperature in
8.1 Rack Oven—Select a representative production model
the range of 50 to 100°F with an uncertainty of 61°F. for performance testing.
6.12 Thermocouple(s), industry standard type K thermo-
9. Preparation of Apparatus
couple wire with a range of 0 to 600°F and an uncertainty of
9.1 Install the oven according to the manufacturer’s instruc-
61°F.
tions in an appropriate space. All sides of the oven shall be a
6.13 Thermocouple Probe, “fast response” type T or type K
minimum of 6-in. from any side wall, side partition, or other
thermocouple probe, ⁄16 in. or smaller diameter, with a 3 s or
operating appliance. The oven, moisture vent, and hood
faster response time, capable of immersion with a range of 30
assembly, as furnished, shall be vented to the exterior of the
to 300°F and an uncertainty of 61°F. The thermocouple
testing space, using the manufacturer’s specified ventilation
probe’s active zone shall be at the tip of the probe.
rate(s). The associated heating or cooling system for the space
6.14 Watt-Hour Meter, for measuring the electrical energy
shall be capable of maintaining an ambient temperature of 75
consumption of a rack oven, shall have a resolution of at least
6 5°F within the testing environment (outside the vertical area
10 Wh and a maximum uncertainty no greater than 1.5 % of the
of the rack oven) when the combined oven exhaust ventilation
measured value for any demand greater than 100 W. For any
system is operating.
demand less than 100 W, the meter shall have a resolution of at
9.2 Install a thermocouple at the vertical center of the
least 10 Wh and a maximum uncertainty no greater than 10 %.
oven’s pressure panel in the air outlet, with the sensing tip 1.0
6 0.25-in. away from the vertical plane of the panel to record
7. Reagents and Materials
the oven cavity temperature. Make certain that the thermo-
7.1 Aluminum Sheet Pans, measuring 18 by 26 by 1 in. for
couple sensing tip is not touching the pressure panel or any of
the baking energy efficiency and sheet cake browning tests.
its components.
7.2 Cake Mix, generic white cake mix, 5 lb per box. A
9.3 Adjust the air baffles inside the oven cavity to the
minimum of 30 lb is required for mini-rack ovens, 50 lb for
manufacturer’s recommended gap settings. Follow the manu-
single-rack ovens, and 100 lb for double-rack ovens.
facturer’s recommendation for fine adjustments.
7.3 Frozen Pies, 10-in. frozen, commercial-grade, ready-to-
9.4 Connect the rack oven to a calibrated energy test meter.
bake apple pies, weighing 3.00 6 0.15 lb, with a moisture
For gas installations, install a pressure regulator downstream
content of 54 6 2 %, by weight for baking energy efficiency
from the meter to maintain a constant pressure of gas for all
and production capacity tests. The pie crust shall be made with
tests. Install instrumentation to record both the pressure and
100 % vegetable shortening and the filling shall be a pre-
temperature of the gas supplied to the rack oven and the
cooked apple based filling (see Fig. 1).
barometric pressure during each test so that the measured gas
NOTE 1—Sysco Classic fruit pies have been shown to be an acceptable flow can be corrected to standard conditions. For electric
FIG. 1 Cross Section of a Frozen Apple Pie
F2093 − 18 (2023)
NOTE 3—A small length of PVC pipe has been found an effective tool
installations, a voltage regulator may be required during tests if
for fixing the probes and inserting them into the baked pies.
the voltage supply is not within 62.5 % of the manufacturer’s
nameplate voltage.
10. Procedure
9.5 For a gas rack oven, adjust (during maximum energy
10.1 General:
input) the gas supply pressure downstream from the appli-
10.1.1 For gas rack ovens, record the following for each test
ance’s pressure regulator to within 62.5 % of the operating
run:
manifold pressure specified by the manufacturer. Make adjust-
10.1.1.1 Higher heating value,
ments to the appliance following the manufacturer’s recom-
10.1.1.2 Standard gas pressure and temperature used to
mendations for optimizing combustion. Proper combustion
correct measured gas volume to standard conditions,
shall be verified by measuring air-free CO in accordance with
10.1.1.3 Measured gas temperature,
ANSI Z83.11.
10.1.1.4 Measured gas pressure,
9.6 For an electric rack oven, confirm (while the elements
10.1.1.5 Barometric pressure,
are energized) that the supply voltage is within 62.5 % of the
10.1.1.6 Ambient temperature, and
operating voltage specified by the manufacturer. Record the
10.1.1.7 Energy input rate during or immediately prior to
test voltage for each test.
test.
NOTE 2—It is the intent of the testing procedure herein to evaluate the
NOTE 4—Using a calorimeter or gas chromatograph in accordance with
performance of a rack oven at its rated gas pressure or electric voltage. If
accepted laboratory procedures is the preferred method for determining
an electric unit is rated dual voltage (this is, designed to operate at either
the higher heating value of gas supplied to the rack oven under test. It is
240 or 480 V with no change in components), the voltage selected by the
recommended that all testing be performed with natural gas having a
manufacturer and/or tester shall be reported. If a rack oven is designed to
higher heating value of 1000 to 1075 Btu/ft .
operate at two voltages without a change in the resistance of the heating
10.1.2 For gas rack ovens, record any electric energy
elements, the performance of the unit (for example, preheat time) may
consumption, in addition to gas energy for all tests.
differ at the two voltages.
10.1.3 For electric rack ovens, record the following for each
9.7 Install a flow meter to the rack oven water inlet such that
test run:
total water flow to the appliance is measured and a pressure
10.1.3.1 Voltage while elements are energized,
regulator downstream from the meter to maintain a constant
10.1.3.2 Ambient temperature, and
pressure of water for the steam performance tests. Also install
10.1.3.3 Energy input rate during or immediately prior to
a thermocouple probe in the inlet water line to the rack oven for
test run.
monitoring inlet water temperature.
10.1.4 For each test run, confirm that the peak input rate is
9.8 Adjust the water pressure to the manufacturer’s recom-
within 65 % of the rated nameplate input. If the difference is
mended operating water pressure.
greater than 5 %, terminate testing and contact the manufac-
9.9 Assure that the oven cavity vent is closed for all turer. The manufacturer may make appropriate changes or
adjustments to the rack oven.
tests—except as instructed by this procedure.
9.10 To facilitate quickly measuring baked pie 10.2 Energy Input Rate:
temperatures, fix three thermocouple probes along a straight 10.2.1 Set the temperature controls 400°F and turn on the
line, located 3 6 0.2 in. apart and configured with a mechanism oven.
for ensuring that they are inserted to 1 6 0.1-in. depth as 10.2.2 Start recording time and energy consumption when
shown in Fig. 2. the burners actually ignite or when the elements are energized
FIG. 2 Example Thermocouple Fixture for Measuring Pie Temperatures
F2093 − 18 (2023)
(not when the oven ready light comes on) and stop recording 10.5.6 At the end of the setback idle, preheat the oven back
when the burners or elements commence cycling. to 400°F and record time, energy, and starting and final
temperatures until the burners or elements cycle off.
10.2.3 Confirm that the measured input rate or power,
(Btu/h for a gas rack oven and kW for an electric rack oven) is
10.6 Pilot Energy Rate (Gas Models with Standing Pilots):
within 5 % of the rated nameplate input or power (it is the
10.6.1 Where applicable, set the gas valve that controls gas
intent of the testing procedures herein to evaluate the perfor-
supply to the appliance at the “pilot” position. Otherwise, set
mance of a rack oven at its rated energy input rate). If the
the rack oven temperature controls to the “off” position.
difference is greater than 5 %, terminate testing and contact the
10.6.2 Light and adjust pilots according to the manufactur-
manufacturer. The manufacturer may make appropriate
er’s instructions.
changes or adjustments to the rack oven or supply another rack
10.6.3 Record the gas reading after a minimum of 8 h of
oven for testing.
pilot operation.
10.3 Thermostat Calibration:
10.7 Browning Uniformity (White Sheet Cakes):
10.3.1 Preheat the baking cavity to a temperature of 400°F
NOTE 7—The objective of this test is to evaluate the browning
as indicated by the temperature control. Stabilize for 2 h after
uniformity of the oven using white sheet cakes. The oven’s browning
the burners or elements commence cycling at the thermostat set
uniformity is reported by describing the browning pattern of the sheet cake
point. baked on each rack. This test is to be performed so that the variation in
browning from rack to rack is minimized.
10.3.2 Monitor and record the cavity temperature every 30
s for a minimum of 1 h. 10.7.1 Preheat oven to 325°F and allow to stabilize for 2 h.
10.7.2 Mix cake batter per purveyor’s instructions. For
10.3.3 As required (as indicated by the average
mini-rack ovens, prepare a minimum of 45 lb of batter; for
temperature), calibrate or otherwise adjust the temperature
single-rack ovens, prepare a minimum of 75 lb of batter; and
control(s) to attain an actual baking cavity temperature of 400
for double-rack ovens, prepare a minimum of 150 lb of batter.
6 5°F. Repeat 10.3.2 to confirm that the cavity temperature is
10.7.3 Scale 5.0 6 0.01 lb of cake batter into each lined,
400 6 5°F.
pre-weighed sheet pan. Level the batter in each pan with a
10.4 Preheat Energy Consumption and Time:
spatula. Lightly drop each pan two to three times to reduce the
number of air bubbles in the batter.
NOTE 5—The preheat test should be conducted as the first appliance
operation on the day of the test, starting with the baking cavity at room
10.7.4 Load the filled sheet pans onto the rack(s). Use every
temperature (75 6 5°F).
pan position available (15 for single-racks and 30 for double-
racks; for mini-rack ovens a simple holding rack is required).
10.4.1 Record oven cavity temperature and ambient tem-
10.7.5 Record the starting temperature of every other cake.
perature at the start of the test. The cavity temperature shall be
10.7.6 When the oven cycles off, for mini-rack ovens load
75 6 5°F at the start of the test.
the pans (8 required) into the allotted location on the internal
10.4.2 Turn the unit on with controls set to maintain an
rack into the hot oven; for rack ovens, load the rack(s) into the
average cavity temperature of 400°F, as determined in 10.3.3.
hot oven. Loading time shall be 45 6 15 s. Begin monitoring
10.4.3 Record the cavity temperature at least once every 5 s
time, temperature, and energy consumption when the door is
during the course of preheat.
shut.
10.4.4 Record the energy and time to preheat the rack oven.
10.7.7 Test is complete when cakes have turned uniformly
Preheat is judged complete when the temperature at the
golden brown. Open door and remove the rack(s) within 45 6
pressure panel reaches 390°F, as indicated by the thermo-
15 s.
couple.
10.7.8 Determine whether the sheet cakes are done by first
inserting a skewer into the center of several cakes. The
10.5 Idle Energy Rate:
individual cake is considered done if no moist particles cling to
NOTE 6—The idle test may be conducted immediately following the
the skewer when it is withdrawn. Whether the cake load is done
preheat test (10.4).
properly, overdone, or underdone is determined by the color of
10.5.1 Preheat the rack oven to 400°F and allow to stabilize
the cakes. Refer to Fig. 3. If less than 60 % of the cakes are
for 2 h.
golden or darker in color, the cakes are underdone and the bake
time should be lengthened. If 60 % or more of the cakes are
10.5.2 Monitor baking cavity temperature and rack oven
energy consumption for an additional 3 h while the rack oven dark brown, the cakes are overdone and the bake time should
be shortened. If underdone or overdone, the browning unifor-
is operated in this condition. If the oven has a setback mode, it
must be disabled for the 3 h idle. mity cannot be determined.
10.7.9 If a bake time adjustment is required, repeat 10.7.2 –
10.5.3 If the oven has an automatic setback mode, record
10.7.8 until an acceptable level of doneness is achieved.
the amount of time in idle operation to trigger setback mode.
Record the final bake time.
10.5.4 Wait for the oven cavity temperature to drop and
10.7.10 Record the final temperature of every other cake
record the amount of time for the burner or heating element to
within 3 min 6 15 s of removing them from the oven.
start cycling in setback mode.
10.7.11 Record the final weight of each pan.
10.5.5 Start recording time, temperature and energy once
the oven starts to cycle in setback mode for 3 h. 10.8 Steam Performance:
F2093 − 18 (2023)
10.9.10 Measure and record the temperature of at least one
pie per pan by inserting a thermocouple probe into the
geometric center of the pie. This is best accomplished by
inserting the probe perpendicularly through the top of the pie.
Record the total weight of the rack(s), pies, and pans.
10.9.11 When the oven cycles off, for mini-rack ovens load
the pans into the appropriate location (8 pans) into the hot
oven; for rack ovens, load the rack(s) into the hot oven.
Loading time shall be 45 6 15 s. Begin monitoring time,
temperature, and energy consumption when the door is shut.
10.9.12 When the chef’s thermometers indicate that the pies
have reached an average temperature of 180°F, open the oven
door and measure the internal temperature of a randomly
chosen pie by inserting the 3-point thermocouple fixture into
FIG. 3 Color Browning Chart
the center of the pie, along the pie’s diameter.
10.9.12.1 If the average of the three temperatures is 185 6
5°F, the pies are done and may be removed.
10.9.12.2 If the temperature is below 180°F, close the door
NOTE 8—The objective of this test is to evaluate steam generation
and resume baking until the temperature of a randomly selected
capability on repeated bake cycles. Usage expectation is that a rack oven
pie is 185 6 5°F.
is ready for immediate use after removal of prior product. For simplicity,
10.9.12.3 If the temperature is above 190°F, then the pies
the test is performed with an empty oven.
are overcooked and the test is invalid. Adjust the bake time as
10.8.1 Preheat oven to 400°F and allow to stabilize for 2 h.
appropriate and repeat 10.9.2 – 10.9.11.
Set the steam induction timer to the manufacturer’s recom-
10.9.13 When the pies reach an average internal tempera-
mended interval. If the manufacturer does not specify a steam
ture of 185 6 5°F, open the oven door and remove the rack(s).
injection time, then set the timer to 10 s.
Unloading time shall be 45 6 15 s. Record the total elapsed
10.8.2 Record the initial weight of the empty runoff pan.
time and energy consumption.
10.8.3 Run the steam cycle, measuring the input water
10.9.14 After removing the racks, shut the oven door and
volume.
record the time and energy required to return the cavity to 400
10.8.4 Collect all runoff in the runoff pan and weigh the pan
6 5°F.
and accumulated runoff.
10.9.15 Record the temperature of at least one pie per every
10.8.5 Repeat 10.8.2 through 10.8.4 a total of five times at
pan by inserting the 3-point thermocouple rig into the center of
15 6 0.1-min intervals.
the pie, along the pie’s diameter, within 3 min 6 15 s from the
10.9 Baking Energy Effıciency and Production Capacity:
time the pies were removed from the oven. If the average of
10.9.1 Conduct the baking energy efficiency test a minimum
these temperatures is not 185 6 5°F, then the test is invalid and
of three times. Additional test runs may be necessary to obtain
must be repeated.
the required precision for the reported test results (Annex A1).
10.9.16 Record the final weight of the rack, pies, and pans.
10.9.2 Determine the number of pans required, use fifteen
10.9.17 Perform runs #2 and #3 by repeating 10.9.2 –
pans for single-racks and thirty pans for double-racks.
10.9.16. Follow the procedure in Annex A1 to determine
10.9.3 Weigh and record the weight of each sheet pan to be
whether more than three test runs are required.
used in the mini-rack ovens and the empty rack(s) and the lined
11. Calculation and Report
sheet pans for rack ovens.
10.9.4 Set aside at least two pies for determining moisture
11.1 Test Rack Oven:
content. Place sample pies in a freezer inside self-sealing
11.1.1 Summarize the physical and operating characteristics
plastic bags unless the moisture content determination test
of the rack oven, reporting all manufacturer’s specifications
(Annex A2) is conducted immediately.
and deviations therefrom. Include design characteristics, such
10.9.5 Return the loaded pans to the freezer and allow the
as integrated hoods, automatic steam vents, steam generation,
pies to stabilize at 0 6 5°F.
etc. Also report the ventilation rate used for the testing. Also
10.9.6 Preheat the oven to 400°F and allow to stabilize for
include the type of material and weight of the steam generator.
a minimum of 2 h.
11.2 Apparatus and Procedure:
10.9.7 Remove the frozen pies from their boxes and place
11.2.1 Confirm that the testing apparatus conformed to all of
three frozen pies per sheet pan.
the specifications in Section 6. Describe any deviations from
10.9.8 Load the rack(s) with the pie-filled sheet pans.
those specifications.
10.9.9 To facilitate determining when the pies are baked,
11.2.2 For electric rack ovens, report the voltage for each
randomly select four pies on different pans for monitoring and
test.
insert a heavy-duty chef’s thermometer into the center of the
11.2.3 For gas rack ovens, report the higher heating value of
chosen pies, making certain that the dials rest along the edge of
the gas supplied to the rack oven during each test.
each pie tin and are fully visible from the oven window during
baking. 11.3 Gas Energy Calculations:
F2093 − 18 (2023)
11.3.1 For gas rack ovens, add electric energy consumption 11.6 Preheat Energy and Time:
to gas energy for all tests, with the exception of the energy
11.6.1 Report the preheat energy consumption (Btu or kWh)
input rate test (section 10.2).
and air preheat time (min) to reach 390°F at the oven’s pressure
11.3.2 For all gas measurements, calculate the energy con-
panel with the controls set to a calibrated 400°F setting.
sumed based on:
11.6.2 Calculate and report the average air preheat rate
(°F/min) based on the preheat period. Also report the starting
E 5 V × HV (1)
gas
temperature of the baking cavity. This rate is:
where:
T 2 T / preheat time mins
~ ! ~ ~ !!
set room
E = energy consumed by the appliance,
gas
HV = higher heating value,
11.6.3 Generate a graph showing the baking cavity tempera-
= energy content of gas measured at standard
ture versus time based on the preheat period.
conditions, Btu/ft ,
11.7 Idle Energy Rate:
V = actual volume of gas corrected for temperature and
11.7.1 Calculate and report the idle energy rate (Btu/h or
pressure at standard conditions, ft ,
kW) at 400°F based on:
= V × T × P
meas cf cf
E × 60
where:
q 5 (3)
idle
t
V = measured volume of gas, ft
meas
T = temperature correction factor where:
cf
= absolute standard gas temperature °R / absolute
q = idle energy rate, Btu/h or kW,
idle
actual gas temperature °R
E = energy consumed during the test period, Btu or kWh,
= absolute standard gas temperature °R / [gas temp °F
and
+ 459.67] °R
t = test period, min.
P = pressure correction factor
cf
11.8 Pilot Energy Rate:
= absolute actual gas pressure psia / absolute standard
11.8.1 Calculate and report the pilot energy rate (Btu/h)
pressure psia
based on:
= gas gage pressure psig + barometric pressure psia ⁄
absolute standard pressure psia
E × 60
q 5 (4)
NOTE 9—Absolute standard gas temperature and pressure used in this pilot
t
calculation should be the same values used for determining the higher
heating value. Standard conditions using ASTM D3588-89 Standard
where:
Practice for Calculating Heat Value, Compressibility Factor, and Relative
q = pilot energy rate, Btu/h or kW,
pilot
Density (Specific Gravity) of Gaseous Fuels are 14.696 psia (101.33 kPA)
E = energy consumed during the test period, Btu, and
and 60°F (519.67 °R, (288.71 °K)).
t = test period, min.
11.4 Energy Input Rate:
11.9 Browning Uniformity (White Sheet Cakes):
11.4.1 Report the manufacturer’s nameplate energy input
rate in Btu/h for a gas rack oven and kW for an electric rack 11.9.1 Provide a written description of the browning pattern
oven. and any irregularities for each sheet cake. Also, note any
11.4.2 For gas or electric rack ovens, calculate and report differences in browning patterns and irregularities from cake to
the measured energy input rate (Btu/h or kW) based on the cake. A sketch or photograph of each cake showing its
energy consumed by the rack oven during the period of peak browning pattern and any irregularities shall accompany the
description. Use a scale of 1 to 5 (Fig. 3 Color Chart) with 3
energy input according to the following relationship:
being the ideal color.
E × 60
q 5 (2)
11.9.2 Report the cake load bake time and energy consump-
input
t
tion. Also report the initial and final weights and temperatures
where:
of the sheet cakes.
q = measured peak energy input rate, Btu/h or kW,
input
11.10 Steam Performance:
E = energy consumed during period of peak energy
11.10.1 For each steam injection cycle, calculate and report
input, Btu or kWh, and
the amount of steam produced based on:
t = period of peak energy input, min.
V 5 V 2 V (5)
steam water runoff
11.4.3 Calculate and report the percent difference between
the manufacturer’s nameplate energy input rate and the mea-
where:
sured energy input rate.
V = volume of steam produced, gal,
steam
11.5 Thermostat Calibration: V = volume of water consumed during the steam cycle,
water
gal,
11.5.1 For the as-received condition, report the oven cavity
V = volume of water collected in the runoff pan, gal,
temperature (at the pressure panel) that corresponds to the
runoff
= W – W / ρ
400°F setting on the oven’s thermostat control. runoff, i runoff, f water
11.5.2 Report any discrepancies greater than 5°F between
where:
the temperature indicated by the oven’s control and the 400°F
W = initial weight of runoff pan, lb,
runoff, i
oven cavity temperature.
F2093 − 18 (2023)
W = final weight of runoff pan, including any accu- E = the latent heat (of vaporization) added to the food,
runoff, f evap
mulated water, lb, and which causes some of the moisture contained in the
ρ = density of water, lb/gal, food to evaporate. The heat of vaporization cannot
water
= 8.334 lb/gal.
be perceived by a change in temperature and must be
calculated after determining the amount of moisture
11.10.2 For each of the five successive steam injection
lost from a fully baked pie,
cycles, report the volume of water consumed by the oven and
= (W – W ) × H
i f v
the volume of the runoff and the volume converted to steam as
determined in 11.10.1.
where:
11.11 Baking Energy Effıciency, Baking Energy Rate, and
W = the initial weight of the frozen pies, lb,
i
Production Capacity: W = the final weight of the baked pies, lb,
f
H = heat of vaporization, Btu/lb,
11.11.1 Calculate and report the baking energy efficiency
v
= 970 Btu/lb at 212°F,
based on:
E = energy into the sheet pans, Btu,
pans
E 1E
food pans
= W × C × (T – T )
η 5 × 100 (6) pans p, pans f i
cook
E
appliance
where:
where:
W = weight of sheet pans, lb,
pans
η = baking energy efficiency, %,
cook
C = specific heat of the sheet pans, Btu/lb,°F,
p, pans
E = energy into the food, Btu,
food
= 0.20
= E + E + E
sens thaw evap
T = final average internal temperature of the baked
f
pies, °F
where:
T = initial average internal temperature of the frozen
i
E = the quantity of heat added to the food, which causes
sens
pies, °F, and
its temperature to increase from the starting tempera-
E = energy into the appliance, Btu.
appliance
ture to the final cooked temperature, Btu,
NOTE 11—The energy into the appliance includes electric energy
= W × C × (T – T )
i p, pie f i
consumed by fans, motors, and controls.
where:
11.11.2 Calculate and report the baking energy rate based
W = initial weight of the frozen pies, lb, on:
i
C = specific heat of the apple pies, Btu/lb,°F
p, pie
E × 60
= 0.63 E 5 (7)
bake rate
t
NOTE 10—For this analysis, the specific heat (C ) of an apple pie is
p, pie
considered to be the weighted average of the specific heat of its
where:
components (for example, water, fat, and nonfat protein). Research
E = baking energy rate, Btu/h or kW,
bake rate
conducted by Pacific Gas and Electric Company determined that the
E = energy consumed during the pie baking test, Btu
weighted average of the specific heat for frozen apple pies specified as in
section 7.3 was approximately 0.63 Btu/lb °F. or kWh, and
t = pie baking test period, min.
T = final average internal temperature of the baked pies,
f
For gas appliances, report separately a gas baking energy
°F,
rate and an electric baking energy rate.
T = initial average internal temperature of the frozen
i
11.11.3 Calculate and report the energy consumption per
pies, °F,
pound of food cooked for the baking tests based on:
E = latent heat (of fusion) added to the food, which
thaw
causes the moisture (in the form of ice) contained in
E
appliance
E 5 (8)
the food to melt when the temperature of the food per pound
W
reaches 32°F (the additional heat required to melt the
where:
ice is not reflected by a change in the temperature of
E = energy per pound, Btu/lb or kWh/lb,
the food), Btu,
per pound
E = energy consumed during the baking test, Btu or
= W × H appliance
iw f
kWh, and
where:
W = initial weight of the frozen pies, lb.
W = initial weight of water in the pies, lb,
iw
11.11.4 Calculate and report the production capacity (lb/h)
× W
= M
i i
based on:
where:
W × 60
PC 5 (9)
M = the average initial moisture of the pies (Annex A2),
i t
%,
where:
W = the initial weight of the frozen pies, lb,
i
H = heat of fusion, Btu/lb, PC = production capacity of the rack oven, lb/h,
f
F2093 − 18 (2023)
determined. The repeatability of browning uniformity cannot
W = total weight of frozen pies (excluding pan weights)
be determined because of the descriptive nature of the test
cooked during heavy-load baking test, lb, and
result.
t = total bake time for the heavy-load test, min.
12.1.2 Reproducibility (multiple laboratories)
11.11.5 Report the average bake time for the full-load
12.1.2.1 The inter-laboratory precision of the procedure in
baking tests.
this test method for measuring each reported parameter, with
the exception of browning uniformity, is being determined. The
12. Precision and Bias
reproducibility of browning uniformity cannot be determined
12.1 Precision: because of the descriptive nature of the test result.
12.1.1 Repeatability (within laboratory, same operator and
12.2 Bias:
equipment)
12.2.1 No statement can be made concerning the bias of the
12.1.1.1 For the baking energy efficiency and production
procedures in this test method because there are no accepted
capacity results, the percent uncertainty in each result has been
reference values for the parameters reported.
specified to be no greater than 6 10 % based on at least three
13. Keywords
test runs.
12.1.1.2 The repeatability of each remaining reported 13.1 bake time; energy efficiency; performance; production
parameter, with the exception of browning uniformity, is being capacity; rack oven; test method
ANNEXES
(Mandatory Information)
A1. PROCEDURE FOR DETERMINING THE UNCERTAINTY IN REPORTED TEST RESULTS
NOTE A1.1—This procedure is based on the ASHRAE method for TABLE A1.1 Uncertainty Factors
determining the confidence interval for the average of several test results
Test Results, n Uncertainty Factor, Cn
(ASHRAE Guideline 2-1986 (RA90)). It should only be applied to test
3 2.48
results that have been obtained within the tolerances prescribed in this
4 1.59
method (for example, thermocouples calibrated, appliance operating
5 1.24
within 5 % of rated input during the test run).
6 1.05
7 0.92
A1.1 For the baking energy efficiency and production ca-
8 0.84
9 0.77
pacity results, the uncertainty in the averages of at least three
10 0.72
test runs is reported. For each loading scenario, the uncertainty
of the baking energy efficiency and production capacity must
be no greater than 610 % before any of the parameters for that
A1.4.1 Step 1—Calculate the average and the standard
loading scenario can be reported.
deviation for the test result (cooking-energy efficiency or
production capacity) using the results of the first three test runs,
A1.2 The uncertainty in a reported result is a measure of its
as follows:
precision. If, for example, the production capacity for the
A1.4.1.1 The formula for the average (three test runs) is as
appliance is 100 lb/h, the uncertainty must not be greater than
follows:
610 lb/h. Thus, the true production capacity is between 90 and
110 lb/h. This interval is determined at the 95 % confidence
Xa 5 × ~X 1X 1X ! (A1.1)
S D
3 1 2 3
level, which means that there is only a 1 in 20 chance that the
true production capacity could be outside of this interval.
where:
A1.3 Calculating the uncertainty not only guarantees the
Xa = average of results for three test runs, and
maximum uncertainty in the reported results, but is also used to X , X , X = results for each test run.
1 2 3
determine how many test runs are needed to satisfy this
A1.4.1.2 The formula for the sample standard deviation
requirement. The uncertainty is calculated from the standard
(three test runs) is as follows:
deviation of three or more test results and a factor from Table
S 5 1/=2 × = A 2 B (A1.2)
~ ! ~ !
3 3 3
A1.1, which lists the number of test results used to calculate the
average. The percent uncertainty is the ratio of the uncertainty
where:
to the average expressed as a percent.
S = standard deviation of results for three test runs,
2 2 2
A = (X ) + (X ) + (X ) , and
3 1 2 3
A1.4 Procedure:
B = ( ⁄3) × (X + X + X )
3 1 2 3
NOTE A1.2—Section A1.5 shows how to apply this procedure.
F2093 − 18 (2023)
NOTE A1.3—The formulas may be used to calculate the average and
S 5 ~1/=3! ×= A 2 B (A1.6)
~ !
4 4 4
sample standard deviation. However, a calculator with statistical function
is recommended, in which case be sure to use the sample standard
where:
deviation function. The population standard deviation function will result
S = standard deviation of results for four test runs,
in an error in the uncertainty.
2 2 2 2
A = (X ) + (X ) + (X ) + (X ) , and
4 1 2 3 4
NOTE A1.4—The “A” quantity is the sum of the squares of each test
B = ( ⁄4) × (X + X + X + X )
result, and the “B” quantity is the square of the sum of all test results
4 1 2 3 4
multiplied by a constant ( ⁄3 in this case).
A1.4.7 Step 7—Calculate the absolute uncertainty in the
A1.4.2 Step 2—Calculate the absolute uncertainty in the
average for each parameter listed in Step 1. Multiply the
average for each parameter listed in Step 1. Multiply the
standard deviation calculated in Step 6 by the Uncertainty
standard deviation calculated in Step 1 by the Uncertainty
Factor for four test results from Table A1.1.
Factor corresponding to three test results from Table A1.1.
A1.4.7.1 The formula for the absolute uncertainty (four test
A1.4.2.1 The formula for the absolute uncertainty (3 test
runs) is as follows:
runs) is as follows:
U 5 C × S , (A1.7)
4 4 4
U 5 C × S , (A1.3)
3 3 3
U 5 1.59 × S
4 4
U 5 2.48 × S
3 3
where:
where:
U = absolute uncertainty in average for four test runs, and
U = absolute uncertainty in average for three test runs, and
3 C = the uncertainty factor for four test runs (Table A1.1).
C = uncertainty factor for three test runs (Table A1.1).
A1.4.8 Step 8—Calculate the percent uncertainty in the
A1.4.3 Step 3—Calculate the percent uncertainty in each
parameter averages using the averages from Step 6 and the
parameter average using the averages from Step 1 and the
absolute uncertainties from Step 7.
absolute uncertainties from Step 2.
A1.4.8.1 The formula for the percent uncertainty (four test
A1.4.3.1 The formula for the percent uncertainty (3 test
runs) is as follows:
runs) is as follows:
%U 5 ~U /Xa ! × 100 % (A1.8)
4 4 4
%U 5 U /Xa × 100 % (A1.4)
~ !
3 3 3
where:
where:
%U = percent uncertainty in average for four test runs,
%U = percent uncertainty in average for three test runs,
U = absolute uncertainty in average for four test runs,
U = absolute uncertainty in average for three test runs,
and
and
Xa = average of four test runs.
Xa = average of three test runs.
A1.4.9 Step 9—If the percent uncertainty, %U , is not
A1.4.4 Step 4—If the percent uncertainty, %U , is not
greater than 6 10 % for the baking energy efficiency and
greater than 610 % for the cooking-energy efficiency and
production capacity, report the average for these parameters
p
...