ASTM F1920-20

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: F1920 − 20 An American National Standard
Standard Test Method for
Performance of Rack Conveyor Commercial Dishwashing
Machines
This standard is issued under the fixed designation F1920; 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 1.3.1.5 Wash tank temperature calibration (10.3).
1.3.1.6 Wash tank pump and conveyor motor calibration
1.1 This test method evaluates the energy and water con-
(10.4).
sumption of rack conveyor, commercial dishwashing
1.3.2 Energy Usage and Cycle Rate Performance Tests:
machines, hereafter referred to as dishwashers. Dishwashers
1.3.2.1 Washing energy performance test (10.8).
may have remote or self-contained booster heater. This proce-
1.3.2.2 Tank heater idle energy rate (10.9).
dure does not address cleaning or sanitizing performance.
1.3.2.3 Booster idle energy rate, if provided (10.10).
1.2 This test method is applicable to both hot water sanitiz-
1.4 The values stated in inch-pound units are to be regarded
ing and chemical sanitizing rack conveyor machines, which
as standard. The values given in parentheses are mathematical
include both single tank and multiple tank machines. Rackless
conversions to SI units that are provided for information only
conveyors (i.e. flight type machines) are included. Dishwasher
and are not considered standard.
tank heaters are evaluated separately from the booster heater.
Machinesdesignedtobeinterchangeableinthefieldfromhigh
1.5 This standard does not purport to address all of the
temp and low temp (i.e. Dual Sanitizing Machines) and vice
safety concerns, if any, associated with its use. It is the
versa, shall be tested at both settings. Machines should be set
responsibility of the user of this standard to establish appro-
for factory settings. If a dishwasher includes a prewash tank
priate safety, health, and environmental practices and deter-
heaterasanoption,energyshouldbesubmeteredseparatelyfor
mine the applicability of regulatory limitations prior to use.
the prewash tank heater. This test method may be used for
1.6 This international standard was developed in accor-
dishwashers with steam coil tank or booster heat, but not
dance with internationally recognized principles on standard-
dishwashers with steam injection tank or booster heat. When
ization established in the Decision on Principles for the
thetestmethodspecifiestousethedataplateormanufacturer’s
Development of International Standards, Guides and Recom-
recommendations,instructions,specifications,orrequirements,
mendations issued by the World Trade Organization Technical
the information source shall be used in the following order of
Barriers to Trade (TBT) Committee.
preference and documented in the test report: data plate, user
manual, communication with manufacturer.
2. Referenced Documents
1.3 The following procedures are included in this test 2
2.1 ASTM Standards:
method:
D3588Practice for Calculating Heat Value, Compressibility
1.3.1 Procedures to Confirm Dishwasher is Operating
Factor, and Relative Density of Gaseous Fuels
Properly Prior to Performance Testing:
F858Specification for Hot Water Sanitizing Commercial
1.3.1.1 Maximum energy input rate of the tank heaters
Dishwashing Machines, Single Tank, Conveyor Rack
(10.5).
Type
1.3.1.2 Maximum energy input rate of the booster heater, if
F861Specification for Commercial Dishwashing Racks
applicable (10.6).
2.2 NSF Standards:
1.3.1.3 Final sanitizing rinse water consumption calibration
NSF/ANSI 3Commercial Warewashing Equipment
(10.7).
NSF/ANSI 170Glossary of Foodservice Terms
1.3.1.4 Boostertemperaturecalibration,ifapplicable(10.2).
1 2
This test method is under the jurisdiction of ASTM Committee F26 on Food For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Service Equipment and is the direct responsibility of Subcommittee F26.06 on contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Productivity and Energy Protocol. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved Sept. 1, 2020. Published October 2020. Originally the ASTM website.
approved in 1998. Last previous edition approved in 2015 as F1920–15. DOI: Available from NSF International, P.O. Box 130140, 789 N. Dixboro Rd.,Ann
10.1520/F1920-20. Arbor, MI 48113-0140, http://www.nsf.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F1920 − 20
2.3 ASHRAE Standard: 3.1.14 energy saver mode, n—operational setting that is
ASHRAE Guideline 2–1986 (RA90)Engineering Analysis designedtoreduceenergyduringidlemodethroughtemporary
of Experimental Data shut-down of certain machine components (pumps or belt
motors) or reduction of certain temperature set points.
3. Terminology
3.1.15 factory settings, n—a setting that has been pro-
3.1 Definitions of Terms Specific to This Standard:
grammed or adjusted at the factory and is representative of the
3.1.1 ambient temperature, n—defined in NSF/ANSI 170-
waythatmodelissetupinitially.Thesesettingsarethedefault
2014; Section 3.3.
settingsforthemachineandmayormaynotbeuseradjustable.
3.1.2 auxiliary rinse, n—defined in NSF/ANSI 170-2014;
3.1.16 flight type conveyor, n—a conveyor machine where
Section 3.5.
the dishes are loaded directly on the conveyor rather than
3.1.3 average tank temperature, n—temperatureofthewash transported within a rack. This machine is also referred to as a
tank measured within ⁄2 in. of the factory installed thermostat rackless conveyor.
bulb.The temperature is measured and averaged during the 25
3.1.17 flow pressure, n—defined in NSF/ANSI 170-2014;
rack (50 racks for flight type) loaded ambient temperature (per
Section 3.76.
9.1) washing test. The temperature is averaged over the entire
3.1.18 fresh water, n—defined in NSF/ANSI 170-2014;
period starting with the entry of the first loaded dish rack and
Section 3.85.
endingwhenbothwashtankandboosterelementshavecycled
3.1.19 heat recovery dishwasher, n—warewashing equip-
off after the last rack is washed. Stabilization loads should not
ment with heat recovery systems; a heat exchanger that
be included in the average wash tank temperature.
recovers energy from other sources for the purpose of heating
3.1.4 batch, n—a group of five dishloads as described in
potable water. This includes but is not limited to drain water
3.1.10.
heat exchangers, wash compartment heat exchangers, exhaust
3.1.4.1 Discussion—The dishracks are grouped into batches
heat exchangers, and supplemental heat pumps.
to better simulate typical in-kitchen operation and facilitate
3.1.20 hot water sanitizing (high temp) machine, n—a
consistent application of the washing energy use test.
machine that applies hot water to the surfaces of dishes to
3.1.5 booster heater, n—water heater for taking supply hot
achieve sanitization.
water (typically 140°F (60°C)) up to 180°F+ (82°C+) for
3.1.21 hot water sanitizing rinse, n—defined in NSF/ANSI
sanitizing rinse; the booster heater may be separate from
170-2010; Section 3.171.
dishwasherorintegral.BoosterHeaterisdefinedinNSF/ANSI
170-2014; Section 3.224.1. 3.1.22 idle mode, n—for all dishwasher types, the dish-
washer is in idle mode when it is not actively running but is
3.1.6 chemicalsanitizing(lowtemp)machine,n—amachine
still powered on and ready to wash dishes while maintaining
that applies a chemical sanitizing solution to the surfaces of
the tank or tanks at the required temperature.
dishes to achieve sanitization.
3.1.23 line pressure, n—defined in NSF/ANSI 170-2014;
3.1.7 chemical sanitizing rinse, n—defined in NSF/ANSI
Section 3.115.
170-2010; Section 3.170.
3.1.24 multiple tank conveyor, n—a conveyor type machine
3.1.8 conveyor machine, n—a dishwashing machine that
thatincludesoneormoretanksforwashwaterandoneormore
employs a conveyor or similar mechanism to carry dishes
tanks for pumped rinse water, followed by a sanitizing rinse.
through a series of wash and rinse sprays within the machine.
Thistypeofmachinemayincludeapre-washingsectionbefore
3.1.9 cycle rate, n—maximum production rate of a dish-
thewashingsectionandanauxiliaryrinsesection,forpurposes
washer when washing dishloads in accordance with the Cycle
of reusing the sanitizing rinse water, between the power rinse
Rate Performance test.
and sanitizing rinse section. Multiple tank conveyor dishwash-
3.1.10 dishload, n—peg-type, polypropylene dishrack of a
ers can be either chemical or hot water sanitizing, with an
specified weight, loaded with ten 9-in. plates of a specified
internal or external booster heater for the latter.
weight,usedtoputathermalloadonthedishwasherduringthe
3.1.25 non-recirculating pumped sanitizing rinse,
washing energy test.
n—defined in NSF/ANSI 170-2014; Section 3.131.
3.1.11 dishwasher, n—for this test method, a machine that
3.1.26 post-sanitizing rinse, n—defined in NSF/ANSI 170-
uniformly washes, rinses, and sanitizes eating and drinking
2014; Section 3.174.
utensils and cookware.
3.1.27 prewashingunit,n—definedinNSF/ANSI170-2014;
3.1.12 dual sanitizing machine, n—a machine designed to
Section 3.150.
operateaseitheraChemicalSanitizingorHotWaterSanitizing
3.1.28 pumped rinse, n—defined in NSF/ANSI 170-2014;
machine.
Section 3.154.
3.1.13 empty dish rack, n—dish rack without any dishware
3.1.29 rack, n—defined in NSF/ANSI 170-2014; Section
placed in the dish rack.
3.157.
3.1.30 rated temperature, n—dishwasher’s rated data plate
Available from American Society of Heating, Refrigerating, and Air-
minimum operating tank temperature as determined by NSF/
Conditioning Engineers, Inc. (ASHRAE), 1791 Tullie Circle, NE, Atlanta, GA
30329, http://www.ashrae.org. ANSI 3.
F1920 − 20
3.1.31 recirculating sanitizing rinse, n—defined in NSF/ 4.3 Water consumption is adjusted in accordance with
ANSI 170-2014; Section 3.162. manufacturer’s rated water consumption per NSF/ANSI 3.
Report the measured consumption and confirm that it is within
3.1.32 recovery time, n—time from the end of washing a
5 % of the listing on the data plate. If the difference is greater
dishload to until the wash tank heaters have cycled off.
than 5 %, terminate testing and contact the manufacturer. The
3.1.33 sanitization, n—defined in NSF/ANSI 170-2014;
manufacturer may make appropriate changes or adjustments to
Section 3.178.
the dishwasher or provide another unit for testing.
3.1.34 sanitizing rinse, n—defined in NSF/ANSI 170-2010;
4.4 Thetankheaterenergyrateisdeterminedatidle,thatis,
Section 3.173.
whenthetanktemperatureisbeingmaintained,butnowashing
3.1.35 sanitizing solution, n—defined in NSF/ANSI 170-
is taking place.
2014; Section 3.179.
4.5 Booster heater idle energy rate is determined.
3.1.36 single tank conveyor, n—a conveyor machine that
4.6 Dishwasherandboosterenergyconsumptionperrackof
includes a tank for wash water followed by a sanitizing rinse
dishes is determined during a heavy-use scenario by washing
(pumped or fresh water). This type of machine does not have
racks loaded with a specified quantity of dishes
a pumped rinse tank. This type of machine may include a
4.7 Water consumption is monitored during testing to deter-
prewashing section ahead of the washing section and an
mine the rate of water usage.
auxiliary rinse section, for purposes of reusing the sanitizing
rinse water, between the wash and sanitizing rinse sections.
5. Significance and Use
Singletankconveyordishwasherscanbeeitherchemicalorhot
water sanitizing, with an internal or external booster heater for 5.1 The maximum energy input rate test is used to confirm
the latter.
that the dishwasher is operating at the manufacturer’s rated
inputpriortofurthertesting.Thistestmethodalsowillindicate
3.1.37 tank heater idle energy rate, n—rate of energy
any problems with the electric power supply, gas service
consumed by the dishwasher while “holding” or maintaining
pressure, or steam supply flow or pressure.
the wash tank water at the thermostat(s) set point during the
time period specified.
5.2 Tank and booster temperatures, as well as water
consumption, are adjusted to NSF specifications to insure that
3.1.38 uncertainty, n—measure of systematic and precision
the test is applied to a properly functioning dishwasher.
errors in specified instrumentation or measure of repeatability
of a reported test result.
5.3 Because much of a dishwasher’s operating period is
spent in the idle condition, tank heater and booster idle energy
3.1.39 user adjustable, n—settingthatcanbechangedbyan
consumption rate(s) are important parts of predicting dish-
end user without having access to features reserved for
washer’s energy consumption.
appliance technicians. A password usually separates user ad-
justable and technician adjustable features in digital appliance
5.4 Thewashingenergyperformancetestdeterminesenergy
controls.Nonuseradjustablemanualcontrolsrequireapanelto
usage per rack.This is useful both as a measure for comparing
be removed to access that feature.
the energy performance of one dishwasher to another and as a
predictor of the dishwasher’s energy consumption.
3.1.40 washing, n—defined in NSF/ANSI 170-2014; Sec-
tion 3.222.
5.5 Water-consumption characterization is useful for esti-
mating water and sewage costs associated with dishwashing
3.1.41 water heater, n—defined in NSF International/
American National Standards Institute (NSF/ANSI) 170-2014: machine operation.
Glossary of Food Equipment Terminology; Section 3.224.
6. Apparatus
NOTE 2—For all instruments, the specifications may be better than
4. Summary of Test Method
specified. Values provided are intended to be the minimum or maximum
(depending on which is the worst case for the parameter) allowable.
4.1 The booster temperature (for high temperature ma-
chines) is calibrated and verified.
6.1 1 or 2 watt-hour (Wh) Meters, for measuring the
electricalenergyconsumptionofthetankheaters,pumpmotor,
4.2 The maximum energy input rate of the tank heater and
and booster heater, if applicable, shall have a resolution of at
theboosterheater,ifapplicable,ismeasuredtoconfirmthatthe
least10Whandamaximumaccuracynogreaterthan1.5%of
dishwasherisoperatingatthemanufacturer’sratedinput.Ifthe
themeasuredvalueforanydemandgreaterthan100watts(W).
measured input rate is not within 5% of the rated input or the
For any demand less than 100 W, the meter shall have a
ratingprintedontheheatingelement,allfurthertestingceases.
resolution of at least 10 Wh and a maximum accuracy no
NOTE 1—It is the intent of the testing procedure herein to evaluate the
greater than 10% of the measured value.
performance of a dishwasher at its rated gas pressure or electric voltage.
If an electrical unit is rated dual voltage, that is, designed to operate at 6.2 1 or 2 Gas Meters, for measuring the gas consumption
either 208 or 240 volts (V) with no change in component, the voltage
of tank heater, or booster heater, if applicable, or both, shall
3 3
selected by the manufacturer or the tester, or both, shall be reported. If a
have a resolution of at least 0.1 cubic feet (ft )(0.003 m ), a
dishwasher is designed to operate at two voltages without a change in the
maximum accuracy no greater than 1% of the measured value
resistance of the heating elements, the performance of the unit, for
3 3
for any demand greater than 2.2 ft /h (0.06 m /h), and shall be
example, cycle rate, may differ at the two voltages. Therefore the tests
may be performed at both voltages and the results reported accordingly. capable of measuring flows between at least 0 and 250 ft /h
F1920 − 20
(7.08 m /h). Pilot light gas consumption should be measured 6.11 Stop Watch, with a resolution of at least 0.1 second (s)
for at least an 8 h period. and an accuracy of 6 2% of the time period being measured.
6.3 1 or 2 Steam Flow Meters, for measuring the flow of 6.12 Analytical Balance Scale, or equivalent, for measuring
steam to tank heaters and or booster heater, if applicable, shall weight of dishes and dish racks used in the dishload energy
3 3
havearesolutionof0.01ft (0.0003m ),amaximumaccuracy test. Capable of weighing a minimum of 20 lb (9 kg). It shall
of 1% of the measured value, and shall be capable of have a resolution of at least 0.01 lb (5 g) and an accuracy of
3 3
measuringflowsbetweenatleast0and50ft /h(1.42m /h)and 0.01 lb (5 g) or better.
recording data at least as frequently as every second.
6.13 Temperature Sensor,witharangefrom50to250°F(10
6.4 Pressure Gauge, for measuring pressure of steam to to 121°C), with a resolution of 0.2°F (0.1°C), an accuracy of
steam coils, shall have a resolution of 0.5 pounds per square 1%, and a response time of less than two seconds for
inch gage (psig) (3.4 kPa), a maximum accuracy of 1% of the measuring tank temperature, booster and dishwasher inlet
measured value, and shall be capable of measuring pressures temperatures. For dishwashers with steam coil tank or booster
between at least 0 and 100 psig (689.5 kPa). heat, the thermocouple probes shall be used for measuring the
condensatewateroutlettemperature.CalibratedK-type24-GA
6.5 Pressure Gauge, for water consumption test, shall be
thermocouple wire with stainless steel sheath and ceramic
capable of measuring at least 0 to 30 psig (207 kPa) with a
insulation is the recommended choice for measuring the
resolution of at least 1 psig (6.9 kPa) and a maximum
booster and dishwater inlet temperatures. The thermocouple
uncertainty of 3% of the measured value.
probe can be fed through a compression fitting so as to
6.6 Canopy Exhaust Hood or Vent Cowl Exhaust Ducts,
submerge exposed junction in booster and dishwasher inlets.
measured in agreement with manufacturers requirements.Vent
6.14 Dishracks, minimum of 30 (60 for flight type
cowl exhaust ducts shall operate in accordance with the
3 3
machines), 19 ⁄4 by 19 ⁄4 by 4 in. (50.2 by 50.2 by 10.2 cm),
manufacturer’s recommendation, if applicable, or at a nominal
peg-type, polypropylene commercial or acceptable equivalent
200cubicfeetperminute(cfm)(94.4L/s)ontheentranceside
(for example, Carlisle RP14, Cambro PR314L40151). Each
of dishwasher and 400 cfm (188.8 L/s) on the exit side if the
shall weigh 4.4 6 0.2 lb (2 6 0.09 kg), and be used in the
manufacturer does not provide recommendations. Canopy
washing energy performance test (see 10.8).
exhaust hood shall extend at least 1 ft beyond the dishwashing
machinefootprintoperatingatthedishwashingmachinemanu- 6.15 Plates,minimumof300(600forflighttypemachines),
facturer’s specified ventilation rate. Report the ventilation rate 9-in. (23 cm), ceramic glazed plates, weighing 1.3 6 0.05 lb
and ventilation exhaust type. (0.6 6 0.02 kg) each.
6.7 Pressure Gauge, for monitoring natural gas pressure,
NOTE 3—Inter-American® mdl #132 are within the specified weight
range and are inexpensive.
shallhavearangeof0to10incheswater(in.H O)(zeroto2.5
kPa), a resolution of 0.1 in. H O (125 Pa), and a maximum
2 6.16 SurfaceTemperatureThermocoupleProbe,formeasur-
accuracy of 3% of the measured value.
ing dish plates and dishracks temperatures. Resolution and
accuracy shall be the same as in 6.13.
6.8 Temperature Sensor, for measuring natural gas and
ambient air temperatures in the range of 50 to 100°F (10 to
7. Sampling
40°C), with a resolution of at least 0.5 degrees Fahrenheit (°F)
(0.3°C) and a maximum accuracy of 1% (0.5°C). For dish-
7.1 Dishwasher—A representative production model shall
washers with steam coil tank or booster heat, the temperature
be selected for performance testing.
sensorformeasuringsteamtemperaturesintherangeof200to
300°F (93 to 149°C) shall have a resolution of at least 0.5°F 8. Materials
and a maximum accuracy of 1%.
8.1 As specified in 6.14, the dishracks must be made of
6.9 Barometer, for measuring absolute atmospheric polypropylene. This material is required because the test
pressure, to be used for adjustment of measured natural gas
method assumes a specific heat of 0.39 Btu/(lb × °F). One
volume to standard conditions if the gas flow meter does not verificationthatarackispolypropyleneisifithastherecycling
correct for pressure, or for calculating absolute pressure from
symbol No. 5 on it with the letters “PP” below the symbol.
gage pressure if the pressure gauge does not correct for
atmospheric pressure for steam coil tank or booster heat, shall 9. Preparation of Apparatus
have a resolution of 0.2 inches mercury (in. Hg) (670 Pa), and
9.1 Install the dishwasher in accordance with the dish-
an accuracy of 0.2 in. Hg (670 Pa).
washer manufacturer’s instructions connected to vent cowl
6.10 Flow Meter, for measuring water consumption of the exhaust ducts or a canopy hood extending at least 1 ft (0.3 m)
dishwasher. The calibrated flow meters shall have a resolution beyond the dishwashing machine footprint. Vent cowl exhaust
ofatleast0.01gal(40mL),amaximumaccuracyof1%offull ducts should operate at a nominal 200 cfm (94.4 L/s) on the
scaleandshallbecapableofmeasuringflowratesaslowas0.2 entrance side of dishwasher and 400 cfm (188.8 L/s) on the
gpm (13 mL/s).The maximum flowrate of the machine should discharge side or in accordance with manufacturer’s
not exceed 90% of the meter’s upper measurement range. If recommendations, if applicable. Record the ventilation rate
using a data acquisition system, water meters should have the used for the testing. The associated heating or cooling system
capability of outputting a minimum of 100 pulses per gallon. shall be capable of maintaining an ambient temperature of 75
F1920 − 20
6 5°F (23.9 6 3°C) within the testing environment when the the appliance’s pressure regulator to within 65% of the
exhaust ventilation system is working and the appliance is operating manifold pressure specified by the manufacturer.
being operated. Make adjustments to the dishwasher following the manufac-
turer’s recommendations for optimizing combustion, as appli-
9.2 Install the booster heater, if it is not integral to the
cable.
dishwasher, in accordance with the manufacturer’s recommen-
dations. The pipe from the booster outlet to the dishwasher
9.8 Install the flow meter (6.10), such that total water flow
inlet shall be minimized and shall be wrapped with ⁄2-in.
to the booster and dishwasher is measured. Install a separate
insulation along its entire length.
water meter for each water machine connection including tank
top-off and auxiliary rinse.
9.3 Connect the booster to a supply of water, which is
withintherangeofthemanufacturerspecifiedinputrate,notto
9.9 Install a temperature sensor(s) (6.13) in the tank within
exceed 140 62°F (60 6 1.1°C). For heat recovery machines, 1
⁄2 in. (1.3 cm) the factory installed thermostat bulb.
connect the cold water supply to 70 6 3°F (21.1 6 1.7°C)
9.10 Install a temperature sensor (6.13) at the inlet to the
water. For testing purposes, the dishwasher may be connected
dishwasher’s sanitizing rinse water manifold and in the inlet
to a source of water that is at the manufacturer specified
and outlet the booster heater. Install temperature sensors on
sanitizing rinse temperatures in lieu of an external booster
each additional water inlet to the machine. The sensors should
heater.
be installed with the probe immersed in the water.
NOTE 4—A heat recovery dishwasher may have a hot and cold water
NOTE 5—Install the thermocouple probes described in 6.13 into
inlet.Typicallyforrinsingonlythecoldwaterisused,whileforfillingthe
sanitizing rinse water manifold for the dishwasher and into the supply
hot water is used, sometimes in combination with the cold water.
water inlet at the booster. The thermocouple probe must be installed so
9.4 Connectthedishwashertoacalibratedenergytestmeter
that the thermocouple probe is immersed in the incoming water. A
so that all energy (including tank heater(s), motors and
compression fitting should be first installed into the plumbing for both
inlets.Ajunction fitting may need to be installed in the plumbing line that
controls) is monitored. Connect the booster to a separate
would be compatible with the compression fitting.
calibratedenergytestmeter.Forsteamcoilorgasdishwashers,
electricenergyconsumptionshallbesimultaneouslymonitored 9.11 Install dishwashing machine’s strip (end) curtains in
with steam or gas energy consumption. The dishwasher and
accordance to manufacturer’s recommendations.
booster shall not be monitored as one energy load. Separate
9.12 Preparation of Dishloads:
monitoringwillbroadentheusefulnessofthedataandenhance
9.12.1 This section describes preparation of the 30 (60 for
the accuracy of the results. Internal booster heaters shall be
flight type) dishloads (5 stabilization dishloads and 25 test
monitored separately and the booster idle energy shall be
dishloads, 10 and 50 for flight type) and two empty racks to be
reported separately from the total idle energy.
used in the washing energy performance test.
9.5 For gas installations, install a pressure regulator (down-
9.12.2 An important feature of the washing energy perfor-
stream from the meter) to maintain a constant (manifold)
mance test is that every dishwasher be subjected to the same
pressure of gas supplied to the dishwasher and booster heater,
thermal load. To accomplish this feature, the tester must
ifapplicable,foralltests.Installinstrumentationtorecordboth
control some of the factors that affect the thermal load. These
the pressure and temperature of the gas supplied to the
factors are as follows.
dishwasherandthebarometricpressureduringeachtestsothat
9.12.2.1 The total weight of the dishes,
the measured gas flow can be corrected to standard conditions
9.12.2.2 The weight of the (empty) racks, and
if the gas flow meter does not already correct for pressure and
9.12.2.3 The initial temperature of the dishes and racks.
temperature. For steam coil tank or booster heat installations,
9.12.3 Theweightofthedryracksisspecifiedin6.14as4.4
install instruments to provide dry superheated steam to the
6 0.2 lb (2 6 0.09 kg) per rack. If they weigh greater than 4.6
dishwasher.Adjustthesteamsupplypressuretowithin 62.5%
lb, trim away material until they weigh 4.4 6 0.2 lb (2 6 0.09
of the operating pressure specified by the manufacturer. Install
kg).Toseewhatpartsoftherackarenotneededforthetestand
instrumentation to record the pressure, temperature, and volu-
maythereforebetrimmed,itmaybedesirabletoloadtheracks
metric flow rate of the steam supplied to the dishwasher tank
astheywillbeusedduringthetest.Theloadingisexplainedin
heater (and booster heater separately, if applicable), the pres-
9.12.4 and 9.12.5.
sure and temperature of the condensate exiting the dishwasher
9.12.4 Prepare 30 (60 for flight type) dishloads as described
tank heater (and booster heater separately, if applicable), and
in this and the following step (9.12.5). Each dishload must
the barometric pressure during each test so that the measured
have13.0 60.5lb(5.9 60.2kg)ofplates.Ideally,thissimply
gage pressures can be corrected to absolute pressure.
requires ten 9-in. plates. If total weight of the ten 9-in. plates
9.6 Forelectrictankheatersandboosters,confirm,whilethe
does not fall within the range, then change individual plates to
elements are energized, that the supply voltage is within 65%
achieve the specified weight range.
of the operating voltage specified by the manufacturer. If it is
9.12.5 Theplatesshouldbespacedevenlyontheracks.The
not, a voltage regulator may be required during the tests.
plate spacing shall be the same on all racks.
Recordthetestvoltageforeachtest.Ifthemachinehasseveral
9.12.6 The bulk temperature of the dishloads before wash-
electrical connections, record the voltages separately.
ing must be 75 6 2°F (24 6 1°C). This can be accomplished
9.7 For gas tank heaters and boosters, during maximum bystoringthedishloadsinaroomwithanambienttemperature
energy input, adjust the gas supply pressure downstream from of 75 6 2°F (24 6 1°C).Avoid any circumstances that would
F1920 − 20
result in some dishes being at different temperatures from 10.2.1 For external booster heaters, while monitoring the
others, such as being stored in the air path of an HVAC supply water inlet of the booster heater or water source and dish-
register. Determine the bulk temperature using a surface washer (rinse manifold) temperature, initiate a dishwasher
temperature probe (6.16), measuring the temperature of three cycle. Adjust the booster heater or water source to the
plates (one front, one center, and one rear) of each dishrack. manufacturer’s recommended sanitizing rinse temperature 6
Average these temperatures to determine the bulk temperature. 2°F (6 1.1°C), if user adjustable. If the manufacturer does not
have a recommended external booster heater setting, then set
9.13 Conveyor and wash pump motor operation may be
theboosterheaterthermostatsuchthattheaveragetemperature
adjustable. If adjustable calibrate as described in 10.4.
ofwateratthedishwashermanifold(measuredonlyduringthe
rinse)isbetween180and195°F(82and91°C).Ifthemachine
10. Procedure
is supplied with an internal booster heater, retain the factory
10.1 General:
setting of the thermostat.
10.1.1 Obtainandrecordthefollowingforeachrunofevery
10.3 Run two empty dishracks through the machine. Con-
test (gas, electric, and steam coil).
firm that the stabilized flowing sanitizing rinse temperature is
10.1.1.1 Voltage of each electrical connection while ele-
abovethemanufacturer’sratedsanitizingrinsetemperature(or
ments are energized.
above 180°F (82°C) if the manufacturer does not provide a
10.1.2 For dishwashers with a gas powered tank heater or
rated sanitizing rinse temperature). If the stabilized flowing
booster the following shall be obtained and recorded for each
sanitizing rinse temperature is below the manufacturer’s data
run of every test if the gas meter does not already correct the
plateratedsanitizingrinsetemperature(orbelow180°F(82°C)
gas volume based on temperature and pressure.
if the manufacturer does not provide a rated sanitizing rinse
10.1.2.1 Higher heating value.
temperature), adjust the thermostat per the manufacturer’s
10.1.2.2 Standard gas conditions of calculation in 11.3.
instructions if it is user adjustable not to exceed the manufac-
10.1.2.3 Measure gas temperature.
turer’s rated sanitizing temperature +15°F (8.3°C). Submerged
10.1.2.4 Measured line gas pressure (before pressure regu-
thermocouple probes may take up to 10 s to stabilize during
lator).
rinse, so the first 10 s of rinse temperature data shall be
10.1.2.5 Barometric pressure.
discarded.
NOTE 6—For a gas appliance, the quality of heat (energy) generated by
10.4 Wash Tank Pump and Conveyor Motor Calibration:
thecompliancecombustionofthefuelisknownastheheatingvalue,heat
of combustion, or calorific value of that fuel. For natural gas, this heating 10.4.1 Dishwashing machines may be equipped with auto-
value varies according to the constituents of the gas. It is measured in
matic shut-down that stop the pump(s) and conveyor motors
Btu/ft . The heating value should be obtained during testing and used in
when no racks are being washed. For wash tank pump and
the determination of the energy input to the appliance.
conveyor motors that have automatic or adjustable operation
NOTE7—Thepreferredmethodfordeterminingtheheatingvalueofgas
time, if user adjustable, set the controls so motors automati-
supplied to the dishwasher under testing is by using a calorimeter or gas
chromatograph in according with accepted laboratory procedures. It is cally shut off after the manufacturer’s recommended (or
recommended that all testing be performed with gas with a heating value
factorydefaultsetting)operatingperiodduringwashingenergy
3 3
between 1 000 and 1075 Btu/ft (37300 to 40100 kJ/m ). The use of
performance testing.
“bottle”naturalgaswithacertifiedheatingvaluewithinthespecified1000
3 3
10.4.2 Somedishwashermachinesareequippedwithafinal
to 1075 Btu/ft (37300 to 40100 kJ⁄m ) range is an acceptable alterna-
tive.
rinse catch pan (final rinse water saver) to capture the water
from the rinse cycle. Set the catch pan drain to manufacturer’s
10.1.3 For gas dishwashers, energy calculations shall be in
recommended setting. Report final rinse catch pan drain
accordance with 11.3.
setting.
10.1.4 For dishwashers that use steam coils for tank or
10.4.3 Ifconveyorspeedisuseradjustable,settomaximum
booster heat, the steam temperature, pressure, and instanta-
conveyor speed as specified in NSF/ANSI 3 and report
neous or average volumetric flow rate at dishwasher inlet shall
conveyor speed. If not user adjustable, retain factory setting.
be recorded at intervals no greater than one second of every
test. Cumulative flow rate and average temperatures and
10.5 Tank Heater Maximum Energy Input Rate (that is,
pressurescanbemeasuredandrecordedatanintervalof5sor
maximum power)—The maximum energy input rate determi-
less. Steam condensate temperature and weight should be
nation is used to verify that the dishwasher is operating within
recorded at the outlet of the machine. Barometric pressure has
manufacturer specifications. If there is a data plate rating or a
to be recorded for every run or idle performed on the
rating printed on the heating element for the tank heater(s),
dishwasher. Make any necessary corrections to the measure-
followthestepsbelow.Ifthetankheater(s)areincludedaspart
ments as required by the instruments (that is, correction for
ofatotalpowerconsumptiondataplaterating,followthesteps
elevation of pressure gauge above pressure line, etc.).
below while monitoring the total power consumption for all
10.1.5 For each run of every test, confirm that the inlet
components included in the rating.
steam pressure 65% of rated “data plate” pressure. If the
10.5.1 Forgasandsteampowereddishwashers,instruments
difference is greater than 5%, the steam pressure regulator
shall be connected so that the energy (for steam and gas tank
should be adjusted.
heat) consumption of the tank heater is measured separately.
10.2 Booster Temperature Calibration (High Temperature Fillthedishwashertankwithwater.Forgastankheaters,allow
Machines): the tank heater to idle for one “on” cycle to allow the burner
F1920 − 20
orificestoheatup.Commencemonitoringtheelapsedtimeand time and energy consumption of the booster heater during the
energy consumption of the tank heater when the tank heater complete “on” cycle. For steam coil booster heaters, com-
cyclesonforthesecondtime.Stopmonitoringtheelapsedtime mencemonitoringtheelapsedtimeandenergyconsumptionof
and energy consumption of the tank heater when the tank the booster heater when the booster heater cycles on. Stop
heater cycles off. Record the time and energy consumption of monitoring the elapsed time and energy consumption of the
the tank heater during the complete “on” cycle. For steam coil boosterheaterwhenthetankheatercyclesoff.Recordthetime
tank heaters, commence monitoring the elapsed time and and energy consumption of the booster heater during the
energy consumption of the tank heater when the tank heater complete “on” cycle. For machines with steam coil booster
cycles on. Stop monitoring the elapsed time and energy heat,usinganappropriatelysizedvesselthatiscompletelydry,
consumptionofthetankheaterwhenthetankheatercyclesoff. catch all condensate from the outlet during the test. Weigh the
Record the time and energy consumption of the tank heater filled vessel, subtracting the weight of the capture vessel to
during the complete “on” cycle. For machines with steam coil calculate the weight of the condensate. Measure the tempera-
tankheat,usinganappropriatelysizedvesselthatiscompletely ture of the condensate in order to obtain the steam condensate
dry, catch all condensate from the outlet during the test.Weigh density. Calculate the total mass of the inlet steam during the
the filled vessel, subtracting the weight of the capture vessel to test and confirm that it is within 5% of the mass of water
calculate the weight of the water. Calculate the total mass of measured from the outlet stream. If the difference is greater
the inlet steam during the test and confirm that it is within 5% than 5%, adjust the pressure of the inlet steam until the
of the mass of water measured from the outlet stream. If the difference is less than 5% and rerun the booster heater
difference is greater than 5%, adjust the inlet steam pressure “maximum energy input rate” (that is, maximum power) test.
until the difference is less than 5% and rerun the tank heater
10.6.2 Determine the booster “maximum energy input rate”
“maximum energy input rate” (i.e. maximum power) test.
(that is, maximum power) for the dishwasher under test, in
10.5.2 For electric tank heaters, the input rate should be accordance with 11.5. Report the measured input rate and
measured only when the heater element is engaged (no pumps confirm that it is within 5% of the data plate rated input or
or motors working) if there is one meter installed on the rating printed on the heating element. If the difference is
machine, otherwise the tank heater needs to be submetered. greater than 5%, testing shall be terminated.
Commence monitoring the energy to the tank heater when the
10.7 Dishwasher Sanitizing Rinse Water Consumption
tank heater cycles on. Stop monitoring the energy when the
Verification—The sanitizing and post-sanitizing rinse water
tank heater cycles off. In accordance with 11.5, determine the
consumption test shall be run before the washing energy
tank heater “maximum energy input rate” (i.e. maximum
performance test, and the idle energy consumption test. The
power) for the dishwasher under test. Report the measured
Dishwasher shall be operated at the same settings (water level,
input rate and confirm that it is within 5% of the data plate
conveyor speed, sanitizing mode, etc.) for all three tests: the
rated input or rating printed on the heating element. If the
water consumption test, washing energy performance test, and
difference is greater than 5%, testing shall be terminated.
the idle energy consumption tests. Machines with a post-
10.6 Booster Maximum Energy Input Rate (that is, maxi- sanitizing rinse shall separately measure and report the water
mum power): consumption with the feature turned on and turned off. For
fresh water machines, rinse pressure should be set to the
NOTE 8—For some gas appliances, the energy input rate changes as the
manufacturer’s rating 62 psig (613.8 kPa).
burnerorificesheatupfromroomtemperaturetooperationaltemperature.
10.7.1 Activate the sanitizing rinse (and the post-sanitizing
The step described in 10.6.1 is provided to provide a stable test condition.
The dishwasher machines sanitizing rinse cycle is run continuously to
rinseifthewaterconsumptionincludingpost-sanitizingrinseis
initiate and keep the booster heater’s gas burner(s) on during the booster
being measured) for at least one minute. Do not activate any
maximum energy input rate test. If there is a data plate rating or a rating
other component(s) of the Dishwasher that consume fresh
printed on the heating element for the booster heater, follow the steps
water. If there is a lever that actuates the sanitizing rinse or
below. If the booster heater is included as part of a total power
post-sanitizing rinse, the lever may be held down to simulate
consumption rating, follow the steps below while monitoring the total
power consumption for all components included in the rating.
operation,otherwisebacktobackrackscanbesentthroughthe
dishwasher continuously. Verify that the pumped sanitizing
10.6.1 Instruments shall be connected so that only the
rinse and post-sanitizing rinse operate correctly. If they do not,
energy (for gas or steam booster heat) or power (for electric
terminate testing.
booster heat) consumption of the booster heater is measured.
10.7.2 Using a flow meter, measure all water that is sent to
Fill the booster heater with water. For electric booster heaters,
the machine 1 min 6 1 s of continuous operation of the
commence monitoring the power of the booster heater when
sanitizingrinse(andpost-sanitizingrinseifthewaterconsump-
the booster heater cycles on. Stop monitoring the power when
tion including post-sanitizing rinse is being measured). Record
the booster heater cycles off. Record the maximum power
the exact time. Do not activate any other component(s) of the
value as the maximum energy input rate. For gas booster
Dishwasher that consumes water. If there is a lever that
heaters, allow the tank heater to idle for one “on” cycle to
actuates the sanitizing rinse or post-sanitizing rinse, the lever
allowtheburnerorificestoheatup.Commencemonitoringthe
may be held down to simulate operation.
elapsed time and energy consumption of the booster heater
10.7.3 Repeat steps 10.7.1 and 10.7.2 three times.
when the booster heater cycles on for the second time. Stop
monitoring the elapsed time and energy consumption of the 10.7.4 Determine the water consumption, for the dish-
booster heater when the booster heater cycles off. Record the washer under test. Report the measured consumption and
F1920 − 20
confirm that it is within 5 % of the data plate rating. If the heaters to cycle off. If the tank heaters are not cycled on after
differenceisgreaterthan5%,terminatetestingandcontactthe thefifthfullrackhaspassedthroughthemachine,thenwaitfor
manufacturer. The manufacturer may make appropriate the heaters to cycle on then off again.
changes or adjustments to the dishwasher or provide another
10.8.9 Commence monitoring elapsed time, energy of the
unit for testing.
dishwasher and the booster, water consumption, and tempera-
tures of the booster inlet, dishwasher inlet (if using an external
NOTE 9—Some dishwasher machines are equipped with a final rinse
booster), sanitizing rinse and wash tank.Temperatures shall be
catch pan (final rinse water saver) to capture the water from the rinse
cycle. Set the catch pan drain to manufacturer’s recommended setting. measured at a 30-s interval or less. Record the average tank
Report final rinse catch pan drain setting.
temperatures experienced during the washing test period at the
30-s intervals or less. Also record the average final rinse
10.8 Washing Energy Performance Test:
temperature while rinse water is flowing as indicated by the
10.8.1 Thistestwillrequire30(60forflighttype)dishloads
water meter. If the final rinse temperature decreases before the
and two empty dishracks, as described in Sections 6 and 9.
rinse period is over, the external booster heater is undersized.
Recordtheweightofthedishesineachdishloadandtheweight
Ifalargerboosterheaterisunavailable,atankwaterheatercan
of each of the racks, verify that they meet the weight
be used to supply rinse temperature water into the dishwasher.
requirements specified in 9.12.2 and 9.12.3.
10.8.9.1 The booster energy shall be logged separately but
10.8.2 The washing energy performance tests are to be run
simultaneously from the dishwasher energy. If possible, sub-
a minimum of three times. Additional test runs may be
monitor the energy of the booster heater during the washing
necessary to obtain the required precision for the reported test
energy performance test. If the booster heater cannot be
results (see AnnexA1). Each washing energy performance test
sub-monitored, the booster heater energy shall be included as
shall be run in the following sequence:
part of the dishwasher energy.
10.8.2.1 The machine will be conditioned by idling at its
10.8.10 Load the first test rack of dishes into the machine.
operating setpoint for a minimum of 30 minutes followed by
Immediately load the remaining four (nine for flight type)
running two empty dishracks through the machine.
dishloads back-to-back with as little space as possible between
10.8.2.2 Each washing energy performance test replicate
adjacent racks. Do not push the dishloads through the dish-
shall consist of six batches of five dishloads per batch. Flight
washer;allowdishwashertopulltheracksthroughthemachine
type machines will use ten dishloads per batch. The first batch
at the manufacturer-specified conveyance speed.
will be considered a stabilization batch and the remaining five
10.8.11 Remove each dishload when the cyc
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