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Food Service Technology Center

KE2 Therm Solutions EvaporatorEfficiency Refrigeration Controller Case Study Test Report FSTC Report # 501311392-R0

August 2015

Prepared by: Angelo Karas

Contributors: Don Fisher Denis Livchak David Zabrowski Fisher-Nickel, Inc.

Prepared for:

Pacific Gas and Electric Company Customer Energy Efficiency Programs

PO Box 770000 San Francisco, California 94177

Pacific Gas and Electric Company Food Service Technology Center. All rights reserved. 2015

KE2 EvaporatorEfficiency Refrigeration Controller

Case Study Test Report

Food Service Technology Center Background The information in this report is based on data generated at the Pacific Gas and Electric Company (PG&E) Food Service Technology Center (FSTC). Dedicated to the advancement of the foodservice industry, The FSTC has focused on the development of standard test methods for commercial foodservice equipment since 1987. The primary component of the FSTC is a 10,000 square-foot laboratory equipped with energy monitoring and data acquisition hardware, 60 linear feet of canopy exhaust hoods integrated with utility distribution systems, equipment setup and storage areas, and a state-of-the-art demonstration and training facility.

The FSTC Energy Efficiency for Foodservice Program is funded by California utility customers and administered by PG&E under the auspices of the California Public Utilities Commission (CPUC). California customers are not obligated to purchase any additional services offered by the contractor.

Policy on the Use of Food Service Technology Center Test Results and Other Related Information Fisher-Nickel, Inc. and the FSTC do not endorse particular products or services from any specific manufacturer or service provider.

The FSTC is strongly committed to testing foodservice equipment using the best available scientific techniques and instrumentation.

The FSTC is neutral as to fuel and energy source. It does not, in any way, encourage or promote the use of any fuel or energy source nor does it endorse any of the equipment tested at the FSTC.

FSTC test results are made available to the general public through technical research reports and publications and are protected under U.S. and international copyright laws.

Disclaimer Copyright 2015 Pacific Gas and Electric Company Food Service Technology Center. All rights reserved. Reproduction or distribution of the whole or any part of the contents of this document without written permission of FSTC is prohibited. Results relate only to the item(s) tested. Neither Fisher-Nickel, Inc., PG&E nor any of their employees, or the FSTC, make any warranty, expressed or implied, or assume any legal liability of responsibility for the accuracy, completeness, or usefulness of any data, information, method, product or process disclosed in this document, or represents that its use will not infringe any privately-owned rights, including but not limited to, patents, trademarks, or copyrights.

Reference to specific products or manufacturers is not an endorsement of that product or manufacturer by Fisher-Nickel, Inc., the FSTC, or PG&E. In no event will Fisher-Nickel, Inc. or PG&E be liable for any special, incidental, consequential, indirect, or similar damages, including but not limited to lost profits, lost market share, lost savings, lost data, increased cost of production, or any other damages arising out of the use of the data or the interpretation of the data presented in this report.

Retention of this consulting firm by PG&E to develop this report does not constitute endorsement by PG&E for any work performed other than that specified in the scope of this project.

Legal Notice This report was prepared as a result of work sponsored by the California Public Utilities Commission (CPUC). It does not necessarily represent the views of the CPUC, its employees, or the State of California. The CPUC, the State of California, its employees, contractors, and subcontractors make no warranty, express or implied, and assume no legal liability for the information in this report; nor does any party represent that the use of this information will not infringe upon privately owned rights. This report has not been approved or disapproved by the CPUC nor has the CPUC passed upon the accuracy or adequacy of the information in this report.

Revision History

Revision num. Date Description Author(s)

0 Aug 2015 Initial Release A. Karas

FSTC Report # 501311392-R0 12949 Alcosta Blvd. Suite 101, San Ramon, CA 94583 P: 1.800.398.3782 F: 1.925.866.2864 www.fishnick.com

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Contents

Executive Summary ...................................................................................................................................................... 5 Introduction ................................................................................................................................................................... 7 Objectives and Scope ................................................................................................................................................... 7 Equipment Description ................................................................................................................................................. 7 Procedure ...................................................................................................................................................................... 9

Approach .................................................................................................................................................................... 9 Setup and Instrumentation .......................................................................................................................................... 9

Results ......................................................................................................................................................................... 14 Operational Comparison ........................................................................................................................................... 14 Energy Use Comparison ........................................................................................................................................... 18

Conclusions, Observations and Recommendations ............................................................................................... 21 Appendix A: General Product Information ............................................................................................................... 22 Appendix B: Setpoints Menu Table ........................................................................................................................... 26 Appendix C: KE2 Evap v4.0 with Smart Access ....................................................................................................... 28 Appendix D: KE2 MasterView Overview ................................................................................................................... 30 Addendum: Report Certification ................................................................................................................................ 38


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Figures Figure 1: KE2 Evaporator Efficiency Controller ............................................................................................................... 8 Figure 2: KE2 Evap Configuration Setpoints—Baseline Emulation Mode ..................................................................... 11 Figure 3: KE2 Evap Configuration Setpoints—KE2 Evap Mode ................................................................................... 12 Figure 4: Operation Profile with Original Mechanical Controls ...................................................................................... 14 Figure 5: Baseline Emulation Mode Operation Profile .................................................................................................. 15 Figure 6: KE2 Evap Mode Operation Profile ................................................................................................................. 15 Figure 7: Baseline Emulation Mode Operation Profile—Zoomed .................................................................................. 17 Figure 8: KE2 Evap Mode Operation Profile—Zoomed................................................................................................. 17 Figure 9: Evaporator Unit Daily Energy vs. Outdoor Ambient Temperature .................................................................. 19 Figure 10: Baseline Emulation Mode: Combined Daily Energy vs. Outdoor Ambient Temperature .............................. 19 Figure 11: KE2 Evap Mode: Combined Daily Energy vs. Outdoor Ambient Temperature ............................................ 20

Tables

Table ES-1: Results Summary ........................................................................................................................................ 5 Table 1: Configuration Parameter Setpoints ................................................................................................................. 13 Table 2: Results Summary ............................................................................................................................................ 14


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Executive Summary

With an ever-increasing interest in technologies that can reduce refrigeration energy consumption and optimize

system performance, the Food Service Technology Center (FSTC) evaluated the KE2 Therm Solutions KE2

EvaporatorEfficiency (KE2 Evap) refrigeration controller, a system that replaces the mechanical control

components of a conventional walk-in refrigeration system with electronic temperature sensors and computerized

control hardware designed to optimize the compressor and defrost cycles for best performance with the least

energy consumption. The auto-tuning, adaptive controller applies proprietary algorithms using air and evaporator

coil temperatures together with the refrigeration system response to determine optimum evaporator fan

management, compressor cycling, demand defrost initiation, and defrost heating control and termination.

The evaluation was conducted on a case-study basis using the FSTC’s 50-sq. ft. lab-use, walk-in freezer to

compare the energy use and performance of the preexisting mechanically-controlled system to that of the

retrofitted system using the KE2 Evap controls. Energy consumption was recorded using a power logger installed

in the electrical service panel, and refrigeration temperatures were recorded using the KE2 Evap system hardware

and its on-board logging capability. Because the retrofit was not readily reversible, the mechanical control system

was first monitored to establish baseline operation and then emulated by the KE2 Evap system itself (by setting

parameter variables to mimic the mechanical controls). This method allowed testing to alternate between the

Baseline Emulation Mode and the KE2 Evap Mode through an extended monitoring period spanning six months

in an effort to normalize the varying operating conditions and usage patterns of the test freezer.

Application of the KE2 Evap controller resulted in substantially fewer defrost cycles and an appreciable reduction

in energy use. The defrost frequency decreased from three per day to an average of one every 30 hours, and the

evaporator and condensing unit combined energy use decreased from 40.9 kWh/d to 34.6 kWh/d, representing a

6.3 kWh/d (15 %) reduction. These results are summarized in Table ES-1.

Table ES-1: Results Summary

Baseline Emulation Mode KE2 Evap Mode

Average Defrost Interval (h) 8 30

Average Energy Use (kWh/d) 40.9 34.6

Average Energy Use Reduction (kWh/d) 6.3

Percentage Reduction 15.4%

While the results of this case study may be representative of those expected in similar installations, because the

KE2 Evap can be installed on a wide range of refrigeration systems, the absolute and relative energy reduction will

vary with the system size and type. Furthermore, the overall condition and usage level of a particular refrigeration

system can affect the potential energy saving contribution of the KE2 Evap. In this case study, the FSTC lab


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storage freezer was well-maintained and used relatively lightly, and it was configured to defrost three times a day

instead of the commonly selected four per day. Typical systems in the field will have greater savings potential

based on a higher number of scheduled defrost cycles and more demanding conditions for the refrigeration

equipment.

Overall, the KE2 Therm Evaporator Efficiency controller demonstrated effective reduction in energy use while

improving system performance of the test freezer. In addition to the energy reduction derived from fewer defrosts

and the adaptive control of the evaporator fans and compressor, an added performance benefit of the refined

defrost heat control was the elimination of preexisting frost and ice build-up within the freezer interior that had

resulted mostly from defrost cycle overheating and the accompanying steam that would refreeze on cold surfaces.

Other advantages of the controller are the monitoring, alarm and diagnostic capabilities, which can be used by end-

users and service-personnel alike. Potentially supplementing the direct energy saving of the system, these

supervisory functions provide the ability to identify and correct problems that would otherwise waste energy.


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Introduction Refrigeration energy consumption comprises a significant portion of the total energy usage in foodservice,

particularly with respect to the constant base load. Utilities and end-users alike have become increasingly

interested in emerging technologies that can reduce refrigeration energy consumption and optimize system

performance. The Food Service Technology Center (FSTC) was presented with the opportunity to evaluate the

KE2 Therm Solutions KE2 Evaporator Efficiency (KE2 Evap) refrigeration controller, a system that replaces

conventional mechanical control components, including the thermostat and conventional defrost controls, with

electronic temperature sensors and computerized controls that are designed to optimize the efficiency of the

refrigeration system through compressor, fan, and defrost management for the best performance with the least

energy consumption.

Objectives and Scope The objective of this study was to examine the operation and performance of a KE2 Evap system retrofitted onto a

walk-in freezer originally equipped with standard mechanical controls. The test scope was limited to a case-study

level of evaluation using the lab-storage freezer located at the FSTC. Essentially, it was a field test with no

attempt to control the loading or door openings during the monitoring period. Testing comprised basic

temperature and energy use measurements with as-encountered fluctuating conditions, including ambient

temperatures and humidity, random food product loading, and door openings.

Equipment Description The KE2 Evap system includes the controller, sensors and associated hardware required to completely replace

conventional mechanical evaporator controls, including the thermostat assembly, defrost timer, and defrost

termination switch. It can be installed on a wide range of refrigeration systems, from small walk-ins to large

refrigerated warehouses. The auto-tuning, adaptive controller uses proprietary algorithms for demand defrost

initiation and termination, and for evaporator fan and compressor cycling, based on the air and coil temperatures

and the refrigeration system response. Furthermore, the defrost heat energy (on electric heater systems) can be

modulated to prevent overheating of the elements, which can result in excessive steam that can condense and

freeze onto cold surfaces such as walls and ceilings.

Optionally, the controller can drive an electronic expansion valve (EEV) for precise superheat temperature

management, though an EEV was not installed for this test. Due to the additional installation complexities that

would have required evacuating the refrigerant, replacing the existing thermostatic valve with the EEV, and then


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recharging the system, the evaluation of the additional savings that could be derived from an EEV in combination

with the KE2 Evap was considered beyond the scope of this study.

The KE2 Evap controller can be monitored and configured using the onboard display and keypad or using

standard TCP/IP Ethernet communication protocol through a web browser and computer either connected

directly, through a local network, or with remote communication via the Internet. The system can be configured to

provide alarm notification for exceeded parameters such as high or low air temperature, excessive or prolonged

defrosts or prolonged open-door time. Additionally, the KE2 Evap controller includes on-board data logging

capability, and, through the use of a software application, the data can be streamed to a computer for external

logging as well. This logging arrangement was utilized to record all refrigeration system operation and

measurements throughout this study.

A detailed description of the KE2 Evap system with an explanation of its operation and capabilities is contained

in the manufacturer’s General Product Information document presented in Appendix A, and a more in-depth

explanation is contained in the Theory of Operation T.1.1 document available at the manufacturer’s website at

www.ke2therm.com. Figure 1 shows the KE2 Evap controller mounted to the FSTC walk-in freezer.

Figure 1: KE2 Evaporator Efficiency Controller


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Procedure Approach

Comparative refrigeration system monitoring in case-study or real-world scenarios presents difficulties because

alterations involving dedicated hardware changes to a system typically cannot be readily reversed in order to

switch to and from systems for back-and-forth comparison, and at the same time, operating conditions such as

product loading and outdoor ambient temperatures can fluctuate significantly, thereby skewing the results. For

this evaluation, albeit initiated as a case study, best efforts were made in the system configuration stages to match

internal freezer room (internal air) temperatures and in the data analysis phase to normalize the energy data

affected by usage and environmental condition differences.

Testing was conducted in three phases. First, the preexisting mechanically-controlled system was monitored to

determine baseline conditions such as freezer room temperature, room air temperature differential, defrost

frequency, defrost duration, and defrost termination temperature. Then the freezer was operated using the KE2

Evap controller configured via the parameter settings to emulate the baseline operation of the mechanical controls.

Subsequently, the KE2 Evap controller was configured using the manufacturer-recommended setpoints to achieve

optimal operation as intended. This scheme allowed testing to alternate between the Baseline Emulation Mode

and the optimal KE2 Evap Mode through an extended monitoring period. Test modes were alternated every two-

to-three weeks over a six-month period.

Setup and Instrumentation

The FSTC lab walk-in freezer that served as the basis for evaluating the performance of the KE2 Evap comprised

a box with overall dimensions of 6ʹ × 8ʹ × 7ʹ7ʺ with a 29ʺ × 80ʺ door, and a refrigeration system with a 1.5 HP

outdoor condensing unit and an evaporator unit equipped with two ECM (electronically commutated motor) fans.

The freezer is operated in a temperature controlled lab space and is used to store food product used for cooking

appliance tests.

KE2 Therm Solutions personnel and FSTC researchers installed the KE2 Evap controller system and associated

hardware in two stages. Initially, the controller and included coil and air temperature sensors were installed on the

existing mechanically-controlled system and were used solely for monitoring and data logging during the

preliminary baseline evaluation without altering the mechanical thermostat and defrost timer controls or affecting

their function.

Following the initial baseline monitoring period, the original evaporator control components and wiring

(thermostat, defrost timer and defrost termination temperature switch) were disconnected, and the wiring for the

defrost heater, fan solenoid and liquid line solenoid was all rerouted to the KE2 Evap controller. Additionally, a


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door switch was installed and wired to the controller, which was programmed to turn the evaporator fans off to

minimize air infiltration whenever the door was open.

By analyzing the baseline temperature, compressor cycles, and defrost patterns exhibited with the mechanical

controls, the parameter settings required to configure the KE2 Evap controller for the Baseline Emulation Mode

were determined. Configuration settings included average room temperature, defrost frequency and duration, and

the evaporator temperature at defrost termination. The appropriate settings were programmed into the controller

using the web browser graphical user interface through a computer. Figures 2 and 3 show the interface screen

images of the Setpoints page used to configure the various parameters for the Baseline Emulation Mode and KE2

Evap Mode respectively. Aside from the room temperature setpoint, the KE2 Evap Mode settings were left on the

factory default values. Table 1 highlights the key setting differences between the two modes. Appendix B

contains the Setpoints Menu table, which details all the configuration parameters.

Electrical energy of the condensing and evaporator units was monitored with a Dent Instruments ELITEpro SP

data logger installed in the circuit breaker panel. Refrigeration data points were monitored by the KE2 Evap

system directly and recorded onto a computer using a software utility to stream the data from the controller.

Electrical data and all KE2 Evap system data were recorded at 15-second intervals. Outdoor ambient (condenser)

temperature was monitored with an Internet-linked weather station located on the FSTC roof and the daily

average temperature data was retrieved via the Internet.


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Figure 2: KE2 Evap Configuration Setpoints—Baseline Emulation Mode


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Figure 3: KE2 Evap Configuration Setpoints—KE2 Evap Mode


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Table 1: Configuration Parameter Setpoints


Room (Internal Air) Temperature (°F) -6.5 -5.0

Air Temperature Differential (°F) 5.0 1.0

Refrigeration Fan Mode Permanent On w/ Compressor

Defrost Termination Temperature (°F) 87.0 50.0

Defrost Parameter (min) 25 automatic

Drain Time (min) 0 2

Fan Delay Temperature (°F) 35.0 20.0

Maximum Fan Delay Time (min) 0 2

Defrost Mode Schedule Demand

Electric Defrost Mode Permanent Pulse

Defrost Per Day 3 automatic

Digital Input 1 Mode Disabled Door Switch


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Results Operational Comparison

Following are graphs showing the temperature profiles of the Mechanical Control baseline, Baseline Emulation

Mode, and KE2 Evap Mode configurations. The room (internal air) temperature sensor was located behind the

evaporator in the return air stream, and the coil temperature sensor was inserted into the evaporator coil between

cooling fins. Weekend data periods with no lab activity were selected to provide a clear representation of each

system operation without the effects of variable product loading or door openings. Figure 4 illustrates the baseline

temperature profile of the original mechanical control, and Figures 5 and 6 depict the temperature profiles of the

Baseline Emulation Mode and KE2 Evap Mode, respectively.

The maximum temperature differential parameter setting allowed by the KE2 Evap system was 5°F as compared

to mechanical thermostat effective temperature differential of 7°F. Consequently, the emulation mode operated

with somewhat shorter, more-frequent compressor cycles with a smaller temperature swing, but overall, the

emulation mode provided a close approximation of the preexisting mechanical controls. Note that the average

room temperature in the emulation mode was slightly lower than that of the mechanical-control configuration as

the setpoint was decreased by 5°F due to specific lab requirements during the monitoring period. This adjustment

did not affect the operative quantitative comparison between the Baseline Emulation and KE2 Evap Modes.

Figure 4: Operation Profile with Original Mechanical Controls


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Figure 5: Baseline Emulation Mode Operation Profile

Figure 6: KE2 Evap Mode Operation Profile


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Obvious temperature profile and defrost cycle differences between the emulated baseline mode and the KE2 Evap

mode were immediately evident upon review of the data. Once configured to KE2 Evap Mode, the system

operated with considerably fewer defrosts, shorter defrost durations, and lower peak defrost temperatures at the

coil and in the room. The defrost interval increased from the mechanical defrost timer setting of once every

8 hours to a demand-defrost average of once every 30 hours. Due to a lower KE2 Evap Mode default temperature

differential setting of 1°F, the refrigeration cycles occurred more frequently, increasing from about four cycles per

hour to about eight per hour, which resulted in a smaller effective room temperature differential of 2°F.

Furthermore, the coil temperature exhibited a larger temperature differential, which was indicative of the

evaporator fan cycle modulation algorithm designed to harvest more energy from the coil. The 50°F defrost

termination (coil) temperature setting was sufficient enough to keep the coil free of frost build up, and the

resultant peak room temperature during defrost decreased by 12°F, which resulted in a 9-minute quicker

temperature pull-down recovery rate.

Establishing average room temperature equivalence between the test modes was crucial for the energy

consumption comparison because energy use is especially dependent on the temperature setpoint. Although

periods of steady-state operation, i.e., periods with no door opening or product loading, exhibited comparable

temperatures between the Baseline Emulation and KE2 Evap modes, the temperature profiles varied considerably

during typical days of active freezer usage. The differences in system response and temperature control

(especially during the defrost period and the following cycle) combined with random loading and usage during

the monitoring period created a significant challenge to determine whether the effective temperature setpoints in

each mode were equivalent. Care was taken to closely match the average temperatures by iteratively adjusting the

setpoints accordingly during preliminary test trial days. It was determined upon data compilation that in KE2

Evap Mode, the freezer operated with a 0.9°F lower overall average room temperature and a 0.4°F lower average

room temperature when excluding the defrost periods.

Figures 7 and 8 show operation profiles zoomed in on a 3-hr time frame centered around a defrost cycle and

include the compressor and the evaporator fan cycle profiles. The KE2 Evap temperature profile shows a coil

temperature dip after each compressor cycle, highlighting the effect of the adaptive evaporator fan timing.

Additionally, the quicker temperature recovery after the shorter defrost cycle can be seen more clearly.

The refined defrost control applies pulsed heater energy (visible in the KE2 Evap coil temperature profile in

Figure 8) to prevent overheating and the resultant steam that can condense and refreeze onto cold surfaces. This

refreezing has a compounding effect on evaporator coil frost because there is continuously more moisture

sublimating into the air and then frosting back onto the coil. Using the KE2 Evap resulted in the elimination of

preexisting frost and ice build-up within the freezer interior, which historically had varying levels of accumulation

on the ceiling, walls and floor. After sustained KE2 Evap operation, there was practically none remaining

anywhere within the freezer interior, even after some prolonged periods of heavy freezer usage.


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Figure 7: Baseline Emulation Mode Operation Profile—Zoomed

Figure 8: KE2 Evap Mode Operation Profile—Zoomed


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Energy Use Comparison

The condensing and evaporator unit energy consumption was totaled for each day in each test mode. While

subtracting days used for mode transitions and for temperature adjustment, the data set includes 72 days of

Baseline Emulation Mode testing and 127 days of KE2 Evap Mode testing. Since there was substantial variation

in daily energy use due to environmental condition differences, particularly from day-to-day due to the variability

in freezer activity and loading, a larger set of data was collected to establish more confidence in the average for

each mode.

The following figures show plots of daily energy consumption as a function of daily average outdoor ambient

temperature. Figure 9 shows the daily evaporator energy in each test mode, and Figures 10 and 11 show the

combined condensing and evaporator unit daily energy for the Baseline Emulation Mode and KE2 Evap Mode

respectively. Although the energy variability due to ambient conditions and freezer usage could not be directly

accounted for, the overall average energy consumption was 40.9 kWh/d in the Baseline Emulation Mode and 34.6

kWh/d in the KE2 Evap Mode, translating to a 6.3 kWh/d, 15.4% reduction.

Considering that the fluctuating test conditions caused substantial daily energy use variability and therefore a high

degree of uncertainty in the average energy consumption calculation, the data were further analyzed in an effort to

normalize the energy use estimates. While observing the combined daily energy vs. ambient temperature plots,

the lower data points relative to a given temperature represent the days in which there was little or no freezer

activity, i.e., stable conditions similar to a controlled test scenario. The majority of data points are tightly grouped

near this lower portion of data, and the data points above the median represent most of the usage variability.

A graphically-estimated base energy use trend line (simulating steady state controlled testing) was established for

each test mode plot, and at a normalization point of 60°F, the yearly average temperature at the test location, a

vertical line was intersected with the trend line to establish a nominal average daily energy use. The normalized

values were 39 kWh/d for the Baseline Emulation Mode and 33 kWh/d for the KE2 Evap Mode, which translated

to an energy reduction of 6 kWh/d or 15%. Since this correlated well with the reduction calculated using the

overall averages, the results were considered acceptable within the scope of this study, and hence the averages

were quoted for straightforwardness. The trend lines and normalization point intersection lines are included in

Figures 10 and 11. Table 2 summarizes the monitoring results. Note that in KE2 Evap Mode, the freezer operated

with a 0.9°F lower overall average room temperature and a 0.4°F lower average room temperature when

excluding the defrost periods, which ultimately would tend to result in a more conservative energy reduction

estimate.


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Figure 9: Evaporator Unit Daily Energy vs. Outdoor Ambient Temperature

Figure 10: Baseline Emulation Mode: Combined Daily Energy vs. Outdoor Ambient Temperature


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Figure 11: KE2 Evap Mode: Combined Daily Energy vs. Outdoor Ambient Temperature

Table 2: Results Summary


Overall Average Room Temperature (°F) -2.5 -3.4

Average Room Temperature Excluding Defrost Periods (°F) -3.5 -3.9

Average Outdoor Ambient Temperature (°F) 58.4 56.0

Average Defrost Interval (h) 8 30

Days Monitored 72 127

Condensing Unit Average Energy Use (kWh/d) 35.9 31.8

Evaporator Unit Average Energy Use (kWh/d) 5.0 2.8

Combined Average Energy Use (kWh/d) 40.9 34.6

Combined Average Energy Use Reduction (kWh/d) 6.3

Percentage Reduction 15.4%


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Conclusions, Observations and Recommendations In summary, the KE2 Therm Evaporator Efficiency controller demonstrated an appreciable reduction in energy

use while improving the freezer system performance. In addition to the nominal 15% energy reduction derived

from fewer defrosts and the adaptive control of the evaporator fans and compressor, the system operated with

more precise temperature control with smaller swings, and a lower peak defrost temperature. Furthermore, an

added performance benefit of the refined defrost control, which applies pulsed heat energy to prevent overheating

and the resultant steam, was the complete elimination of the preexisting frost and ice build-up within the freezer

interior, which historically had varying levels of accumulation on the ceiling, walls, and floor.

It is important to note that while the results of this case study may be representative of those expected in similar

installations, because the KE2 Evap can be employed on a wide range of refrigeration systems, the absolute and

relative energy reduction and system payback will vary with the system size and type. Furthermore, the overall

condition and usage level of a particular refrigeration system can affect the potential energy saving contribution of

the KE2 Evap. In this case study, the FSTC lab storage freezer was well-maintained, used relatively lightly, and

configured to defrost three times a day instead of the commonly selected four per day. Typical systems in the field

will have greater savings potential based on a higher number of scheduled defrost cycles and more demanding

conditions for the refrigeration equipment.

Other advantages of the controller are the monitoring, alarm, and diagnostic capabilities, which can be used by

end-users and service personnel alike. As such, the supervisory functions and the ability to readily identify and

correct problems can supplement the direct energy saving by preventing energy-wasting malfunctions. Overall, the

KE2 Evap would be an excellent addition to a refrigeration system.


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Appendix A: General Product Information


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Appendix A: General Product Information (Continued)


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Appendix B: Setpoints Menu Table


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Appendix B: Setpoints Menu Table (Continued)


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Appendix C: KE2 Evap v4.0 with Smart Access


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Appendix C: KE2 Evap v4.0 with Smart Access (Continued)


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Appendix D: KE2 MasterView Overview


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Appendix D: KE2 MasterView Overview (Continued)


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