Refrigerant Conversions
for Flooded Systems
Part 1. Commercial Ice Machine
Field Conversion of a Commercial Ice Making
System with a Flooded Evaporator fromR-404A to Opteon™ XP40 (R-449A)

Background

The Project

Many types of refrigeration equipment operatingon pure refrigerant fluids such as R-22 or blends
such as R-507/R-404A with minimal temperature glide, utilize flooded evaporator type heatexchangers. These designs are simple toconstruct and operate efficiently for pure or nearazeotropic fluids. Owners of these types ofsystems are challenged to find service refrigerant
since the production (or import) of virgin R-22 is
no longer permitted and high GWP refrigerants
like R-507 and R-404A are being phased downwith availability of reclaimed refrigerant limited
and subject to price volatility.

A project was undertaken to understand the requirements to convert, and subsequently monitor theperformance of a commercial refrigeration system(ice making), originally designed with R-404A after
changing over to run on a more environmentally
sustainable (non ODP, lower GWP) refrigerant blend(R-449A). The system was owned by an ice machineservice vendor and the test was performed on sitewith engineering support from Chemours.

While there is no “drop-In” product that will
perform identically to R-22 (or R-404A / R-507),
the successful conversion of flooded systems
using Opteon™ XP40 (R-449A), a non-ozone
depleting, lower GWP, HFO blend refrigerant has
been demonstrated.
This report summarizes the details of the conversion of a commercially available ice-makermachine from R-404A to Opteon™ XP40(R-449A). While the system in this study is very
typical of many others, there can be differencesin design, system condition, and operating
factors that make each system somewhat unique.
Prior to attempting a field conversion, a detailed
engineering analysis of the system is required.

The goals of this project were three-fold:
1. Determine the steps and changes necessary toconvert the system from R-404A to R-449A
2. Evaluate the performance (ice production) of thesystem after the conversion to R-449A andimpacts on operating conditions (pressures,temperatures, amp draw, oil, etc.)
3. Study the refrigerant blend composition during
operation at several points around the system toassess the impact of temperature glide.

The System
The system in this study was a nominal 5-ton commercial ice making system (Vogt M#P118), severaldecades old. The unit was operating on R-404A
refrigerant with a flooded evaporator equipped witha Sporlan EBSSE-10-C TEV and a water-cooledcondenser. The compressor was a Carlyle
06DM337D13250 with POE lubricant.

Refrigerant Conversions for Flooded Systems - Part 1. Commercial Ice Machine2

Conversion Process

System Observations
During Testing

The following steps were used converting anice-maker machine from R-404A to Opteon™
XP40 (R-449A):• The existing R-404A was recovered prior tocharging the system with ~ 300 lbs. ofR-449A. The system was started up andallowed to stabilize for a preliminary assessment using the existing power element(R-404A) on the TEV (thermal expansion
valve). Measured capacity in this configuration was approximately 93% of the nominal 5
ton rating.
• Adjustments to the TEV (opening) resulted inslightly increased capacity. The receiverliquid level after the harvest cycle wasobserved to be lower than the operational
level and fell below the sight glass at the endof the freeze cycle.
• To further investigate the effect of expansion
valve selection on system capacity, an R-22
element was installed. Results indicated theoriginal R-404A power element was theoptimum choice for this application. As aresult, the remainder of the testing wasconducted with the R-404A element• On the second testing day, an additional
25lbs of R-449A refrigerant was added toraise the refrigerant level in the evaporator
and receiver. Four hours post refrigerant
addition, ice production was measured to be10,982 lbs (110%).
• Further tuning of the TEV resulted in production batches of 11, 073 lbs. (111%) and
11,242 lbs. (112%) with liquid level clearlyvisible in the receiver sight glass during bothfreeze cycles.

The conversion to Opteon™ XP40 (R-449A)
resulted in the following observations:• Compressor oil management was good.
Slight oil foaming was observed at the startof the freeze cycle with the site glass
approximately half clear mid cycle and at theend of the freeze cycle.
• Compressor Amp Draw (averaged over threecycles)- L1 44.8 amps
- L2 46.5 amps
- L3 46.7 amps
• Compressor Suction P: average 40 psig at
end of freeze cycle• Compressor Suction P: average 77 psig at
harvest cycle• Compressor Superheat: average 26°F at
end of freeze cycle• Discharge Pressure: average 245 psig atstart, average 242 psig at end of freezecycle• Discharge Temp: 137°F @ freeze cycle
start, 165°F @ freeze cycle end• Liquid Subcooling: average 30-35°F @ TEV• Water make-up Temperature: ~52° F

Refrigerants
Table 1. below contains a brief comparison of the refrigerant properties.

Table 1. Refrigerant Properties
R-404A

R-449A

R-125/R-143a/R-134a

R-32/R-125/R-134a/R-1234yf

44/52/4

24.3/24.7/25.7/25.3

Safety ClassA1

A1GWP

3922

1397

Temp Glide~1 R~7 RComponents
Weight %Refrigerant Conversions for Flooded Systems - Part 1. Commercial Ice Machine3Refrigerant Analysis

Sample points #1-3 are all expected to be the same
composition as there is nothing in the systemarchitecture that would cause fractionation
between these points. For example, comparing thetheoretically predicted wt. % of the R-32 component at 27.6 wt. % to the measured values of 27.1,27.4, and 26.8 wt. % from samples #1-3, shows
very good agreement between the model andsamples.

Refrigerant samples were obtained from variouspoints in the system (see Figure 1) and returned toChemours central research facility for compositional analysis via Gas Chromatography. The results
are presented in Table 2 below.
All samples were analyzed in triplicate with theaverage of three GC runs reported in the table.
Predicted compositions of the R-449A at thevarious sample points were calculated based on a
proprietary VLE model using the R-449A refrigerant blend properties and the system components,design, and operating conditions during the test.

Figure 1. Schematic of Ice Machine Components andRefrigerant Sample Points

As expected, the bulk refrigerant circulating within
the system differs slightly from the nominal composition as delivered in the virgin refrigerant cylinder
due to the temperature glide and the local vapor
liquid equilibrium interactions within the variouscomponents.

Sample #2

Flooded Evaporator

WaterTubes

HXTEV

Sample #5

Sample #3

Sample #1

Sample #4

Overall, the analytical results are in good agreement with the expected compositions, in mostcases within 1-2 wt. %.

Compressor

Ice
HarvestReceiver

Table 2. GC Analysis and Model Predictions of Refrigerant Samples

Refrigerant Composition, wt %Field Test Samples

Model Predictions

R-32

R-125

R-134aR-1234yf

R-32

R-125

R-134aR-1234yf

24.3

24.7

25.7

25.3

24.3

24.7

25.7

25.3

#1 Compressor Discharge

27.1

27.1

22.5

23.6

27.6

26.5

22.2

23.8

#2 Condenser, entering vapor

27.4

27.3

22.1

23.3

27.6

26.5

22.2

23.8

#3 Condenser, leaving liquid

26.8

27.14

22.5

23.6

27.6

26.5

22.2

23.8

#4 Evaporator inlet, liq

26.2

26.8

23.0

24.0

23.3

24.9

25.9

25.9

#4 Evaporator inlet, vap

36.5

30.7

14.8

18.0

36.9

29.8

14.1

19.2

#5 Compressor Suction

27.3

27.2

22.1

23.4

27.6

26.5

22.2

23.8

R-449A, Nominal
Sample Points

Refrigerant Conversions for Flooded Systems - Part 1. Commercial Ice Machine4While most of the sample points were at system
locations where only one phase (either pure vapor
or pure liquid) was present, it is noted that sample
point #4, the inlet to the flooded evaporator shell
was a mixture of both liquid and vapor, which ismore challenging in terms of sampling and interpretation of results.
Based on the small differences in both the low
and high side compositions from the field measurements to the nominal R-449A composition,it’s not surprising the system performed quite
well post conversion based on the well-established performance match of R-449A to R-404A
in DX systems.

Conclusion:
As stated in the introduction, flooded systems arestill operating today with R-22, R-404A, or R-507
refrigerants. Information on the performance ofalternative refrigerants has been limited to date,however recently Opteon™ XP40 (R-449A) has
been shown to successfully operate in certain
systems following a detailed engineering analysis.
For further guidance please contact your local
Chemours representative or visit opteon.com totalk to one of our Technical Service engineers.

Summary of Testing Results
Below is a summary of the system performance
results following the conversion to Opteon™
XP40 (R-449A):• Successful operation of a Vogt ice machinewith a flooded evaporator design (originallyR-404A) after conversion to low GWP blend
R-449A was demonstrated• Capacity (ice production) of ~ 112% compared to name plate (5-ton) capacity wasachieved• No component changes were required,however, adjustments to the existing TEV
setting as well as refrigerant charge werecritical to optimize performance• No oil management issues noted while operating with original POE oil after conversion• Suction/Discharge pressures, superheat,subcooling and discharge temperatures were
all within system design limits• Compositional analysis of refrigerant showedminor shifts in composition as refrigerantcirculated throughout the system, in good
agreement with thermodynamic models.

Refrigerant Conversions for Flooded Systems - Part 1. Commercial Ice Machine5About Opteon™ Refrigerants
The Opteon™ refrigerants portfolio offers the optimal balance of environmental sustainability, performance, safety, and cost to help meetboth regulations and business goals.

refrigerant generations.

savings over the system’s life.

global and local regulatory standards.
Minimizing conversion costs and downtime.

technologies.

experience, Chemours refrigerant experts
can help customers achieve both complianceand peak performance.

Visit Opteon.com/regulations for more information on HFC replacements or contact our experts.

The information set forth herein is furnished free of charge and based on technical data that Chemours believes to be reliable. It is intended foruse by persons having technical skill, at their own risk. Since conditions of use are outside of Chemours’ control, Chemours makes no warranties,
expressed or implied, and assumes no liability in connection with any use of this information. Nothing herein is to be taken as a license to operate
under, or a recommendation to infringe, any patents or patent applications. NO PART OF THIS MATERIAL MAY BE REPRODUCED, STORED IN
A RETRIEVAL SYSTEM OR TRANSMITTED IN ANY FORM OR BY ANY MEANS WHETHER ELECTRONIC, MECHANICAL, PHOTOCOPYING,RECORDING OR OTHERWISE WITHOUT THE PRIOR WRITTEN PERMISSION OF CHEMOURS. FOR MORE INFORMATION, VISIT
WWW.OPTEON.COM.
© 2023 The Chemours Company FC, LLC. Opteon™, Freon™ and any associated logos are trademarks or copyrights of The Chemours CompanyFC, LLC. Chemours™ and the Chemours Logo are trademarks of The Chemours Company.
O-RCFSP1 (4/23)

Refrigerant Conversions for Flooded Systems - Part 1. Commercial Ice Machine6