Optfor better

R-22 Phaseout Spurs
Proactive Refrigeration
System Upgrade
St. Cloud Refrigeration converts Mars
Lakeview Arena in Duluth, Minnesota,
to Chemours non-ozone depleting,
low global warming Opteon™ XP40
(R-449A) refrigerant“ There are approximately 4,800
indoor ice rinks in North America
with an average age over 30 years.”—NHL®
https://www.nhl.com/info/nhl-green/greener-rinks

Situated in Duluth, Minnesota, the Mars Lakeview
Arena had been supporting a full-size ice sheetwith its original 1999 flooded chiller systemcharged with 1,750 pounds of R-22. “Although
the system ran for some time without needing tohave refrigerant added, we knew the potential
was there to have a leak sometime down the road,requiring us to add more R-22 to the system. This
could get costly for our client, given the phaseoutof R-22 in the near future. So, we raised the ideaof a retrofit to find a long-term plan to get awayfrom R-22,” said Justin Zembo, lead mechanicaltechnician from St. Cloud Refrigeration (SCR).

Mars Lakeview Arena at a Glance• Privately owned and operated ice skating arena• Located in Duluth, Minnesota• Built in 1999
• Provides 3,500 hours of ice time toapproximately 120,000 patrons each year
• Serves Division 3 college hockey teams, highschool hockey teams, the Duluth figure skatingclub, and the general public

Brendan Flaherty, the rink’s executive director,
continued,“We really weighed our options when
deciding to replace the R-22 that
we had been using in our chiller with
Opteon™ XP40. Ultimately, Opteon™
was more cost-effective for us thanammonia or other options, and we sawvery early success. The ice quality
has been as good or better since theconversion.”
Like many community rinks, Mars Lakeview Arena
operates year-round and is a social and cultural
hub for area residents. It serves Division 3 college
hockey teams, high school hockey teams, theDuluth figure skating club, and the general public.
The rink provides over 3,500 hours of indoor ice
time to approximately 120,000 patrons each year.

After the arena received a Mighty Ducks grant,
the rink’s executive team, led by Flaherty, decided
to make some much-needed and eco-friendly
facility upgrades. In addition to the chiller retrofit,
the arena purchased an electric Olympia ice
resurfacer and a new dehumidifier system. The
converted direct expansion (DX) chiller systemruns on a non-ozone depleting, low global warming
potential (GWP) refrigerant from Chemours
called Opteon™ XP40 (R-449A). The refrigerant
is a hydrofluoroolefin (HFO) blend that has zeroozone depletion potential (ODP) and provides
a 23% reduction in GWP over R-22. The arena
partnered with technical experts from SCR andThe Chemours Company to discuss equipment andretrofit options.

Conversion Process
After discussing retrofit options for the rink,
SCR began planning, ordering, and assembling
the necessary equipment in December 2016.

Opteon™ XP40 Properties
XP40

HCFC-22

ASHRAE Designation

R-449A

R-22

ASHRAE Safety Classification

A1A1Ozone Depletion Potential

None

0.05

Global Warming Potential

1282

1810

-50.7 °F

-41 °F

Liquid Density at 70 °F, lb/f

69.5

75.3

Lubricant

POE

Mineral Oil

Boiling Point at 1 atm
3

For further data on the properties, uses, safety, and handling ofOpteon™ XP40 (R-449A), please visit www.opteon.com.

Early April 2017 was selected for the retrofit
to accommodate the rink’s schedule, and SCR
planned each detail in advance. On a Sunday
evening, SCR began recovering the R-22 anddrained the system’s secondary coolant, glycol.
Next, SCR removed the flooded R-22 chiller barrel
and replaced it with a DX chiller barrel designed
to run on Opteon™ XP40. They also drained themineral oil out of the system and replaced it withpolyolester (POE) oil. The elastomeric seals andO-rings in valves and other parts of the systemwere also replaced as a precaution againstfuture leaks.
The chiller’s controller had been upgraded toa digital control system a few years prior to
the retrofit. In order to monitor the system’s
performance with the XP40 refrigerant, SCR
added more sensors on the compressors tomonitor temperatures and pressures, andinstalled others on the chiller barrel itself.
They also placed sensors on the glycol side tobetter monitor flow. Finally, SCR updated theexisting leak detector settings to monitor for thenew refrigerant.
With the retrofit complete, the new system’s
footprint in the mechanical room is smaller.
The new evaporator is shorter because the old
one had a surge drum on top that used to reachthe ceiling. “The old system had a lot of flanges
and connection points, which increased thepotential for leaks. The new system is a much
more streamlined design,” explained Zembo. The
old system also required an oil pot that had to bechecked and manually drained, but now with the
new DX barrel, the rink doesn’t require that kind ofmaintenance anymore.

“This job was really successful because we plannedevery detail in advance,” said Zembo. He added,“The chiller ended up being shut down for only
five days, although they had planned for a full weekof downtime.”

Operational and Energy
Efficiency Performance
Brendan Flaherty is happy with the new system.
“The ice sets up very fast now and our wholesystem is more digital, so SCR can monitor it fromtheir offices—this saves us from having to worry
about anything.” Arena staff and ice rink patrons
have also reported excellent ice quality.
Interestingly, the new system is charged withjust 950 pounds of R-449A versus the 1,750
pounds of R-22. This smaller charge size doesn’t
affect the performance of the system, but it does
have several benefits. First, it provides some upfront cost savings to the rink and the contractor
because they’re buying less refrigerant. Second,in the event of a leak, there would be a lower
risk of environmental impact because there isless overall refrigerant. Finally, the total climate
impact potential of the system goes down not
only because of the lower GWP of the refrigerant
itself and the fact that there is less of it, but also
because the new system uses less energy.

While many factors contribute to improvements
in energy efficiency, and SCR cannot guarantee
its clients energy savings in every case, Mars
Lakeview Arena saw an average reduction inits facility electrical usage of ~16% in the six
months immediately following the refrigeration
system upgrades compared to the previous year.

Arena Energy Usage (kWh)
3500
2013

2014

2015

2016

2017 (XP40)

3000

Refrigerant Conversion
April 2017

Avg. kWh

2500

2000

1500

1000

500

0JAN

FEB

MARAPR

MAYJustin Zembo also reports that in the year sincethe retrofit occurred, SCR has not detected anyleaks. There were some small leaks over the years
with the old R-22 system.

Conclusion
The refrigeration system for Mars Lakeview
Arena’s ice rink was successfully converted from
R-22 refrigerant to low GWP refrigerant Opteon™
XP40 (R-449A).
Justin Zembo explains, “While Mars Lakeview
Arena could potentially go to an ammonia system,in that case they’d be replacing everything in theroom.” He added, “They’d also end up spending alot more money and having a lot more businessdisruption and downtime for the rink.”

JUNEJULY

AUG

SEPT

OCTNOVDEC“XP40 was a great option. I don’t knowof a lower GWP option that would havestill used as many of the same systemcomponents as we did.”—Justin Zembo, SCR Team Leader
Brendan Flaherty agrees: “We’re really proud of
our focus on sustainability and we were fortunate
to have good guidance from SCR. It’s a relief not
to have to worry about the R-22 anymore. I highly
recommend doing a retrofit as an alternative
to an entire system replacement—they had theconversion done within a week. It didn’t take longand it wasn’t invasive,” Flaherty concluded.

For more information on the Opteon™ family of low GWP products,
visit optforbetter.com/NHL

The information set forth herein is furnished free of charge and based on technical data that Chemours believes to be reliable. It is intended for use
by persons having technical skill, at their own risk. Because conditions of use are outside our control, Chemours makes no warranties, expressedor 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 arecommendation to infringe, any patents or patent applications.
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