1. R32 refrigerant
Installation & Design aspects
Hilde Dhont, Daikin Europe N.V.
Environment Research Center
Mostra Convegno 2014
Copyright Daikin
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2. Typical refrigerants used today in stationary
air conditioning & heat pumps
R410A : GWP2088
R407C : GWP1774
R290 : GWP3
Focus of this presentation
R410A :
GWP2088
R410A : GWP2088
R134a : GWP1430
Cooling and Heating capacities range from <1 kW to > 10,000 kW

3. Revised F gas regulation :
GWP limits for air conditioners & heat pumps
No GWP limit for charges > 3kg
No GWP limit for multi split or VRF
All HFCs used in the equipment will be subject to the HFC “phase down”,
even if there is no specific ban or GWP limit.
“No GWP limit” is NOT equal to “business as usual” !
Ban on
HFC with
GWP 150
from 2020
For SINGLE split air conditioners with a charge BELOW 3 kg :
Ban on HFC with GWP 750 from 2025
No GWP limit for
Chillers
(unless Chiller is used for
refrigeration applications
where GWP 2500 is not
allowed)

4. Revised F gas regulation :
HFC “phase down” targets
In CO2equivalent HFC PHASE DOWN
TARGETS
Baseline Avg. 2009-2012
2015 100%
2016-2017 93%
2018-2020 63%
2021-2023 45%
2024-2026 31%
2027-2029 24%
2030 21%
Nearly 80%
reduction !
Reduction on the placing on EU market of HFCs – in CO2 equivalent = quantity x GWP
4

5. How to achieve this HFC phase down ?
Where possible :
1) Change to HFC refrigerants with a lower GWP
2) Change to non-HFC refrigerants
3) Reduce the HFC refrigerant quantity
4) Recover and reuse HFCs
5) Any combination of 1) 3) 4)
5

6. 6

7. Europe
7
First European models introduced
by Daikin since Autumn 2013

8. What is R32 ?
• R32= CH2F2 = difluoromethane = single substance (no blend)
• R410A = blend of 50% R32 + 50% R125
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9. GWP comparison of R410A & R32
Quantity GWP x Quantity
> 75% Reduction
• The GWP of
R32 is only
1/3rd of R410A
• Taking into
account the
refrigerant
charge, the
GWP is only
1/4th !
GWP Values according to IPCC 4th Assessment Report
For the EU F gas regulation the GWP values of IPCC 3rd report are valid
(R410A = 1975, R32 = 650)
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10. Impact of changing R410A  R32
in CO2equivalent
Tonne CO2 equivalent = kg of charge x GWP / 1000
1 kg of R410A
= 2.088 TCO2eq
= > 2 TCO2eq
R410A R32
1 kg of R32
= 0.675 TCO2eq
 For same kg of charge,
the TCO2eq of R32 is
3 times lower compared to
R410A
R32
0.7 kg of R32
= 0.4725 TCO2eq
 With lower kg of charge,
the TCO2eq of R32 can be
further reduced, up to 4
times lower compared to
R410A (depends on model design)
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11. Technically, installation of R32 unit is the same as R410A
Tools are slightly different
Tooling R410A R32
Manifold Normal Different
Scale Normal Normal
Vacuum pump Normal Normal
Leak detector Normal Different
Recovery unit Normal Different
Ventilation Recommended Necessary
Impact on installation / service
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12. Because R32 is a single component refrigerant (no blend) :
1. It is easier to handle
› can be charged in both gas and liquid phase
› no need to worry about composition change
after leakage
2. It is easier to recycle and reuse.
Impact on installation / service
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13. Some important design aspects of using R32:
Refrigerant properties
Compressor performance
Selection of oils
System dimensions
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14. Properties of R32
• Potential theoretical capacity :1.6 times larger compared to R410A
• Lower pressure loss : for same capacity , smaller piping diameter is possible
• Higher coefficient of heat transfer compared to R410A
• Charge volume reduction
• Liquid density 90% of R410A
• Volume reduction → up to 30% reduction against R410A possible
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15. If R32 is mixed with R1234ze(E), the average heat transfer coefficient drops.
As this becomes more prominent at lower mass flow, seasonal energy
efficiency will be negatively affected further
1) Average condensing heat transfer coefficient 2) Average evaporating heat transfer coefficient
R32-R1234ze(E) blend [R32 mass%] R32-R1234ze(E) blend [R32 mass%]
Source:Akio Miyara et.al. Proeedings from 46th The society of Heating, Air-Conditioning Sanitary Engineers of Japan (2012)
Impact of blending
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16. Charge
△20%
R410A R32
Unit size
Amount of Ref. 1250ｇ 1000ｇ
Class 1.0HP(2.2-.5kW/8500Btu) 1.0HP(2.2-2.5kW/8500Btu)
H693×W795×D300
795
H599×W718×D315
718
Volume
△18%
Case of Japan sales model (Nov.2012 on sale )
6%
R410A R32
Unit size
APF(Energy
efficiency)
6.6 7.0
Class 1.7HP(4.0kW/13,600Btu) 1.7HP(4.0kW 13,600Btu)
H693×W795×D300
795
Same
Size
Down
Sized
High
Energy
Efficiency
H693×W795×D300
795
APF:6.6 APF:6.6
System dimensions
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17. • R32 compressor discharge temperature is generally higher than
R32/HFO blends, however it is not an issue in most conditions, even in
high ambient cooling condition.
• In very low ambient heating condition, discharge temperature may need
to be controlled, e.g. by wet suction control.
40
60
80
100
120
140
160
180
200
220
0.8 0.85 0.9 0.95 1
X.suc [-]
DischargeTemp.[deg]
Te = -20 [deg]
－ 40
Tc [deg]
◆
▲
50
45
Comp. Efficiency [%]
50
60
－ 40
40
60
80
100
120
140
160
180
200
220
0.8 0.85 0.9 0.95 1
X.suc [-]
DischargeTemp.[deg]
Te = -30 [deg]
Tc [deg]
◆
▲
－
50
45
40
Comp. Efficiency [%]
50
60
Impact of wet suction control on R32 discharge temperatures
Compressor discharge temperature
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18. • POE or PVE oils currently used for R410A have poor
miscibility with R32
• New POE or PVE oils have good miscibility with
R410A and R32.
Selection of oils

19. 19
Source: the presentation of JX Nippon Oil & Energy Corporation (June 25, 2013)
New POE oils are available now which are excellent
for both R32 and R410A.

20. Source: the presentation of JX Nippon Oil & Energy Corporation (June 25, 2013)

21. Flammability classification of R32 = 2L
Class 1 Class 2L Class 2 Class 3
Not flammable Slightly
flammable
burning velocity
≤10 cm/s
Low flammable Highly
flammable
R744 (CO2) R1234yf / ze R152a R290
R410A R32
R717
(Ammonia)
Flammability of 2L refrigerants is very low.
The burning velocity (≤ 10 cm/s) is too slow to cause horizontal
flame propagation or explosion.
Classification according to ASHRAE34 & ISO817.
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22. R32
There is no “one-size-fits all” refrigerant
• Each manufacturer needs to make choices depending on the application and
the needs of the market & taking into account local legislations & standards.
• Daikin is developing R32 split air –conditioners from residential to commercial
range because R32 is suitable for these applications
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23. Is there a future for R32 in Europe ? Yes
Do we still need R410A in Europe ? Yes
• R32 fits in the EU “phase down” strategy to reduce F gas emissions
• R410A will still be needed for those applications where the use of
flammable refrigerants is restricted.
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24. R32 has excellent energy performance characteristics
in air conditioners and heat pumps.
R32 allows for reduced refrigerant charge and system
dimensions while maintaining or increasing energy
efficiency.
The higher discharge temperature of R32 is manageable
Suitable oils for R32 are available
R32 has the advantage of being a single component
refrigerant
Conclusions

25. Thank you !

26. GWP values
Refrigerant GWP current
F gas
regulation
Based on
3rd Assessment
report of IPCC
GWP new
F gas
regulation
Based on
4th Assessment
report of IPCC
HFC R32 550 675
R125 3400 3500
R134a 1300 1430
R143a 4300 4470
R404A (Blend of 44% R-125 + 52% R143a + 4%
134a)
3784 3922
R410A (Blend of 50% R32 + 50% R125) 1975 2088
HFO
(unsaturated
HFC)
R1234yf - 4
R1234ze - 7
Non HFC R744 (CO2) 1 1
R290 (propane) - 3
„Global Warming Potential‟ means the climatic warming potential of a fluorinated greenhouse gas relative to
that of carbon dioxide. The global warming potential (GWP) is calculated in terms of the 100-year warming
potential of one kilogram of a gas relative to one kilogram of CO2
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