System Drop-In Test of R-410A Alternative Refrigerant R-32 in a Water-to-Air Heat Pump

Transcription

1 e System Drop-In Test of R-410A Alternative Refrigerant R-32 in a Water-to-Air Heat Pump Phillip A. Johnson, Daikin Applied 2016-Jan Daikin Applied People and ideas you can trust. TM

2 Acknowledgements Daikin Applied, Applied Terminal Systems (Auburn, NY) Benny DiMarco John McLaughlin 2016 Daikin Applied Page 2

3 Refrigerants Tested Equipment Type Refrigerant IPCC AR4 (2007) GWP 100 IPCC AR5 (2014) Composition R-32 R-125 Water-source heat pump (water-loop application) R-410A % 50% R % 0% baseline 2016 Daikin Applied Page 3

4 Equipment Description Water-source heat pump (liquid to air) Water-loop application Two-stage capacity Full Load Part Load Btu/h W Btu/h W Vertical, Floor Mount Integral fan (EC motor), external pump Thermal expansion valve (non-adjustable) Heat exchanger type & materials Air-Refrigerant RTPF Cu tube Al fin Water-Refrigerant Co-Axial Cu tube Steel tube 2016 Daikin Applied Page 4

5 Test Method System Drop-In Test Capacity and efficiency measured per ISO :1998 ASHRAE Standard Facility R-410A Daikin Applied, Minneapolis, MN R-32 Intertek, Cortland, NY not ideal for comparison testing Lab schedule and other logistics prevented using the same facility for both tests Daikin Applied Page 5

6 Test Method Charge quantity R-410A R-32 Lubricant factory standard (optimized for cooling full load efficiency) same by mass (non-optimized) not a fair comparison POE oil, ISO viscosity grade 32 (no change to type or quantity) TXV setup to control compressor suction superheat non-adjustable TXV (factory preset) R-410A factory standard TXV, no change for R-32 drop-in test TXV re-selection would be a soft-optimization test type Lost time due to facility logistics. Due to schedule delay, charge optimization not conducted for alternate refrigerant Daikin Applied Page 6

7 Test Method Rating and Test Target Conditions Water-Loop Heat Pump, per ISO :1998 Water inlet 86.0 F 30.0 C 68.0 F 20.0 C dry bulb temperature 80.6 F 27.0 C 68.0 F 20.0 C Air wet bulb temperature 66.2 F 19.0 C 59.0 F 15.0 C (Indoor) inlet relative humidity ( 47 %rh ) ( 59 %rh ) (for reference only) Efficiency Ratings with R-410A Full Load Part Load EER COP EER COP 2016 Daikin Applied Page 7

8 Results Efficiency decreased significantly, due to using same refrigerant charge quantity for R-32, and not changing the TXV Liquid sub-cooling increased significantly Unit was significantly over-charged! R-32 results relative to baseline test with R-410A Capacity Efficiency Subcooling at TXV Inlet Full Load 99.9% 106.5% Part Load 100.6% 101.0% Full Load 86.4% 94.1% Part Load 92.2% 96.9% Full Load +8Δ F [+4Δ C] +15Δ F [+8Δ C] Part Load +5Δ F [+2Δ C] +8Δ F [+4Δ C] 2016 Daikin Applied Page 8

9 Results Additional items Compressor Discharge Temperature R-410A Full Load F [59.3 C] F [55.4 C] Part Load F [55.0 C] F [55.4 C] R-32 Full Load F [80.9 C] F [81.0 C] Part Load F [72.0 C] F [70.4 C] Results relative to baseline test with R-410A Cooling Heating Full Load +38.9Δ F [+21.6Δ C] +46.1Δ F [+25.6Δ C] Part Load +30.6Δ F [+17.0Δ C] +27.0Δ F [+15.0Δ C] 2016 Daikin Applied Page 9

10 Results Additional items Superheat at Compressor Suction Results relative to baseline test with R-410A Cooling Heating Full Load +3.7Δ F [+2.0Δ C] +3.3Δ F [+1.8Δ C] Part Load +4.9Δ F [+2.7Δ C] +6.1Δ F [+3.4Δ C] Superheat at Compressor Discharge Results relative to baseline test with R-410A Cooling Heating Full Load +35.3Δ F [+19.6Δ C] +42.7Δ F [+23.7Δ C] Part Load +28.3Δ F [+15.7Δ C] +28.3Δ F [+15.7Δ C] 2016 Daikin Applied Page 10

11 Conclusions Lessons Learned For drop-in testing, adjust expansion device (when adjustable) and perform charge optimization for both baseline and candidate using the same target metric. For lowest uncertainty in comparison testing, with relative results, use the same test facility for both baseline and candidate tests 2016 Daikin Applied Page 11

12 e Questions? 2014 Daikin Applied People and ideas you can trust. TM

13 e Thank You! 2014 Daikin Applied People and ideas you can trust. TM