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Ahlsell Danfoss (Danmark) IVT Thermia Värme Alfa Laval Dorin (Italy) NIBE Climacheck Green and Cool RANOTOR Climate well Güntner (Germany) SRM Per Lundqvist, Yang Chen, Energy Department, Royal Institute of Technology [email protected] / [email protected] The first CO2 heat pump for the Swedish market was released by Ahlsell on July 10 th , 2005 Capacity-controlled by a variable- speed control (inverter). An air source heat pump provides both space heating and domestic hot water (DHW) heating. It is claimed to deliver 4.5 kW heat power down to an outdoor air tempe- rature of -15 °C and to be able to heat the water up to +70 °C. tank charging with electric heater at -2°C Tamb - 2008-04-29 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 0 900 1800 2700 3600 4500 5400 6300 7200 8100 9000 9900 10800 11700 time [s] temperature [°C] 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Flow [m3/h]; power [kW]; COP [-] T_top T1 T2 T3 T4 T5 T6 water gas cooler out water gas cooler in deltaT_strat compr. power Flow scaled 10 [m3/h] COP el. heater stops tank charging with no electric heater at -2°C - 2008-05-01 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 0 900 1800 2700 3600 4500 5400 6300 7200 8100 9000 9900 10800 11700 time [s] temperature [°C] 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Flow [m3/h]; power [kW]; COP [-] T_top T1 T2 T3 T4 T5 T6 water gas co in water gas co out deltaT_strat compr. Powe flow scaled 1 [m3/h] COP Frosting-defrosting periods at -2 degreeC T amb and 3,4kW heating load 2008-04-14 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 0 1800 3600 5400 7200 9000 10800 12600 14400 16200 18000 19800 21600 23400 time[s] temperature [C] -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 heating capacity [kW]; flow [-]; COP [-]; power [kW] evap. air in evap. air out CO2 compr. In water gas cooler in water gas cooler out CO2 Exp.-valve in CO2 compr. Out Comp normalized flow [x/0,239] heating capacity COP problem in data logging defrosting periods temperature approach before defrosting 1st 2nd
