Air Conditioners Move Heat
All scenes › Chapter 4 Outdoor unit: dump the heat
Dumping heat outdoors
Hot refrigerant hands its heat to the outdoor air
View in 3DHot refrigerant, cooler outdoors
Hot refrigerant gas at about 92 °C enters the winding pipes inside the outdoor unit (the condenser). The outdoor unit’s fan draws 35 °C outdoor air between the pipes and blows it out the front. The refrigerant is hotter than the air, so this time heat passes from the refrigerant to the air. That is why the air blowing from an outdoor unit is hot.
Why?It is the same rule: heat flows from the hot side (the refrigerant) to the cold side (the outdoor air). This flow only happens because the compressor made the refrigerant hotter than the outdoors.
Learn moreIf an outdoor unit is boxed in, the hot air it blows out cannot escape and gets sucked back in, so it cannot dump heat well. That is why the space in front of and behind an outdoor unit should be kept clear.
- Refrigerant in the outdoor unit’s pipes
- 92 → 45 °C
calculated from R-32 property tables (CoolProp) · example: room 27 °C, outdoors 35 °C
View this scene in 3D →Read more
Wikipedia: Condenser (heat transfer)
More in the series
Temperatures, pressures and amounts of heat are calculated from property tables for the refrigerant R-32 (CoolProp). The example is a home air conditioner removing 2.5 kW of heat, with the room at 27 °C and the outdoors at 35 °C. In the 3D view, the refrigerant moves far slower than in real life, and the inside of the compressor and the expansion valve are shown as enlarged, simplified models.