| 摘要 |
A refrigeration system 4 (e.g. for a supermarket) sinks heat to a geothermal heat exchanger 38 and/or an ambient air heat exchanger 22, with a controller 53 regulating a fan 26 speed, geothermal fluid modulating valve 37 and a valve system 52,54,56 to selectively interconnect the heat exchangers in series or singularly. In a normal operation mode (II, fig 2) refrigerant passes through air exchanger 22 before the geothermal exchanger 38, with the fan at maximum speed. The lower the geothermal fluid temperature the higher its flow is controlled, and at full flow (mode III, fig 2) the fan speed may be decreased. The valve system can route refrigerant just or first to geothermal exchanger 38 based on temperature calculations (mode IV, fig 2) to give a good coefficient of performance. In a fault mode the valve system routes refrigerant just to air exchanger 22. Geothermal heat can be used in an HVAC system. |
