摘要:
A transcritical refrigeration system includes a compressor, a gas cooler, an expansion device, and an evaporator. Refrigerant is circulated though the closed circuit system. Preferably, carbon dioxide is used as the refrigerant. A variable speed drive controls the speed of the refrigerant flowing through the compressor. Varying the speed of the refrigerant flowing through the compressor changes the mass flow rate of the refrigerant in the system to optimize the coefficient of performance.
摘要:
Refrigerant is circulated through a vapor compression system including a compressor, a gas cooler, an expansion device, and an evaporator. An auxiliary electric heater is activated to further heat the heated water exiting the gas cooler when the heating capacity of the system is low. The auxiliary electric heater can be located on the water line exiting the gas cooler, in a water tank that stores the heated water, or on the refrigerant line proximate to the compressor discharge.
摘要:
Refrigerant is circulated through a vapor compression system including a compressor, a gas cooler, an expansion device, and an evaporator. An auxiliary electric heater is activated to further heat the heated water exiting the gas cooler when the heating capacity of the system is low. The auxiliary electric heater can be located on the water line exiting the gas cooler, in a water tank that stores the heated water, or on the refrigerant line proximate to the compressor discharge.
摘要:
A refrigeration system includes a compressor, a gas cooler, an expansion device, and an evaporator. Refrigerant is circulated though the closed circuit system. Preferably, carbon dioxide is used as the refrigerant. As carbon dioxide has a low critical point, systems utilizing carbon dioxide as a refrigerant usually require the refrigeration system to run transcritical. When the system is operating inefficiently, the system is modified so the system operates efficiently. First, a parameter of the system is monitored by a sensor and the then compared to a stored value to determine if the system is operating inefficiently. If the system is operating inefficiently, the system is modified to an efficient system.
摘要:
A method of detecting and diagnosing operating conditions for a heat pump water heating system includes the steps of monitoring system operating conditions and comparing actual operating conditions to predicted operating conditions. The predicted operating conditions are based on expected pressures and temperatures given current system inputs. A difference between the actual and expected values for refrigerant pressures and temperature outside a desired range provides indication of a fault in the system. The system controller initiates a prompt to alert of the need for maintenance and direct to potential causes.
摘要:
A method of detecting and diagnosing operating conditions for a heat pump water heating system includes the steps of monitoring system operating conditions and comparing actual operating conditions to predicted operating conditions. The predicted operating conditions are based on expected pressures and temperatures given current system inputs. A difference between the actual and expected values for refrigerant pressures and temperature outside a desired range provides indication of a fault in the system. The system controller initiates a prompt to alert of the need for maintenance and direct to potential causes.
摘要:
A transcritical refrigeration system includes a compressor, a gas cooler, an expansion device, and an evaporator. Refrigerant is circulated though the closed circuit system. Preferably, carbon dioxide is used as the refrigerant. A fan moves outdoor air that exchanges heat with the refrigerant across the evaporator. The speed of the fan is regulated to regulate the evaporator pressure and to adapt the evaporator to different environmental conditions to achieve the optimal coefficient of performance. During high ambient conditions, the fan speed is decreased, decreasing the refrigerant mass flowrate in the system. The energy exchange per unit mass of the refrigerant in the gas cooler increases and the work of the fan decreases, increasing the coefficient of performance of the system. During low ambient conditions, the mass flowrate of the system is low and there is more heat transfer thermal resistance on the refrigerant side at the evaporator. The speed of the fan is lowered to decrease the work of the fan. Therefore, the coefficient of performance increases.
摘要:
A heat pump water heater system includes a compressor that has a variable clearance volume that can be selectively controlled to control the mass flow rate of refrigerant from the compressor. Under higher ambient air temperature conditions, the variable volume is increased to keep refrigerant in a variable clearance volume chamber and to decrease the mass flow rate of the refrigerant from the compressor. Under lower ambient air temperature conditions the variable volume is decreased to increase the mass flow rate. The variable clearance volume allows for maintaining optimum system performance under a variety of ambient air temperature conditions.
摘要:
A vapor compression system includes a compressor, a gas cooler, an expansion device, and an evaporator. Refrigerant is circulated through the system. The high side pressure of the vapor compression system is selected to optimize the heating capacity. In one example, the optimal high side pressure is obtained by determining the high side pressure that correlates to the maximum current required to operate to the water pump. In another example, the actual temperature of the water entering the gas cooler, the water exiting the gas cooler, and the ambient air temperature are measured and compared to a predetermined value to determine the optimal high side pressure.
摘要:
A heat pump water heater system includes a compressor that has a variable clearance volume that can be selectively controlled to control the mass flow rate of refrigerant from the compressor. Under higher ambient air temperature conditions, the variable volume is increased to keep refrigerant in a variable clearance volume chamber and to decrease the mass flow rate of the refrigerant from the compressor. Under lower ambient air temperature conditions the variable volume is decreased to increase the mass flow rate. The variable clearance volume allows for maintaining optimum system performance under a variety of ambient air temperature conditions.