ASHP (air source heat pump) water heater is a renewable and energy efficient device used for sanitary hot water production. The system comprises of a storage tank and heat pump connected by pipes. These major units ...ASHP (air source heat pump) water heater is a renewable and energy efficient device used for sanitary hot water production. The system comprises of a storage tank and heat pump connected by pipes. These major units can either be compact as in the integrated model or split as in the retro-fit model. In this research, the analysis of energy losses was performed using SIRAC (the Southern African refrigeration and air conditioning) residential split type heat pump of 1.2 kW input power to retrofit a 200 liter high pressure kwikhot storage tank without hot water being drawn off for the entire monitoring period. Likewise to experimentally determine the losses DAS (data acquisition system) was designed and built to measure Ta (ambient temperature; RH-relative humidity), RH, To (ASHP outlet water temperature), Ti (ASHP inlet water temperature) and Vh. (volume of water heated by ASHP unit).The results showed that the heat energy gain to compensate standby losses could range from 1.8 kWh to 2.1 kWh with the corresponding electrical energy used by ASHP water heater ranging from 0.55 kWh to 0.66 kWh. The standby losses depend primarily on the Vh, the Ta and the RH while the influence of (To - Ti) is secondary. The results can be of valuable interest to manufacturer of retrofit ASHP unit for hot water production when matching the electrical energy required to compensate for the standby losses.展开更多
文摘ASHP (air source heat pump) water heater is a renewable and energy efficient device used for sanitary hot water production. The system comprises of a storage tank and heat pump connected by pipes. These major units can either be compact as in the integrated model or split as in the retro-fit model. In this research, the analysis of energy losses was performed using SIRAC (the Southern African refrigeration and air conditioning) residential split type heat pump of 1.2 kW input power to retrofit a 200 liter high pressure kwikhot storage tank without hot water being drawn off for the entire monitoring period. Likewise to experimentally determine the losses DAS (data acquisition system) was designed and built to measure Ta (ambient temperature; RH-relative humidity), RH, To (ASHP outlet water temperature), Ti (ASHP inlet water temperature) and Vh. (volume of water heated by ASHP unit).The results showed that the heat energy gain to compensate standby losses could range from 1.8 kWh to 2.1 kWh with the corresponding electrical energy used by ASHP water heater ranging from 0.55 kWh to 0.66 kWh. The standby losses depend primarily on the Vh, the Ta and the RH while the influence of (To - Ti) is secondary. The results can be of valuable interest to manufacturer of retrofit ASHP unit for hot water production when matching the electrical energy required to compensate for the standby losses.