An Experimental Study of the Effect a Ground-Source Heat Pump with a Soil Temperature Potential Recovery System Has on the Soil Thermal Imbalance under Cold Climate Conditions

Abstract

Ground thermal balance disturbance is a serious problem that arises during the operation of heat pumps with a geothermal circuit. In regions with cold climate and high space heating loads, ground freezing leads to a significantly degraded performance of heat pumps during their long-term operation. Experimental studies to estimate the effect the ground temperature potential recovery system operation has on the ground thermal imbalance under the climatic conditions of the city of Moscow were conducted. The system considered includes three fan coils, which operate for air conditioning of building rooms. The excess heat extracted from air is transferred through a storage tank to the geothermal circuit wells. The system has shown its good performance, because with a longer time of heat pump operation with commensurable load, an insignificant decrease in the average ground temperature and in the heat carrier temperature at the heat pump evaporator inlet were noted. The use of such systems will help increase the effective service life of heat pumps with a geothermal circuit and expand their possible application field to colder regions with a strongly pronounced imbalance of thermal loads.