Monitoring System of a Heat Pump Installation for Heating a Rural House Using Low-grade Heat from a Surface Watercourse

Increasing the efficiency of heat pump systems primarily used for heat supply to buildings is an important topic. This is especially true for systems constructed according to non-standard schemes and which use low-grade heat from various sources that are rarely considered for these purposes. Such studies require special, often expensive, data acquisition systems. In this paper, a low-cost computer-based monitoring system is presented. The monitoring system incorporates solutions which are new or seldom used. It is shown that modern semiconductor thermistors can replace commonly used platinum temperature sensors and thermocouples. A proposal for processing frequency output signals from sensors through an analog-to-digital converter and a way to reduce the number of required input channels are described. The monitoring system allows optimization of various types of heat-pump-based installations. The system has been used for quite a long time to monitor the operation of the heat pump installation using low-grade heat from a surface watercourse. With its help, the feasibility of using the previously proposed submersible floating heat exchanger is justified and the optimal scheme for its placement in the watercourse is determined.