Monitoring of a Solar Combisystem Prototype

Abstract: This project work has been achieved in the Technical University of Denmark in the department of civil engineering. The project is carried out within the REBUS project (see ref. 15) that is researching on solar heating systems for combined space heating demand and hot water supply. In this case the prototype system is a solar combisystem with natural gas boiler.To ensure that the solar heating system object to study is working properly and it is able to guarantee the consumption of domestic hot water is a dwelling house and the required space heating, it is fundamental to have under control some basic parameters in the system. For this reason the monitoring of the system is essential and it is realized by placing in the correct place some sensors that give information about the temperatures of water flowing in the hydraulic circuit as well as the volume of water that is going through the pipes.To check all those parameters in the prototype system, several temperature sensors are installed in the hydraulic circuit, and also four flow meters that are going to measure the volume flow of water in the collector loop, DHW loop, space heating loop and boiler loop. To achieve the highest accuracy these devices have to be calibrated before being installed in the system. When the calibration of the flow meters and the temperature sensors is done and all the elements installed in the system, the measurement equipment is connected to a data logger that is programmed to receive and save all the data. The program designed for the data logger also calculates the amount of energy that is transferred in each one of the different loops in the system.At the end, the monitoring equipment is checked to prove that is is working properly and several tests charging and discharging the storage tank through different loops are performed to get an energy balance of each one of the processes. Not less important is to have under control other parameters as the temperature in the technical unit, where the natural gas boiler is placed and the humidity in the chimney of the natural gas boiler are going to be measured as well as the position of the different valves in the system to know in which direction the water is flowing through the different pipes.