This heating system heats a heat medium flow path of a solar thermal collector (8). This heat medium flow path comprises, connected in series, a heat collector tube, a flexible hose, and piping. Eachof these has different electrical resistance. This heating system is provided with an electrification unit (67) which electrifies the heat medium flow path in order to heat the heat medium flow path,a temperature measurement unit (66) which measures the temperature of the piping, and a processing unit (75) which compares the measured temperature of the piping with a preset piping temperature expected given the length of electrification, and performs processing depending on the comparison result.