During the last years, solar thermal systems have lost in attractiveness mostly due to their high initial installation costs, higher complexity compared to photovoltaic systems and a regular need of maintenance to avoid overheating and freezing problems, e.g. control of glycol mixture properties. Drainback (DB) solar thermal systems may overcome some of these issues and contribute to the market recovery as it prevents overheating and freezing of the solar system components even when pure water is used as the heat carrier fluid. It also needs less components than classical pressurised systems, which leads to less complex, lower system costs. Nevertheless, this type of system has not been very successful in Switzerland, only accounting for a small part of the market. In order to identify the barriers preventing the wide Swiss acceptance of DB systems, a literature review was performed and an online survey conducted and addressed to the different actors of the solar thermal sector. The aim is to understand the reasons of low market penetration of DB systems in Switzerland and to clearly identify the main barriers to its spreading. Results show that investments in research, product development, technology demonstration and market deployment in the form of professional training and technology information are essential to promote the DB in Switzerland.