This standard applies to non-tracking type solar collectors (hereinafter referred to as collectors) such as flat plate types and vacuum glass tube types that collect solar heat as sensible heat by forced circulation of liquid as a heat collection medium. Specifies the thermal performance test method. Applicable to heat collectors with a reflector and heat collectors with a working medium for heat transfer from the heat collector to the heat collecting medium, such as heat pipes, but also heat collectors without a transmitter and those with a heat storage function. Not applicable to heat collectors.