An experimental solar heating system heats five modular classrooms at the Fauquier County High School in Warrenton, Virginia. The present report covers the operation, maintenance, and modifications to the system over the 1974-75 and 1975-76 heating seasons. The solar system has shown the capability of providing essentially 100 percent of the heating requirements of the five classrooms it serves. The drain-down method of freeze protection has functioned well with no damage to the system occurring as a result of freezing. The corrosion inhibitor has worked well with the aluminum absorber plates with no failures arising from internal corrosion. The selective coating appears to have degraded in terms of its solar absorptance and this has led to some loss in collector thermal performance. A control system has been developed and installed to allow the system to operate automatically in its most efficient mode. The rubber hose connections have failed repeatedly due to the high temperatures attained by the collector under no-flow conditions. Vandalism has been practically nonexistent in spite of the readily accessible location of the solar collector. Interest in the solar heating system has been high and the system has been viewed by a large number of visitors from the United States as well as throughout the world. (Author/MLF)