water and until the closed loop is filled with the heat transfer fluid.
Exposing a “dry” collector to the solar radiation will cause the absorber to
develop high temperatures (more than 150
o
C). Under these conditions, there
is the possibility of boiling of the heat transfer fluid (when it will be put in the
collector) and as a consequence the danger of an accident. In addition, the
connecting ends of the collector will develop high temperature.
2. Solar collector 27. Lower collector support bar
Figure 4.7a Fastening the collector on the mounting frame (Step 1).
27
27
2