A solar collector, comprising a) a rectangular bottom, b) a frame, extending from an outer periphery of the bottom and perpendicular to said bottom, which frame comprises four wall sections (W1-W4) and four comer sections (E1-E4), c) an outer, rectangular glass pane, which is fastened to said frame at an upper end of said frame, which upper end being arranged opposite to said bottom, d) an inner, rectangular glass pane, which is fastened to said frame at a distance to the outer glass pane between outer glass pane and bottom, wherein e) said distance between inner and outer glass panes (16, 14) and thus a space between inner and outer glass panes (16,14) is defined by spacers, connecting said inner and outer glass panes (16, 14) at their respective peripheral areas (16R, 14R), f) an absorber sheet, arranged at a distance to said inner glass pane between said inner glass pane and said bottom, g) at least one riser arranged at distance to said bottom between said absorber sheet und said bottom, wherein h) said bottom, said frame and said outer glass pane define a box-shaped collector space, and i) the bottom, the outer glass pane, the inner glass pane, the absorber sheet and the risers extend predominantly parallel to each other, characterized in that the solar collector further comprises: j) at least two ventilation caps arranged at a distance to each other, and each cap comprising: j 1) a first section, abutting with an inner side against an outer side of the frame at the upper end of said frame, j2) a second section, extending orthogonally to the first section, overlapping with an inner side a terminal upper front face of the frame, wherein j3) the inner sides (32I, 34I) of both first and second sections (32, 34) each display a pattern (32P, 34P, 34Z), providing at least one continuous ventilation channel along said inner sides (32L, 34L), which ventilation channel leads from an outside into said collector space, and j4) said ventilation channel is fluidly connected via at least one opening. in said spacers to said space between the inner and outer glass panes (16, 14). a) a rectangular bottom, b) a frame, extending from an outer periphery of the bottom and perpendicular to said bottom, which frame comprises four wall sections (W1-W4) and four comer sections (E1-E4), c) an outer, rectangular glass pane, which is fastened to said frame at an upper end of said frame, which upper end being arranged opposite to said bottom, d) an inner, rectangular glass pane, which is fastened to said frame at a distance to the outer glass pane between outer glass pane and bottom, wherein e) said distance between inner and outer glass panes (16, 14) and thus a space between inner and outer glass panes (16,14) is defined by spacers, connecting said inner and outer glass panes (16, 14) at their respective peripheral areas (16R, 14R), f) an absorber sheet, arranged at a distance to said inner glass pane between said inner glass pane and said bottom, g) at least one riser arranged at distance to said bottom between said absorber sheet und said bottom, wherein h) said bottom, said frame and said outer glass pane define a box-shaped collector space, and i) the bottom, the outer glass pane, the inner glass pane, the absorber sheet and the risers extend predominantly parallel to each other, j) at least two ventilation caps arranged at a distance to each other, and each cap comprising: j 1) a first section, abutting with an inner side against an outer side of the frame at the upper end of said frame, j2) a second section, extending orthogonally to the first section, overlapping with an inner side a terminal upper front face of the frame, wherein j3) the inner sides (32I, 34I) of both first and second sections (32, 34) each display a pattern (32P, 34P, 34Z), providing at least one continuous ventilation channel along said inner sides (32L, 34L), which ventilation channel leads from an outside into said collector space, and j4) said ventilation channel is fluidly connected via at least one opening. in said spacers to said space between the inner and outer glass panes (16, 14). j 1) a first section, abutting with an inner side against an outer side of the frame at the upper end of said frame, j2) a second section, extending orthogonally to the first section, overlapping with an inner side a terminal upper front face of the frame, wherein j3) the inner sides (32I, 34I) of both first and second sections (32, 34) each display a pattern (32P, 34P, 34Z), providing at least one continuous ventilation channel along said inner sides (32L, 34L), which ventilation channel leads from an outside into said collector space, and j4) said ventilation channel is fluidly connected via at least one opening. in said spacers to said space between the inner and outer glass panes (16, 14).