Chromagen Solar Forced Circulation Systems CHROMAGEN Solar Forced Circulation Systems  (42 REC's) 302VOBP10G26 (300 L tank on ground, 2 x BP10 panels, 26L/min gas booster) Adjustable Roof stand for collectors   A pump and control unit are utilised to ensure correct water circulation. This allows the collectors to be situated away from the tank. For example, the tank may be situated in a basement while the collectors remain on the roof. Orig: $5,015.51 Sale: $4,315.00