Solar heating panel unit and system therefor

A solar heating panel unit comprising first and second sides connected together along an at least substantially endless path to form a pouch having an internal chamber adapted to accommodate a heat transfer fluid, at least one opening being provided through said first and second sides in a position spaced from said chamber to provide for the mounting of said pouch and access means coupled to at least one of said sides for the supply and removal of said fluid to and from said chamber, said first side including a layer of black polyester, said second side including a lamination of reflective foil and plastic, said foil facing said chamber, said access means including inlet and outlet fixtures coupled to said pouch and including engaged members comprising flanges sandwiching one of said sides therebetween, said members defining a bore communicating with said chamber, one of said members extending into said chamber and including therein a cylindrical part spacing said sides apart and provided with radial openings connecting said bore with said chamber, said panel unit further comprising connecting means in said chamber connecting said first and second sides in offset parallel lines to define a serpentine path in the chamber for the flow of said fluid and also connecting said sides in transverse lines proximate said access means to form sub-chambers communicating with said serpentine path to divert the flow of fluid between said access means and said serpentine path.