Abstract: A solar collector venting system comprising a lower frame member with vents which allow the entrance of cooling air when high collector stagnation temperatures occur communicating with the natural downward thermal bowing of a two walled plastic glazing caused by differences in coefficients of expansion between the cooler upper layer and the hotter inner layer of plastic glazing communicating with an upper frame member with stationary fulcrum points communicating with vents in between the fulcrums points which, upon bowing of the glazing cause the upper end of the glazing sheet to lift up off the top frame member allowing an open path for the flow of cooling air to pass up thru the collector between the absorber and the plastic glazing whose path may be kept clear by communicating with flow path spacers on the absorber.

Abstract: A solar water heating system comprising a solar energy collector which comprises a solar energy absorber communicating with a fluid distribution manifold, a drainback tank communicating with the distribution manifold for collecting drainage fluid from the distribution manifold, a pump activated by a differential controller, and a heat exchanger within a water storage tank. The distribution manifold comprises a floating valve header which seals the manifold during fluid feed and allows air to pass during non-active periods.