A solar collector housing that is opened and closed without tools includes structure for accommodating temperature-related expansion and contraction of a polymer absorber housed within the collector. The housing includes a transparent cover, a frame for holding the transparent cover, and a base. The cover, frame and base collectively define a hollow interior within which the polymer absorber is positioned. A plurality of latches is secured to an exterior of the frame. The frame and base are pivotally connected to one another when the latches are open so that the collector housing can be opened. The housing cannot be opened when the latches are closed. A pair of variable gate closure components are positioned in slots formed in a second end of the collector and enable the polymer absorber to expand and contract without placing stress on the absorber tubes.

Provided is an improved coupling for preventing water leakage in heating systems that include solar collector panels which incorporate plastic or rubber tubes that are connected to inlet and outlet water manifolds. The couplings are reinforced, dual durometer materials that are flexible enough to form a strong seal to any cylindrical tubes or pipes utilized in the heating system as well as rigid enough to tolerate the expansion and contraction of the coupling body during extreme conditions of use.

An arrangement for producing hot water from solar energy, the arrangement comprising: an elongate solar collector device extending along a longitudinal direction (X) from a first end to an opposite second end, the elongate solar collector device consisting of an elongate profile having walls that in between them define elongate cavities extending from the first end to the second end, the elongate solar collector device having at least one first opening for receiving water into the elongate cavities, and at least one second opening for tapping off water, arranged at a middle part of the elongate solar collector device; and at least one valve adapted to be arranged in a respective one of the at least one second opening, the valve being openable and closable in order to be able to tap off any water housed in the cavities.

A solar thermal collector adapted to be assembled from a flat pack configuration, comprising a conduit (6) configured to carry fluid and to absorb radiation, a base (1) above which the conduit (6) is mounted and a plurality of panels configured to interconnect with the base (1) to produce a housing (8) for the conduit (6).