Roof-mounted water heater

A hot liquid heater system at an area of a roof or outside wall of a building, the hot liquid heater system comprising:

• a heating chamber in which liquid is heated by solar energy from the sun, the heating chamber located proximate the roof or outside wall of the building;
• a first vacuum insulating glass (VIG) unit located above the heating chamber so that the solar energy passes through the first VIG unit before reaching the heating chamber;
• wherein the first VIG unit comprises first and second substantially parallel flat spaced apart glass substrates defining a gap therebetween, an edge seal provided around a periphery of the first and second glass substrates to form an hermetic seal, and a plurality of spacers provided between at least the first and second substrates, and wherein the gap between the first and second substrates is at pressure less than atmospheric pressure;
• a mounting structure formed from a non-glass material, the mounting structure having a length dimension and/or a width dimension that substantially match(es) the corresponding dimension(s) of the first VIG unit, the mounting structure being in direct physical contact with an outermost surface of the roof or outside wall of the building along said length and/or width dimension(s) such that the hot liquid heater system protrudes from the roof or outside wall of the building;
• a pair of sidewalls defining outer edges of the hot liquid hearing system and to which the first VIG unit and the mounting structure are attached;
• wherein the mounting structure is provided between the roof or outside wall of the building and the heating chamber;
• wherein the heating chamber is at least partially defined as being between the first VIG unit, the sidewalls, and the mounting structure;
• a second VIG unit located under the heating chamber and over the mounting structure so that the heating chamber is located between the first and second VIG units;
• and wherein the second VIG unit comprises third and fourth substantially parallel flat spaced apart glass substrates with a gap therebetween, an edge seal provided around a periphery of the third and fourth glass substrates to form an hermetic seal, and a plurality of spacers provided between at least the third and fourth substrates and wherein the gap between the third and fourth substrates is at pressure less than atmospheric pressure.