Abstract: A burner pad for use in a gas burner in a gas fireplace includes a plurality of noncombustible fibers held together by fillers and binders to form a noncombustible body having an interior surface and an exterior surface. The body has a porosity that allows gas to pass therethrough in a substantially random manner. The body is also dimensionally stable. The burner pad may be used to form a gas burner having a burner pan having an open top with the porous burner pad enclosing the burner pan by covering said open top of said burner pan to define a gas distribution chamber between said pad and said burner pan. Gas is supplied to the gas distribution chamber and allowed to randomly seep through the pad where it may be ignited to form a low-profile, rolling flame that simulates the appearance of glowing embers in a wood-fueled fire.

Abstract: An S-shaped heat exchange tube with improved heat exchange efficiency. The tube is provided with a quartet of entry dimples in a first segment of the tube adjacent an inlet end of the tube, a first series of dimple pairs in a second segment of the tube and a second series of dimple pairs in a third segment of the tube.The quartet of entry dimples lie in a plane approximately perpendicular to a longitudinal axis of the first segment. At least the first three dimple pairs of the first series are graduated in depth, with the first dimple pair in the first series being provided adjacent to the first segment and having a depth less than a depth of the second dimple pair in the first series. The third dimple pair in the first series and all dimple pairs following the third dimple pair in the first series have depths which are equal. Depths of all dimple pairs in the second series are equal to the depth of the final dimple pair of the first series.