Abstract: Apparatus for use in controlling the temperature of the water in a kitchen sink (including a bathtub and/or other type of sink) for a reasonably extended period of time, without the necessity of adding additional hot water to the basin of the sink itself, to offset the loss of heat in the water as it naturally cools down over time. The invention also applies to the ability to maintain the water in a sink at a cool temperature, as opposed to a warm temperature. The preferred form of the invention provides a temperature controlling apparatus for a kitchen sink that can be integrally incorporated into the design of newly manufactured sink(s), and when activated by the user, automatically maintains the temperature of the water in the basin of a sink at an temperature level determined by the user.