Bottled Water Cooler

Overview

A bottled water cooler dispenses chilled and near-boiling water from a single inverted bottle perched on top. Water leaves the bottle only as fast as it is drawn, because air has to bubble back up past the seal to replace it, the same trick that keeps an upside-down bottle from gushing. Inside, the supply splits into two independently conditioned tanks: one refrigerated, one heated.

The bottle seats on the Bottle & Reservoir, whose no-spill probe pierces the cap and feeds a small reservoir. From there gravity fills the Cold-Tank Refrigeration cold tank and the Hot Tank through separate tubes, with a baffle keeping the two thermal zones from mixing. The user draws water at the Dispensing Taps & Valves taps on the front, and a removable Drip Tray catches spills. All of it hangs inside a sheet-metal Cabinet.

Two systems run in parallel and never share a heat path, so one side can chill while the other holds near boiling.

How it works

The cold side is a miniature refrigerator. The Hermetic Compressor circulates R134a; the gas sheds heat in the Condenser Coil, a capillary tube drops its pressure, and the refrigerant then boils in evaporator tubing wrapped around the stainless cold tank, pulling the stored water down to a few degrees. A thermostat on the control board cycles the compressor to hold that temperature.

The hot side is simpler. A Heating Element inside the insulated hot tank brings its contents to roughly 90 °C, held by a Hot Tank Thermostat; an immersion Thermal Fuse cuts power permanently if the tank ever boils dry and overheats. The hot tap carries a child-lock so it cannot be opened accidentally.

The Control Board board ties both loops together, switching the compressor and the heater through separate relays based on two tank thermistors, and lighting cold and hot indicators. Because each tank only refills as water is dispensed, the cooler holds its two temperatures with very little standby energy between draws.