# US 8,539,783 B1 · System for preventing condensation on refrigerator doors and frames > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,539,783 B1 - Document ID: US8539783B1 - Status: Granted - Kind: B1 - Application number: 12/710,285 - Filed: 2010-02-22 - Granted: 2013-09-24 - Earliest claimed: 2004-02-11 - Assignees: Supermarket Energy Technologies, LLC - Applicants: John Bunch - Inventors: John Bunch - Web page: https://patentgrep.com/patent/US8539783B1 ## CPC - A47F 3/0482: {Details common to both closed and open types} - F25D 21/04: Preventing the formation of frost or condensate - F25B 2600/07: Remote controls - F25D 21/02: Detecting the presence of frost or condensate - A47F: SPECIAL FURNITURE, FITTINGS, OR ACCESSORIES FOR SHOPS, STOREHOUSES, BARS, RESTAURANTS OR THE LIKE; PAYING COUNTERS - F25D: REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR (refrigerated showcases A47F3/04; thermally-insulated vessels for domestic use A47J41/00; refrigerated vehicles, see the appropriate subclasses of classes B60 - B64; containers with thermal insulation in general B65D81/38; heat-transfer, heat-exchange or heat-storage materials, e.g. refrigerants, or materials for the production of heat or cold by chemical reactions other than by combustion C09K5/00; thermally-insulated vessels for liquefied or solidified gases F17C; air-conditioning or air-humidification F24F; refrigeration machines, plants, or systems F25B; cooling of instruments or comparable apparatus without refrigeration G12B) - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS ## Abstract An improved refrigerator energy management system removes condensation from glass refrigerator doors in an energy efficient manner by operating refrigerator frame heaters independently of refrigerator door heaters. Sensors for detecting humidity or condensation transmit data to a control unit that controls electrical current supplied to separate door and frame heater wires. Additional sensors for controlling the refrigerator lighting and monitoring the power consumption of refrigerator fans may transmit data to the control unit. A command unit may receive data from multiple control units, compile the data, and make it available over the internet to a shopkeeper monitoring the system from a remote location. The sensors, control unit, and command unit all communicate on a wireless peer-to-peer network using the ZigBee protocol. ## Claims ### Claim 1 A system for controlling energy usage in a refrigerator having: a) a frame; b) a frame heater attached to the frame; c) a door attached to the frame; and d) a door heater attached to the door; the system comprising a control unit connected to the frame heater and the door heater and configured to activate and deactivate the frame heater independently of activating and deactivating the door heater, wherein the control unit is configured to activate and deactivate the frame heater asynchronously from activating and deactivating the door heater. ### Claim 2 (depends on 1) The system of claim 1 wherein the control unit comprises: a) a housing; b) a coupling mounted on the housing, the coupling electrically connecting the control unit to a power source by a main power wire, to the frame heater by a frame heater wire, and to the door heater by a door heater wire; c) a computer processor in electrical communication with the coupling; and d) at least one transceiver in electrical communication with the computer processor. ### Claim 3 (depends on 2) The system of claim 2 further comprising a first anti-sweat sensor attached to the door and configured to send data regarding humidity near the door to the computer processor via the transceiver. ### Claim 4 (depends on 3) The system of claim 3 wherein the data regarding humidity comprises the humidity level, and wherein the computer processor is programmed to activate the door heater if the humidity level exceeds a predetermined threshold. ### Claim 5 (depends on 3) The system of claim 3 wherein the data regarding humidity comprises an input signal that is generated when the first anti-sweat sensor detects humidity that exceeds a predetermined threshold, and wherein the computer processor is programmed to activate the door heater if the input signal is received. ### Claim 6 (depends on 3) The system of claim 3 further comprising a second anti-sweat sensor attached to the frame and configured to send data regarding humidity near the frame to the control unit. ### Claim 7 (depends on 2) The system of claim 2 wherein the refrigerator further comprises at least one fan having a fan motor, the system further comprising a fan power sensor configured to detect the amperage of the fan motor and transmit data comprising the amperage to the computer processor. ### Claim 8 (depends on 7) The system of claim 7 wherein the computer processor is programmed to: a) compare the amperage to a predetermined threshold to determine if the fan motor is working properly; and b) send an alert signal to a computer in communication with the transceiver if the comparison indicates that there is a problem with the fan motor. ### Claim 9 (depends on 7) The system of claim 7 wherein the refrigerator comprises a floor with a drain therein, the system further comprising a water level sensor positioned near the drain and configured to alert the computer processor if the water level sensor becomes submerged in water. ### Claim 10 (depends on 2) The system of claim 2 wherein the coupling electrically connects the control unit to one or more lights by a lighting control wire, and wherein the computer processor is configured to control the lights. ### Claim 11 (depends on 10) The system of claim 10 further comprising a motion sensor positioned outside the refrigerator and configured to notify the computer processor when motion is detected, wherein controlling the lights comprises supplying or denying an electrical current to the lighting control wire based on the time of day and whether motion is detected. ### Claim 12 (depends on 11) The system of claim 11 wherein placing the lights in a “dim” state comprises pulsing a current supplied to the lighting control wire. ### Claim 13 (depends on 2) The system of claim 2 further comprising a command unit in communication with the control unit, the command unit comprising: a) a microprocessor; b) an access controller that is connected to the internet; and c) a command transceiver that sends and receives data between one or more of the transceivers in the control unit. ### Claim 14 (depends on 13) The system of claim 13 wherein the computer processor may be programmed by inputting parameters over the internet, the parameters being transmitted to the command unit and subsequently to the computer processor. ### Claim 15 (depends on 13) The system of claim 13 wherein the command transceiver and the transceiver in the control unit with which the command transceiver communicates are wireless transceivers. ### Claim 16 (depends on 15) The system of claim 15 wherein the command unit and control unit communicate on a wireless network compliant to the IEEE 802.15.4 standard. ### Claim 17 (depends on 1) The system of claim 1 wherein the computer processor is programmed to: a) activate the door heater at a first predetermined time for a first predetermined duration; and b) activate the frame heater at a second predetermined time for a second predetermined duration. ### Claim 18 (depends on 17) The system of claim 17 wherein the computer processor is programmed to: a) receive input from one or more anti-sweat sensors; and b) override activation of the door heater at the first predetermined time based on the input.