# US 9,752,798 B2 · Water heater control using external temperature sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,752,798 B2 - Document ID: US9752798B2 - Status: Granted - Kind: B2 - Application number: 15/050,548 - Filed: 2016-02-23 - Published: 2016-06-16 - Granted: 2017-09-05 - Earliest claimed: 2006-01-27 - Assignees: Emerson Electric Co. - Applicants: Emerson Electric Co. - Inventors: Thomas P. Buescher; Thomas J. Fredricks; Rishi Siravuri - Web page: https://patentgrep.com/patent/US9752798B2 ## CPC - F24H 9/2021: {Storage heaters} - F24H 9/25: of remote control devices or control-panels - F24H 15/144: Measuring or calculating energy consumption - F24H 15/156: Reducing the quantity of energy consumed; Increasing efficiency - F24H 15/164: where the price of the electric supply changes with time - F24H 15/174: Supplying heated water with desired temperature or desired range of temperature - F24H 15/225: at different heights of the tank - F24H 15/238: Flow rate - F24H 15/281: Input from user - F24H 15/315: of mixing valves - F24H 15/37: of electric heaters - F24H 15/395: Information to users, e.g. alarms - F24H 15/421: using pre-stored data - F24H 15/45: remotely accessible - G05D 23/1931: {to control the temperature of one space} - H05B 1/0297: {Heating of fluids for non specified applications} - F24D 2220/042: Temperature sensors - F24D 2240/26: Vertically distributed at fixed positions, e.g. multiple sensors distributed over the height of a tank, or a vertical inlet distribution pipe having a plurality of orifices - F24H 1/202: {with resistances} - F24H 15/12: Preventing or detecting fluid leakage - F24H 15/20: characterised by control inputs - F24H: FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL (steam generation F22) - G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - F24D: DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR (using steam or condensate extracted or exhausted from steam engine plants for heating purposes F01K17/02) ## Abstract A system and method for controlling a water heater that operates according to a voltage supply includes a temperature sensor, mounted on at least one of a temperature and pressure (T&P) valve of the water heater and a hot water line of the water heater, that generates a temperature signal corresponding to a first temperature of the at least one of the T&P valve and the hot water line. A control module mounted on the water heater includes a switching module that receives the voltage supply and outputs the voltage supply to the water heater. The voltage supply passes at least one of through and adjacent to the control module. The control module determines a second temperature of water within the water heater based on the temperature signal and selectively actuates the switching module to turn on and turn off the voltage supply to the water heater based on the second temperature. ## Claims ### Claim 1 A method for controlling a water heater that operates according to a voltage supply, the method comprising: mounting a temperature sensor on at least one of a temperature and pressure (T&P) valve of the water heater and a hot water line of the water heater; generating a temperature signal corresponding to a first temperature of the at least one of the T&P valve and the hot water line; mounting a control module on the water heater, the control module including a switching module that receives the voltage supply and outputs the voltage supply to the water heater, wherein the voltage supply passes at least one of through and adjacent to the control module; and using the control module, determining, using the first temperature indicated by the temperature signal, a second temperature, wherein the second temperature is an actual temperature of water within the water heater, and wherein the first temperature and the second temperature are different, and selectively actuating the switching module to turn on and turn off the voltage supply to the water heater based on the second temperature. ### Claim 2 (depends on 1) The method of claim 1 further comprising determining a relationship between the first temperature and the second temperature. ### Claim 3 (depends on 2) The method of claim 2 further comprising: monitoring the first temperature for a predetermined period; and determining the relationship based on changes in the first temperature during the predetermined period. ### Claim 4 (depends on 2) The method of claim 2 wherein the relationship includes an offset between the first temperature and the second temperature. ### Claim 5 (depends on 2) The method of claim 2 further comprising determining the relationship based on a maximum of the first temperature during a predetermined period. ### Claim 6 (depends on 5) The method of claim 5 wherein the maximum is related to a temperature setpoint of the water heater, and wherein when the first temperature is at the maximum, the second temperature is at the temperature setpoint. ### Claim 7 (depends on 6) The method of claim 6 further comprising determining the relationship based on a difference between the temperature setpoint and the maximum. ### Claim 8 (depends on 6) The method of claim 6 further comprising programming the control module with the temperature setpoint. ### Claim 9 (depends on 6) The method of claim 6 further comprising selecting the temperature setpoint from a plurality of possible temperature setpoints. ### Claim 10 (depends on 1) The method of claim 1 further comprising: determining usage history of the water heater based on the voltage supply; and selectively actuating the switching module further based on the usage history. ### Claim 11 (depends on 10) The method of claim 10 further comprising selectively actuating the switching module further based on at least one of peak usage information, load shedding information, and tiered pricing information. ### Claim 12 (depends on 10) The method of claim 10 further comprising selectively actuating the switching module further based on a predetermined minimum temperature. ### Claim 13 (depends on 12) The method of claim 12 wherein the predetermined minimum temperature is a predetermined amount less than a temperature setpoint of the water heater.