Systems and methods for controlling a water heater

• US 9,103,550 B2
• Filed: 05/11/2012
• Issued: 08/11/2015
• Est. Priority Date: 02/07/2005
• Status: Active Grant

• Current Assignee: Copeland Comfort Control LP (Emerson Electric Company)
• Original Assignee: Emerson Electric Company
• Inventors: Arensmeier, Jeffrey N., Donnelly, Donald E., Evans, Edward B., Haefner, John S., Vogel, G. Scott
• Primary Examiner(s): Wilson, Gregory A
• Application Number:
  US13/469,723
• Publication Number:
  US 20120227682A1
• Time in Patent Office: 1,187 Days
• Field of Search: 122/13.01, 122/14.2, 122/14.31, 122/14.21, 122/504, 236/46.R
• US Class Current: 1/1
• CPC Class Codes: F23M 2900/11021 Means for avoiding accidental fires in rooms where the combustion device is located
• CPC Class Codes: F23N 2225/10 stack temperature
• CPC Class Codes: F23N 2231/20 Warning devices
• CPC Class Codes: F23N 5/242 using electronic means
• CPC Class Codes: F24H 15/174 Supplying heated water with desired temperature or desired range of temperature
• CPC Class Codes: F24H 15/184 Preventing harm to users from exposure to heated water, e.g. scalding
• CPC Class Codes: F24H 15/225 at different heights of the tank
• CPC Class Codes: F24H 15/235 Temperature of exhaust gases
• CPC Class Codes: F24H 15/242 Pressure
• CPC Class Codes: F24H 15/281 Input from user
• CPC Class Codes: F24H 15/31 of valves having only one inlet port and one outlet port, e.g. flow rate regulating valves
• CPC Class Codes: F24H 15/36 of burners
• CPC Class Codes: F24H 15/395 Information to users, e.g. alarms
• CPC Class Codes: F24H 15/421 using pre-stored data
• CPC Class Codes: F24H 15/464 using local wireless communication
• CPC Class Codes: F24H 15/486 using timers
• CPC Class Codes: F24H 9/2035 using fluid fuel
• CPC Class Codes: H04Q 2209/40 using a wireless architecture
• CPC Class Codes: H04Q 2209/823 where the data is sent when the measured values exceed a threshold, e.g. sending an alarm
• CPC Class Codes: H04Q 9/00 Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

Abstract

A control system for a water heater generally includes a water heater controller configured to receive upper and lower sensor temperatures associated with water in the respective upper and lower portions of the tank. The water heater controller is configured to determine a value indicative of a portion of water in the tank at a desired set-point temperature as a function of the upper sensor temperature, the lower sensor temperature, and the desired set-point temperature. The water heater controller is configured to wirelessly transmit at least one signal indicative of said value indicative of the portion of water in the tank at the desired set-point temperature. A user interface includes a plurality of selectively illuminated segmented portions. The user interface is configured to receive said value from the water heater controller and to selectively illuminate a number of segmented portions representative of said value.

Claims

1. A control system for a water heater having a tank, the control system comprising:

a lower sensor disposed to sense a temperature associated with water in a lower portion of the tank of the water heater;

an upper sensor disposed to sense a temperature associated with water in an upper portion of the tank;

a water heater controller coupled to the lower sensor and the upper sensor, the water heater controller configured to receive the sensed temperatures from the upper and lower sensors, the water heater controller configured to determine a value as a function of a maximum number of a plurality of selectively-illuminable segmented portions included in a display device, the value being determined based at least partially on a first temperature differential equal to a desired set-point temperature less the upper sensor temperature and a second temperature differential equal to the desired set-point temperature less the lower sensor temperature, the water heater controller configured to wirelessly transmit at least one signal indicative of said value and

the display device including the plurality of selectively-illuminable segmented portions arranged in a linear array, the display device configured to receive the transmitted at least one signal and to selectively illuminate a number of the segmented portions corresponding to said value as a bar gauge depicting water available at the desired set-point relative to a total water volume of the tank.

2. The control system of claim 1, wherein:

the water heater controller is coupled to the water heater, and the display device includes a remote display device mounted in a location spaced apart from the water heater.

3. The control system of claim 1, wherein the water heater controller is configured to determine said value as the maximum number less an offset, and to determine the offset based at least partially on the average of the first temperature differential divided by a differential variable and the second temperature differential divided by the differential variable.

4. The control system of claim 3, wherein the maximum number is an integer value of at least 4.

5. The control system of claim 3, wherein the differential variable is a value of at least 10.

6. The control system of claim 3, where the water heater controller is configured to determine an activation temperature as a function of the differential variable and the desired set-point temperature and to initiate, based on the activation temperature, a heating operation to heat the water in the tank up to the desired set-point temperature.

7. The control system of claim 1, wherein the water heater controller is configured to calculate the value representing the portion of water within the tank at the desired set-point temperature as:

V=N_maximum−

[(T_setpoint−

T_{upper sensor})/T_differential+(T_setpoint−

T_{lower sensor})/T_differential]/2.

8. The control system of claim 1, wherein the upper sensor includes a surface-mounted temperature sensor coupled to the tank of the water heater.

9. The control system of claim 1, wherein the water heater controller includes a RF transceiver configured to wirelessly transmit the at least one signal indicative of said value representing the portion of water in the tank at the desired set-point temperature to a thermostat including the display device.

10. A control system for a water heater appliance including a tank having an upper portion and a lower portion, the control system comprising:

a water heater controller configured to receive an upper sensor temperature associated with water in the upper portion of the tank and to receive a lower sensor temperature associated with water in the lower portion of the tank, the water heater controller configured to determine a value indicative of a portion of water in the tank at a desired set-point temperature as a function of the upper sensor temperature, the lower sensor temperature, the desired set-point temperature, and a maximum number of a plurality of selectively-illuminable segmented portions included in a user interface, the water heater controller configured to wirelessly transmit at least one signal indicative of said value indicative of the portion of water in the tank at the desired set-point temperature; and

the user interface including the plurality of selectively illuminated segmented portions, the user interface configured to receive said value from the water heater controller and to selectively illuminate a number of segmented portions representative of said value as a bar gauge depicting water available at the desired set-point relative to a total water volume of the tank.

11. The control system of claim 10, wherein the water heater controller is configured to determine said value as the maximum number less an offset, and to calculate the offset as the average of a first temperature differential value, which is equal to the set-point temperature less the upper sensor temperature, divided by a differential variable, and the second temperature differential, which is equal to the set-point temperature less the lower sensor temperature, divided by the differential variable.

12. The control system of claim 11, wherein the water heater controller is configured to limit the calculated offset from exceeding the maximum number.

13. The control system of claim 11, wherein the maximum number is an integer value of at least 4.

14. The control system of claim 10, wherein:

the water heater controller is coupled to the water heater; and

the display device includes a remote display device mounted in a location spaced apart from the water heater; and

/or

the user interface is configured to selectively illuminate a number of segmented portions representative of said value, to thereby visually indicate the portion of the water within the tank at the desired set-point temperature.

15. A method for use in indicating a portion of the water within a tank of a water heater at a desired set-point temperature, the water heater including an upper sensor associated with an upper portion of the tank and a lower sensor associated with a lower portion of the tank, the method comprising:

sensing, at the upper sensor, a temperature of water in the upper portion of the tank;

sensing, at the lower sensor, a temperature of water in the lower portion of the tank;

determining, at a water heater controller, a value representing a portion of water within the tank at a desired set-point temperature, based on the upper sensor and lower sensor temperatures and as a function of a maximum number of a plurality of selectively-illuminable segmented portions included in a display device;

wirelessly transmitting said value to the display device; and

selectively illuminating a number of the plurality of illuminable segmented portions corresponding to said value, to thereby indicate the portion of the water within the tank at the desired set-point temperature as a bar gauge depicting water available at the desired set-point relative to a total water volume of the tank.

16. The method of claim 15, wherein determining the value representing the portion of water within the tank at the desired set-point temperature includes calculating a first temperature differential equal to the set-point temperature less the upper sensor temperature and calculating a second temperature differential equal to the set-point temperature less the lower sensor temperature.

17. The method of claim 16, wherein determining the value representing the portion of water within the tank at the desired set-point temperature includes calculating an offset based at least partially on an average of a first temperature differential divided by a differential variable, and the second temperature differential divided by the differential variable.

18. The method of claim 17, wherein determining the value representing the portion of water within the tank at the desired set-point temperature includes subtracting the offset from a maximum number.

19. The method of claim 15, wherein:

selectively illuminating a number of the plurality of illuminable segmented portions includes illuminating each of the plurality of illuminable segmented portions, when the upper sensor and lower sensor temperatures are greater than or equal to the set-point temperature.

20. The method of claim 15, wherein:

the plurality of illuminable segmented portions of the user interface are arranged in a linear array; and

selectively illuminating the number of the plurality of illuminable segmented portions includes illuminating adjacent ones of the plurality of illuminable segmented portions until said number of segmented portions are illuminated.