Hot water heater systems and methods for controlling electronic mixing valves

Patent metadata

Field	Value
Publication number	US-9696043-B2
Application number	US-201514641495-A
Country	US
Kind code	B2
Filing date	Mar 9, 2015
Priority date	Mar 9, 2015
Publication date	Jul 4, 2017
Grant date	Jul 4, 2017

Abstract

Hot water heater systems and methods for controlling electronic mixing valves of hot water heater systems are disclosed. An electronic mixing valve provides a flow of water in a mixed output line. A method includes determining a temperature value inside a hot water tank of the hot water heater, and comparing the hot water tank temperature value to a setpoint temperature value. The method further includes comparing a temperature value for water in the mixed output line to a lower setpoint threshold value when the hot water tank temperature value is greater than the setpoint temperature value, wherein the lower setpoint threshold value is less than the setpoint temperature, and setting the electronic mixing valve to a safe position wherein the electronic mixing valve is less than fully open when the temperature value for water in the mixed output line is less than the lower setpoint threshold value.

First claim

What is claimed is:

1. A method for controlling an electronic mixing valve for a hot water heater, the electronic mixing valve providing a flow of water in a mixed output line, the method comprising:
determining a temperature value inside a hot water tank of the hot water heater;
comparing the hot water tank temperature value to a setpoint temperature value; and
comparing a temperature value for water in the mixed output line to a lower setpoint threshold value when the hot water tank temperature value is greater than the setpoint temperature value, wherein the lower setpoint threshold value is less than the setpoint temperature; and
setting the electronic mixing valve to a safe position wherein the electronic mixing valve is less than fully open when the temperature value for water in the mixed output line is less than the lower setpoint threshold value.

2. The method of claim 1 , wherein the safe position is a first safe position, and further comprising:
comparing the temperature value for water in the mixed output line to an upper setpoint threshold value when the hot water tank temperature value is greater than the setpoint temperature value, wherein the upper setpoint threshold value is greater than the setpoint temperature; and
setting the electronic mixing valve to a second safe position wherein the electronic mixing valve is less than fully open when the temperature value for water in the mixed output line is greater than the upper setpoint threshold value.

3. The method of claim 2 , wherein comparing the temperature value for water in the mixed output line to the upper setpoint threshold value occurs when the temperature value for water in the mixed output line is greater than the lower setpoint threshold value.

4. The method of claim 2 , wherein the second safe position is less open than the first safe position.

5. The method of claim 1 , further comprising determining whether a temperature of the water in the mixed output line requires adjustment, and
wherein determining the temperature value inside the hot water tank occurs when the temperature of the water in the mixed output line requires adjustment.

6. The method of claim 5 , wherein determining whether the temperature of the water in the mixed output line requires adjustment comprises comparing a temperature error value to a temperature tolerance, and wherein the temperature of the water in the mixed output line requires adjustment when the temperature error value is greater than the temperature tolerance.

7. The method of claim 6 , further comprising:
determining the temperature value for water in the mixed output line; and
comparing the temperature value for water in the mixed output line to the setpoint temperature to determine the temperature error value.

8. A method for controlling an electronic mixing valve for a hot water heater, the electronic mixing valve providing a flow of water in a mixed output line, the method comprising:
determining a temperature value inside a hot water tank of the hot water heater;
comparing the hot water tank temperature value to a setpoint temperature value; and
comparing a temperature value for water in the mixed output line to an upper setpoint threshold value when the hot water tank temperature value is greater than the setpoint temperature value, wherein the upper setpoint threshold value is greater than the setpoint temperature; and
setting the electronic mixing valve to a safe position wherein the electronic mixing valve is less than fully open when the temperature value for water in the mixed output line is greater than the upper setpoint threshold value.

9. The method of claim 8 , further comprising determining whether a temperature of the water in the mixed output line requires adjustment, and
wherein determining the temperature value inside the tank of the hot water heater occurs when the temperature of the water in the mixed output line requires adjustment.

10. A hot water heater system, comprising:
a hot water tank having a cold water inlet line and a hot water outlet line;
an electronic mixing valve fluid coupled to the cold water inlet line and the hot water outlet line;
a mixed output line fluidly coupled to the electronic mixing valve; and
a controller operatively coupled to the electronically controlled mixing valve and operable to:
determine a temperature value inside the hot water tank;
compare the hot water tank temperature value to a setpoint temperature value; and
compare a temperature value for water in the mixed output line to a lower setpoint threshold value when the hot water tank temperature value is greater than the setpoint temperature value, wherein the lower setpoint threshold value is less than the setpoint temperature; and
set the electronic mixing valve to a safe position wherein the electronic mixing valve is less than fully open when the temperature value for water in the mixed output line is less than the lower setpoint threshold value.

11. The hot water heater system of claim 10 , wherein the safe position is a first safe position, and wherein the controller is further operable to:
compare the temperature value for water in the mixed output line to an upper setpoint threshold value when the hot water tank temperature value is greater than the setpoint temperature value, wherein the upper setpoint threshold value is greater than the setpoint temperature; and
set the electronic mixing valve to a second safe position wherein the electronic mixing valve is less than fully open when the temperature value for water in the mixed output line is greater than the upper setpoint threshold value.

12. The hot water heater system of claim 11 , wherein comparing the temperature value for water in the mixed output line to the upper setpoint threshold value occurs when the temperature value for water in the mixed output line is greater than the lower setpoint threshold value.

13. The hot water heater system of claim 11 , wherein the second safe position is less open than the first safe position.

14. The hot water heater system of claim 10 , wherein the controller is further operable to determine whether a temperature of the water in the mixed output line requires adjustment, and
wherein determining the temperature value inside the hot water tank of the hot water heater occurs when the temperature of the water in the mixed output line requires adjustment.

15. The hot water heater system of claim 14 , wherein determining whether the temperature of the water in the mixed output line requires adjustment comprises comparing a temperature error value to a temperature tolerance, and wherein the temperature of the water in the mixed output line requires adjustment when the temperature error value is greater than the temperature tolerance.

16. The hot water heater system of claim 15 , wherein the controller is further operable to:
determine the temperature value for water in the mixed output line; and
compare the temperature value for water in the mixed output line to the setpoint temperature to determine the temperature error value.

17. The hot water heater system of claim 10 , further comprising a temperature sensor operatively coupled to the mixed output line and the controller, and wherein the temperature value for water in the mixed output line is determined based on signals received from the temperature sensor.

18. The hot water heater system of claim 17 , wherein the temperature sensor is a thermistor.

19. The hot water heater system of claim 10 , further comprising a temperature se

Assignees

• Gen Electric
• Haier Us Appliance Solutions Inc

Inventors

• Ward Shaun Michael
• Powers Jacob Gregory

Classifications

• F24D19/1051 Primary

  for domestic hot water · CPC title

• G05D23/134

  measuring the temperature of mixed fluid · CPC title

• F24H15/315

  of mixing valves · CPC title

• F24H15/175

  where the difference between the measured temperature and a set temperature is kept under a predetermined value · CPC title

• F24H15/215

  before heating · CPC title