Tankless Water Heater

• US 20130094840A1
• Filed: 10/17/2011
• Published: 04/18/2013
• Est. Priority Date: 10/17/2011
• Status: Active Grant

• Current Assignee: David E. Seitz
• Original Assignee: David E. Seitz
• Inventors: Harman, Thomas L., Seitz, David E., Dabney, James, Everett, Louis
• Granted Patent: US 9,167,630 B2
• Time in Patent Office: Days
• US Class Current: 392/449
• CPC Class Codes: F24D 17/0089 Additional heating means, e.g. electric heated buffer tanks or electric continuous flow heaters, located close to the consumer, e.g. directly before the water taps in bathrooms, in domestic hot water lines
• CPC Class Codes: F24H 1/102 with resistance
• CPC Class Codes: F24H 1/103 with bare resistances in direct contact with the fluid
• CPC Class Codes: F24H 1/202 with resistances
• CPC Class Codes: F24H 15/184 Preventing harm to users from exposure to heated water, e.g. scalding
• CPC Class Codes: F24H 15/212 Temperature of the water
• CPC Class Codes: F24H 15/246 Water level
• CPC Class Codes: F24H 2250/02 Resistances
• CPC Class Codes: F24H 9/0015 in water channels
• CPC Class Codes: F24H 9/0021 Sleeves surrounding heating elements or heating pipes, e.g. pipes filled with heat transfer fluid, for guiding heated liquid
• CPC Class Codes: F24H 9/1818 Arrangement or mounting of electric heating means
• CPC Class Codes: F24H 9/2028 Continuous-flow heaters
• CPC Class Codes: H05B 2203/021 Heaters specially adapted for heating liquids
• CPC Class Codes: H05B 3/48 heating conductor embedded in insulating material
• CPC Class Codes: H05B 3/78 Heating arrangements specially adapted for immersion heating
• CPC Class Codes: H05B 3/82 Fixedly-mounted immersion heaters

Abstract

A water heater (10) is suitable for point-of-use applications. The water heater includes a tank housing (12) and one or more electrically powered heating elements (18). A water inlet line (20) and a water outlet line (24) may be molded as a unitary structure with the tank housing. The water outlet line includes a lower port (68) and an upper port (70) for mixing water in the outlet line. The housing may be mounted such that its axis is either vertical or horizontal.

Claims

1. A water heater, comprising:

a tank housing having an internal chamber and a central tank axis;

one or more electrically powered heating elements for heating water within the internal chamber;

a water inlet line extending from outside the tank housing through an inlet port in an upper portion of the tank housing; and

a water outlet line extending from two or more outlet ports from the tank housing, a first outlet port being in the upper portion of the tank housing, and a second outlet port being spaced below the first outlet port.

2. A water heater as defined in claim 1, wherein the central tank axis is substantially vertical, and the second outlet port is in a lower portion of the tank housing.

3. A water heater as defined in claim 1, wherein the central tank axis is substantially horizontal, the inlet port and first outlet port are each in the upper portion of the tank, and a diverter diverts fluid from a lower portion of the internal chamber to the second outlet port.

4. A water heater as defined in claim 1, further comprising:

the one or more electrically powered heating elements engaging an end of the tank housing; and

a cap removably secured to the tank housing for access to the internal chamber at a location axially opposite the engagement of the one or more electrically powered heating elements and the end of the tank housing, the cap having an axially extending cavity therein to receive an unsupported end of the one or more electrically powered heating elements.

5. A water heater as defined in claim 1, further comprising:

a controller for controlling power to the one or more heating elements, the controller responsive to a “

flow”

condition based on an absolute value of the change in temperature sensed upstream from the inlet port and the absolute value of the change in the temperature sensed downstream from the first outlet port.

6. A water heater as defined in claim 1, further comprising:

an inlet temperature sensor for sensing water temperature in the water inlet line;

an outlet temperature sensor for sensing water temperature in the water outlet line; and

a controller responsive to the inlet temperature sensor and the outlet temperature sensor for controlling power to the one or more electrically powered heating elements.

7. A water heater as defined in claim 1, wherein an electrical capacity of the one or more electrically powered heaters in kilowatts is from 2 kW to 10 kW, and the volume of the internal chamber containing the heater is from 20 ounces to 80 ounces.

8. A water heater as defined in claim 1, wherein a portion of the water outlet line shares a common wall with the tank housing;

and

a vent hole in the housing venting air from the chamber to the water outlet line when the tank axis is substantially vertical, and venting air from the chamber to the water outlet line when the tank axis is substantially horizontal.

9. A water heater as defined in claim 1, wherein a portion of the water inlet line shares a common wall with the tank housing.

10. A water heater as defined in claim 1, wherein each of the water inlet line and the water outlet line are integral with the tank housing, and are spaced circumferentially within a quadrant of the tank housing.

11. A water heater as defined in claim 1, wherein the tank housing, water inlet line, and the water outlet line are molded as a unitary and monolithic structure.

12. A water heater as defined in claim 1, further comprising:

a diverter within the interior chamber in fluid communication with the second outlet port, the diverter extending substantially inward from the second outlet port into the internal chamber, and having an inlet opening to receive heated water from a lower portion of the internal chamber.

13. A water heater as defined in claim 1, wherein an inlet to the water inlet line and an outlet from the water outlet line are each spaced at least 50% of a diameter of the cylindrical chamber from any portion of the tank housing.

14. A water heater as defined in claim 1, wherein an interior diameter of each of the water inlet line and the water outlet line is greater than 0.6 inches, and the tank housing interior diameter is greater than 2.0 inches.

15. A water heater, comprising:

a tank housing having an internal chamber and a central tank axis;

one or more electrically powered heating elements for heating water within the interior chamber;

a water inlet line extending from outside the tank housing to an inlet port in a side of the tank housing;

a water outlet line extending from an outlet port in a side of the tank housing to the exterior of the tank housing; and

each of the water inlet line and the water outlet line are integral with the tank housing, and are spaced circumferentially within a quadrant of the tank housing.

16. A water heater as defined in claim 15, further comprising:

a diverter within the internal chamber in fluid communication with the second outlet port, the diverter extending substantially inward from the second outlet port into the interior chamber, and having an inlet opening to receive heated water from a lower first portion of the chamber, and from a generally axially centered second portion of the chamber when the tank axis is substantially horizontal.

17. A water heater as defined in claim 15, wherein the tank housing, water inlet line, and the water outlet line are molded as a unitary and monolithic structure.

18. A water heater as defined in claim 15, wherein the one or more electrically powered heating elements engage an end of the tank housing;

and

a cap removably secured to the tank housing for access to the internal chamber at a location axially opposite the engagement of the one or more electrically powered heating elements and the tank housing, the cap removably secured to the tank housing for access to the internal chamber at a location axially opposite the engagement of the one or more electrically powered heating elements and the end of the tank housing, the cap having an axially extending cavity therein to receive an unsupported end of the one or more electrically powered heating elements.

19. A water heater as defined in claim 15, wherein an interior diameter of each of the water inlet line and the water outlet line is greater than 0.6 inches, and the tank housing interior diameter is greater than 2.0 inches.

20. A method of heating, comprising:

providing a tank housing having an internal chamber and a central tank axis;

providing a water inlet line extending from outside the tank housing to an inlet port in a side of the tank housing;

providing a water outlet line extending from the tank housing to the exterior of the tank housing, the water outlet line having two or more ports in the tank, a first outlet port being in the upper portion of the tank, and a second outlet port being spaced substantially below the first outlet port; and

providing one or more electrical heating elements for heating water within the interior chamber.

21. A method as defined in claim 20, further comprising:

providing a diverter within the interior chamber in fluid communication with the outlet port, the diverter extending substantially inward from the outlet port into the interior chamber, and having an inlet opening to receive heated water from a lower first portion of the chamber when the tank axis is substantially vertical, and from a generally axially centered second portion of the chamber.

22. A method as defined in claim 20, further comprising:

providing an electrical capacity of the one or more electrically powered heaters in kW is from 2 kW to 10 kW, and the volume of the internal chamber containing the heater is from 20 ounces to 80 ounces.

23. A method as defined in claim 20, further comprising:

sensing the temperature of water in the water inlet line;

sensing the temperature of water in the water outlet line; and

providing a controller responsive to the sensed inlet temperature and the sensed outlet temperature for controlling power to one or powered heating elements.

24. A method as defined in claim 20, wherein a portion of the water outlet line shares a common wall with the tank housing;

and

venting air from the chamber through a vent port to the water outlet line when the tank axis is substantially vertical, and venting air from the chamber through the vent port to the outer outlet line when the tank axis is substantially horizontal.

25. A method as defined in claim 20, wherein each of the water inlet line and the water outlet line are integral with the tank housing, and are spaced circumferentially within a quadrant of the tank housing.

26. A method as defined in claim 20, further comprising:

forming the tank housing, the water inlet line, the water outlet line as a unitary and monolithic structure.

27. A method as defined in claim 20 wherein an interior diameter of each of the water inlet line and the water outlet line is greater than 0.6 inches, and the tank housing interior diameter is greater than 2.0 inches.

28. A water heater, comprising:

a tank housing having an internal chamber and a central tank axis;

one or more electrically powered heating elements for heating water within the internal chamber;

a water inlet line extending from outside the tank housing to an inlet port;

a water outlet line extending from an outlet port in the tank; and

a controller for controlling power to the one or more heating elements, the controller responsive to a “

flow”

condition based on an absolute value of the change in temperature sensed upstream from the inlet port and the absolute value of the change in the temperature sensed downstream from the first outlet port.

29. A water heater as defined in claim 28, wherein a portion of the water inlet line shares a common wall with the tank housing.

30. A water heater as defined in claim 28, wherein each of the water inlet line and the water outlet line are integral with the tank housing, and are spaced circumferentially within a quadrant of the tank housing.

31. A water heater as defined in claim 28, wherein the one or more electrically powered heating elements engage to an end of the tank housing;

and

a cap removably secured to the tank housing for access to the internal chamber at a location axially opposite the engagement of the one or more electrically powered heating elements and the end of the tank housing.

32. A water heater as defined in claim 28, further comprising:

a diverter within the interior chamber in fluid communication with the second outlet port, the diverter extending substantially inward from the second outlet port into the internal chamber, and having an inlet opening to receive heated water from a central portion of the internal chamber.

33. A water heater, comprising:

a generally cylindrical tank housing having an internal chamber and a central tank axis;

one or more electrically powered heating elements for heating water within the internal chamber and engaging an end of the tank housing;

a water inlet line extending from outside the tank housing through an inlet port in an upper portion of the tank housing;

a water outlet line extending from an axially spaced outlet port from the tank housing;

a seal ring for sealing between the one or more heating elements and the tank housing; and

a gland threaded to the tank housing for forcing the one or more heating elements into sealing engagement with the seal thereby isolating the gland/housing threads from water in the internal chamber.

34. A water heater as defined in claim 33, further comprising:

a cap removably secured to the tank housing for access to the internal chamber at a location axially opposite the engagement of the one or more electrically powered heating elements and the end of the tank housing.

35. A water heater as defined in claim 33, further comprising:

an inlet temperature sensor for sensing the temperature of water in the water inlet line;

an outlet temperature sensor for sensing the temperature of water in the water outlet line; and

a controller responsive to the inlet temperature sensor and the outlet temperature sensor for controlling power to one or more electrical powered heating elements.

36. A water heater as defined in claim 33 further comprising:

a controller for controlling power to the one or more heating elements, the controller responsive to a “

flow”

condition based on an absolute value of the change in temperature sensed upstream from the inlet port and the absolute value of the change in the temperature sensed downstream from the first outlet port.

37. A water heater as defined in claim 33, wherein each of the water inlet line and the water outlet line are integral with the tank housing, and are spaced circumferentially with a quadrant of the tank housing.

38. A water heater as defined in claim 33, wherein the tank housing, water inlet line, and the water outlet line are molded as a unitary and monolithic structure.