David Roy Seitz

US Patent:

7616873, Nov 10, 2009

Filed:

Apr 8, 1993

Appl. No.:

08/044650

Inventors:

David E. Seitz - Houston TX, US

International Classification:

F24H 1/10

US Classification:

392490, 392486, 219497

Abstract:

A flow-through instantaneous fluid heater system is designed to satisfy the need for a heater not limited by being connected to a storage tank and which can be made using a plastic casing, incorporating cool-down when out of service and with features of venting and simplified flushing and draining. The system incorporates the use of one or more compartments, usually assembled in two compartment modules connected in series. Each compartment includes a casing having a hollow cylindrical interior region. An inlet aperture is located at one end of the casing and an outlet aperture is located at the other end of the casing. The lower end of each casing is closed by a removable base and the upper end of the casing is closed by a top plate and a heating element. The heating element is positioned axially in the interior region of the compartment. The heating element is activated by a control system which senses and compares temperatures of the water at the compartment outlets.

US Patent:

62468316, Jun 12, 2001

Filed:

Jun 16, 1999

Appl. No.:

9/334337

Inventors:

David E. Seitz - Conroe TX
David Paul Sharp - Houston TX
Thomas Lamson Harman - Houston TX
Louis J. Everett - College Station TX
Rodney H. Neumann - The Woodlands TX

Assignee:

David Seitz - Houston TX

International Classification:

F24H 110

US Classification:

392486

Abstract:

An improved system, method and apparatus for control of an instantaneous flow-through fluid heater system is disclosed. The control incorporates a logic control method providing modulation of power in small steps to a plurality of heating elements retaining responsiveness to closed-loop control needs without inducing light flicker. Further, the life of the coils of heating circuit electromechanical relays are extended by energizing the coils with a pulse-width-modulated drive decreasing in duty cycle and thus the latent coil heat when an increase in mains voltage is sensed. The life of the contacts of same relays are extended by inhibiting heating element triac drive immediately upon sensing loss of relay coil power, such as by an over temperature limit switch opening, thus ensuring that relay contacts open with zero heating element current. In addition to the software "watchdog timer" internal to the microcontroller, a redundant fail-safe circuit external to the microcontroller prevents a program lockup condition from leaving any heating element triac or relay drive in an energized state. A combination of control hardware and program provide self-diagnostic detection of an inoperative thermistor, stuck relay, or a failed triac or heating element.

US Patent:

52167437, Jun 1, 1993

Filed:

May 10, 1990

Appl. No.:

7/521541

Inventors:

David E. Seitz - Houston TX

International Classification:

F24H 110

US Classification:

392490

Abstract:

The present invention provides a flow-through instantaneous fluid heater system designed to satisfy the need for a heater not limited by being connected to a storage tank and which can be made using a plastic casing, incorporating cool-down when out of service and with features of venting and simplified flushing and draining. The system incorporates the use of one or more compartments, usually assembled in two compartment modules connected in series. Each compartment includes a casing having a hollow cylindrical interior region. An inlet aperture is located at one end of the casing and an outlet aperture is located at the other end of the casing. The lower end of each casing is closed by a removable base and the upper end of the casing is closed by a top plate and a heating element. The heating element is positioned axially in the interior region of the compartment. The heating element is activated by a control system which senses and compares temperatures of the water at the compartment outlets.

US Patent:

6080971, Jun 27, 2000

Filed:

Feb 1, 1999

Appl. No.:

9/241185

Inventors:

David Seitz - Conroe TX
Donald Kuhnel - Hobson TX

International Classification:

H05B 102

US Classification:

219483

Abstract:

An electrically powered water heater includes a plurality of heating elements for substantially instantaneous heating of fluid passing through the heater. A controller for powering the plurality of heating elements is responsive to a temperature sensor in fluid communication with the heated fluid. The temperature sensor activates each of the plurality of heating elements for a predetermined period of time that is preferably no more than 32 half cycles. The controller activates a second heating element after a delay of preferably no more than 8 half cycles after activating a first heating element. The predetermined period of time for activating each of the plurality of heating elements may be substantially equal, such that each heating element contributes substantially equally to the heating of fluid. In one embodiment, the heater housing is provided with a plurality of chambers, and a heating element is provided within each of the plurality of chambers.

US Patent:

58668802, Feb 2, 1999

Filed:

May 22, 1997

Appl. No.:

8/861766

Inventors:

David Seitz - Conroe TX
Donald Kuhnel - Hobson TX

International Classification:

H05B 102

US Classification:

219483

Abstract:

An electrically powered water heater includes a plurality of heating elements for substantially instantaneous heating of fluid passing through the heater. A controller for powering the plurality of heating elements is responsive to a temperature sensor in fluid communication with the heated fluid. The temperature sensor activates each of the plurality of heating elements for a predetermined period of time that is preferably no more than 32 half cycles. The controller activates a second heating element after a delay of preferably no more than 8 half cycles after activating a first heating element. The predetermined period of time for activating each of the plurality of heating elements may be substantially equal, such that each heating element contributes substantially equally to the heating of fluid. In one embodiment, the heater housing is provided with a plurality of chambers, and a heating element is provided within each of the plurality of chambers.