WATER HEATING SYSTEMS AND METHODS
A water heating system has a controller that is electronically actuated. In this regard, the controller controls an activation state of at least one heating element by providing an electrical control signal to a relay. In one embodiment, the controller has an emergency shut-off apparatus that is mechanically actuated. Further various features can be optionally implemented to help heat related problems plaguing many conventional water heater controllers that are electronically actuated.
1 . A water heater controller, comprising:
a relay for controlling an activation state of a heating element;
an emergency shut-off apparatus for disabling the heating element if a temperature exceeds a threshold, the emergency shut-off apparatus having a temperature sensitive element that mechanically actuates based on the temperature, the emergency shut-off apparatus having a mechanical switch that is coupled to the relay, wherein actuation of the temperature sensitive element changes a state of the switch; and
logic configured to receive temperature data indicative of a temperature sensed by a temperature sensor, the logic further configured to control a state of the relay based on the temperature data.
2 . The water heater controller of claim 1 , wherein the logic is configured to perform a comparison between the temperature data and a threshold value, wherein the logic is configured to transmit an electronic signal to the relay based on the comparison, and wherein the relay transitions from an open state to a closed state in response to the electronic signal thereby activating the heating element.
3 . The water heater controller of claim 1 , wherein the logic is configured to perform a comparison between the temperature data and a threshold value, wherein the logic is configured to transmit an electrical signal to the relay based on the comparison, and wherein the relay transitions from a closed state to an open state in response to the electronic signal thereby deactivating the heating element.
4 . The water heater controller of claim 1 , wherein the emergency shut-off apparatus, upon disabling the heating element, is configured to ensure that the heating element remains disabled until at least the emergency shut-off apparatus receives a user input.
5 . The water heater controller of claim 1 , wherein the temperature sensitive element comprises a bimetallic disc.
6 . The water heater controller of claim 1 , further comprising an electrically conductive connection coupled to the emergency shut-off apparatus, the connection composed of a metallic alloy having an International Annealed Copper Standard (IACS) of greater than 80%, a stress relaxation temperature greater than 105 degrees Celsius, and a yield stress greater than 50 kilo-pounds per square inch (ksi).
7 . The water heater controller of claim 1 , further comprising:
a thermally conductive base;
a housing coupled to the base, the housing composed of electrically insulating material;
the temperature sensor, wherein the temperature sensor contacts the base.
8 . The water heater controller of claim 7 , wherein the relay is mounted on a first side of a printed circuit board (PCB), and wherein the temperature sensor is positioned on a second side of the PCB that is opposite to the first side.
9 . The water heater controller of claim 7 , wherein the temperature sensor is mounted on an element composed of thermally insulating material and is electrically coupled to the PCB.
10 . The water heater controller of claim 1 , further comprising an interface for electrically connecting an electrically conductive wire to an electrically conductive connection, the interface having a hole for receiving the wire.
11 . The water heater controller of claim 10 , wherein the connection is coupled to the emergency shut-off apparatus.
12 . The water heater controller of claim 10 , wherein the connection is coupled to the relay.
13 . The water heater controller of claim 10 , wherein the connection has at least one rib for guiding the wire as the wire is being inserted into the first hole.
14 . The water heater controller of claim 10 , further comprising a housing covering the logic, the housing having a hole, wherein the wire has a coating composed of insulating material, and wherein a portion of the coating passes through the hole of the housing.
15 . The water heater controller of claim 14 , wherein at least a portion of a wall of the housing contacts the coating, the portion defining the hole of the housing.
16 . The water heater controller of claim 14 , wherein the interface is composed of a metallic alloy having an International Annealed Copper Standard (IACS) of greater than 80%, a stress relaxation temperature greater than 105 degrees Celsius, and a yield stress greater than 50 kilo-pounds per square inch (ksi).
17 . The water heater controller of claim 10 , further comprising:
a thermally conductive base;
a housing coupled to the base, the housing composed of an electrically insulating material;
the temperature sensor,
wherein the temperature sensor contacts the base.
18 . The water heater controller of claim 17 , wherein the relay is mounted on a first side of a printed circuit board (PCB), and wherein the temperature sensor is positioned on a second side of the PCB that is opposite to the first side.
19 . The water heater controller of claim 18 , wherein the temperature sensor is mounted on an element composed of thermally insulating material and electrically coupled to the PCB.
20 . A water heating system, comprising:
a tank;
a heating element mounted on the tank; and
a controller mounted on the tank, the controller comprising:
an emergency shut-off apparatus that is mechanically actuated, the emergency shut-off apparatus coupled to the heating element and having a temperature sensitive element that mechanically actuates due to thermal stresses such that the heating element is disabled if the temperature exceeds a threshold;
a relay coupled to the heating element; and
logic configured to receive temperature data indicative of a temperature sensed by a temperature sensor, the logic further configured to control a state of the relay based on the temperature data.
21 . The system of claim 20 , wherein the controller further comprises:
a thermally conductive base;
a housing coupled to the base, the housing composed of electrically insulating material;
the temperature sensor,
wherein the temperature sensor contacts the base.
22 . The system of claim 21 , wherein the relay is mounted on a first side of a printed circuit board (PCB), and wherein the temperature sensor is positioned on a second side of the PCB that is opposite to the first side.
23 . The system of claim 20 , further comprising an electrically conductive wire, wherein the controller further comprises:
an electrically conductive connection; and
an interface having a hole, the connection extending through the hole.
24 . The system of claim 23 , further comprising a housing covering the logic, the housing having a hole, wherein the wire has a coating composed of insulating material, and wherein a portion of the coating passes through the hole of the housing.
25 . The system of claim 23 , wherein the connection is composed of a metallic alloy having an International Annealed Copper Standard (IACS) of greater than 80%, a stress relaxation temperature greater than 105 degrees Celsius, and a yield stress greater than 50 kilo-pounds per square inch (ksi).
26 . The system of claim 23 , wherein the connection has at least one rib for guiding the wire as the wire is being inserted into the first hole.
27 . A water heater controller, comprising:
an electromechanical switching means for controlling an activation state of the heating element;
means for disabling a heating element if a temperature exceeds a threshold, the disabling means having a mechanical switching means coupled to the relay and having a temperature sensing means that mechanically actuates based on the temperature, wherein actuation of the temperature sensing means changes a state of the mechanical switching means; and
means for receiving temperature data indicative of a temperature sensed by a temperature sensor, and for controlling a state of the relay based on the temperature data.
28 . A method for controlling a water heating system having a tank and a heating element mounted on the tank, comprising the steps of:
disabling the heating element if a temperature exceeds a threshold, the disabling step comprising the step of mechanically actuating a temperature sensitive element based on the temperature;
sensing a temperature;
transmitting temperature data indicative of the sensed temperature; and
controlling an operational state of the heating element based on the temperature data, the controlling step comprising the step of electrically actuating a relay based on the temperature data.
29 . The method of claim 28 , wherein the disabling step comprises the step of ensuring that the heating element remains disabled until a user input is received.