TECHNICAL FIELD

[0001] This disclosure is generally directed to a heating system, such as an immersion heater. More specifically, this disclosure is related to a heating system having immersion type heaters.

BACKGROUND

[0002] Tank heating systems are designed to heat large storage tanks containing fluids or heat sensitive materials, such as water or any viscous fluids. Tank heating systems are used in a wide variety of industries where heated liquids are used in processing or production processes, for example, in surface finishing applications and plating applications. Conventionally, a heating tank has multiple heaters operating in an individual (solo) mode to heat/maintain the temperature of the liquid contained therein. In the conventional setup, if the tank temperature goes down or if any undesired temperature variation occurs, it is difficult to identify which heater is causing the problem. In this situation, the entire tank heating system needs to be shut down so that each heater can be tested individually (e.g., with a multimeter for electrical resistance) to resolve the issue and/or to replace it. This is time consuming, inefficient, costly, and creates difficulties in the operation floor. As the heaters are operating individually, it is also difficult to identify and monitor the health of the heaters in the tank.

SUMMARY

[0003] A heating system includes heaters configured to heat a liquid contained in a tank. Each of the heaters includes a heating element, a temperature sensor coupled to the heating element, a control unit in communication with the heating element and the temperature sensor. The control unit is configured to control the heating element and the temperature sensor. The heating system includes a smart probe in communication with the control unit of one of the heaters and configured to monitor operation conditions of the heating system. The heating system includes a display and an indicator coupled to the control unit. The heaters are integrated in a mesh network operatable under Intemet-of-Things (loT) connectivity. [0004] The control units are configured to shut down one or more heaters if any shutdown protocols are triggered. The shutdown protocols include that the control unit includes a system- on-chip (SOC) configured to read the temperature sensor and configured to shut down the heater when the sensor detects a temperature above a pre-determined temperature. The shutdown protocols include that the control unit receives a communication from the smart probe indicating an operation condition outside a pre-determined range.

[0005] The smart probe includes one or more sensors configured to monitor the operation conditions including a temperature of the liquid. The smart probe includes one or more sensors configured to monitor the operation conditions including presences and/or concentrations of volatile organic compounds (VOCs), a pH level of the liquid, and/or chemical composition and/or concentration of the liquid. The heaters and the smart probe are configured such that the smart probe can be coupled to any of the heaters.

[0006] The heating system is configured to send a process data log to a user via email. The heating system is configured to send operation information to a user. The operation information includes safety alerts, notifications and/or reset instructions, the operation conditions monitored by the smart probe, heater failure, heater overtemperature, and/or heater maintenance schedule.

[0007] A computer-implemented method of operating a heating system including multiple heaters configured to heat a liquid contained in a tank. The method includes confirming presences of heater safety shutdown mechanisms that are built-in in firmware of each of the multiple heaters and a smart probe coupled to one of the multiple heaters. The method includes starting operation of the multiple heaters upon a determination that the heater safety shutdown mechanisms are present and shutting down a heater of the multiple heaters upon a determination that at least one of the heater safety shutdown mechanisms pertained to the heater is triggered. The method includes notifying a user about a heater shutdown and re-starting the heater upon a determination that problems pertained to the triggered heater safety shutdown mechanism have been resolved.

[0008] The heater safety shutdown mechanisms include that in each of the multiple heaters, a heating element of the heater is connected to a thermal-cut-off (TCO) switch; a system-on-chip (SOC) is configured to read a temperature sensor coupled to each of the multiple heaters and is configured to shut down the heater when the temperature sensor detects a temperature above a pre- determined temperature; and the smart probe detects an operation condition outside a predetermined range.

[0009] Other elements of the method include sending reset instructions to the user to reset the shutdown heater and refdling the liquid to the tank via a drain valve upon a determination that a liquid level is below a pre-determined liquid level.

[0010] Other elements of the method include draining the tank via a drain valve upon a determination that a liquid level is above a pre-determined liquid level and sending maintenance reminders to the user upon a determination that the heating system has been running for a predetermined number of hours.

[0011] An immersion heater includes a heating element configured to heat a liquid, a temperature sensor coupled to the heating element, and a control unit in communication with the heating element and the temperature sensor. The control unit is configured to control the heating element and the temperature sensor, and the control unit is configured to communicate with, and control, at least one secondary control unit of a secondary immersion heater.

[0012] The control unit is configured to communicate with, and monitor, a smart probe. The smart probe is configured to monitor the operation conditions including a temperature of the liquid. The control unit is configured to shut down the heating element and/or the secondary immersion heater if any shutdown protocols are triggered. The control unit is configured to send operation information to a user device. The operation information includes one of safety alerts, notifications, reset instructions, the operation conditions monitored by the smart probe, heater failure, heater overtemperature, and heater maintenance schedule.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. l is a schematic of an example heating system;

[0014] FIG. 2A and FIG. 2B are perspective front and rear views of an example heater, respectively;

[0015] FIG. 3 is a schematic of an example connector with programmable auxiliary control outputs for the heating system; [0016] FIG. 4 shows schematics of example start-up screens of the heating system;

[0017] FIG. 5 shows schematics of example standard operation screens of the heating system;

[0018] FIG. 6 shows an example process performed by the heating system;

[0019] FIG. 7 shows schematics of example heater overtemperature alert screens of the heating system; and

[0020] FIG. 8 shows schematics of example tank fdl screen and drain cycle screen of the heating system;

DETAILED DESCRIPTION

[0021] Conventional tank heating systems are prone to having costly down-times (e.g., due to the challenges to identify and monitor the heath and condition of individually operating heaters) and prone to causing accidents due to operational errors. The present disclosure is directed to a smart heating system that is configured to overcome the disadvantages of conventional tank heating systems. The heating system disclosed herein is capable of operating autonomously without external controls in an easy set-and-forget mode and brings a new level of control and monitoring.

[0022] The heating system disclosed herein is configured to offer heating and advanced process control with Intemet-of-Things (IoT) technology. For example, the heating system disclosed herein is an autonomous system that can operate without external controls. The setup is simple and can be easily done from any smart device and/or using an interactive display of the heating system. User-programmable schedules are available for daily operations, and the system offers real-time temperature and safety system monitoring and process data log accessibility to users. The heating system is configured to provide multi-layered safety control. Multiple, redundant safety mechanisms/protocols (e.g., thermal cut off switch or TCO, thermal TC protector, and liquid level control mechanisms) are built-in and heaters would not operate if any of the safety mechanisms/protocols is triggered or tempered. [0023] The multiple heaters of the heating system disclosed herein are integrated in a mesh network. Additional heaters may be easily added to the mesh network. The heating system disclosed herein also offers programmable maintenance schedule and alerts and notifications of failed heating elements. The heating system disclosed herein is able to achieve improved heating quality through advanced process control, for example, by assuring safety operation of the heating system and increasing uptime with automatic real-time alerts.

[0024] FIG. 1 shows an example of a heating system 100 for heating a liquid 102 contained in a tank 104. The tank 104 includes a liquid level valve or a fill valve 103 (e.g., an electrical valve that allows filling of the liquid 102 in the tank 104) and includes a drain valve 105 (e.g., an electrical valve that allows draining of the liquid 102 from the tank 104). The heating system 100 includes heaters 106 and a smart probe 108 connected to one of the heaters 106. The heaters 106 are connected (e.g., via a wired or wireless connection) to one another, forming a mesh heater network 110. For example, the heaters 106 are communicatively and/or operatively coupled to each other via a power cable/wire 112 and via a wireless communication network 114 (e.g., WiFi and/or Bluetooth). The power cable/wire 112 may be connected to an electric outlet or power source to supply power to the heating system 100. The power cable/wire 112 may be connected to a ground fault protection system 113, a junction box branch circuit protection 115, and/or a fused disconnect mechanism 117. It should be noted that although only one of the heaters 106 is connected with the smart probe 108, all of the heaters 106 are configured to be connectable with the smart probe 108. There may be any suitable number of heaters 106 in the mesh heater network 110, e.g., two, three, four, five.. . twelve, or greater than twelve.

[0025] Each of the heaters 106 includes a heating element 116, a sensor 118 (e.g., a temperature sensor) and a control unit 120. The heating element 116 (e.g., heating plate, heating tube, etc.) is configured to at least partially immerse in the liquid 102 to heat and/or maintain a temperature of the liquid 102. The sensor 118 is configured to monitor at least a temperature of the liquid 102. The control units 120 are configured to operate the respective heater 106. The control units 120 are also capable of processing information/data, controlling, and coordinating operations of the heaters 106 within the mesh heater network 110 and communicating heating system related information to users (e.g., alerts, real-time monitoring information, process data log, heater failure, overheating, notice of failure heating elements 116, maintenance schedule and reminders, etc ). The control units 120 are configured to provide Tntemet-of-Things (ToT) based controls of the heating system 100. The control unit 120 of the heater 106 connected to the smart probe 108 is referred to as a master control unit 121 which processes information/data, controls, and coordinates operations of the heaters 106 within the mesh heater network 110 and communicates heating system related information to users.

[0026] The smart probe 108 is coupled to one of the heaters 106 via a wired connection 122 or via the wireless communication network 114 (e.g., WiFi and/or Bluetooth). In one embodiment, the wired connection 122 is within the user equipment connection cable 302 and the connector 300. The smart probe 108 includes one or more sensors 124 configured to monitor various conditions of the heating system 100, e.g., liquid temperature, liquid level, liquid pH level, chemical composition and concentrations of the liquid 102, carbon monoxide (CO) and/or carbon dioxides (CO2) detection, smoke detection, volatile organic compound (VOC) detection, etc. In one embedment, the one or more sensors 124 may be metal probe sensors. In another embodiment, the one or more sensors 124 may be ultrasonic sensors, infrared sensors, and/or capacitance sensors.

[0027] The heater 106 that is connected to the smart probe 108 is referred to as a master heater 126 and the control unit 120 of the master heater 126 is referred to as the master control unit 121 . The master heater 126 is capable of receiving the various sensory data from the smart probe 108 which allows coordination of the heater operations of the entire mesh heater network 110. The heaters 106 that are not connected to the smart probe 108 are referred to as secondary heaters 128. The master heater 126 and the secondary heaters 128 are identical (e.g., including the same components or capable of performing the same functions), and the only difference is that the master heater 126 is connected to the smart probe 108. It should be appreciated that if the current heater 106 connected to the smart probe 108 fails, any of the other heaters 106 may be connected to the smart probe 108 and become the master heater 126.

[0028] Any authorized smart devices 130 (e g., cell phone, computer, laptop, tablet device, etc.) can be connected to the heating system 100 through the wireless communication network 114 (e g , WiFi and/or Bluetooth) to obtain the heating system 100 related information (e.g., alters, real-time monitoring information, data log, etc.) from the master heater 126 and/or to program operation and maintenance schedules of the heating system 100. The heating system 100 includes a connection port 132 configured to connect with a user equipment connection cable 302 which enables custom programming and setup of the heating system 100. The heating system 100 includes a display and/or an indicator 138 (e.g., visual or sound displays) to communicate operational information, notifications, or alerts to users (e.g., heater failure, overheating, alerts, notice of failure heating elements 116, maintenance schedule and reminders, etc.). The display and/or indicator 138 may include a graphical user interface (GUI) to enable and manage user interaction with the heating system 100.

[0029] FIGS. 2A and 2B show perspective front and rear views of an example heating system 100, respectively. In the illustrated example, the heating system 100 includes three heaters 106 each including the heating element 116, the sensor 118, and the control unit 120 (e.g., the control unit 120 of the heater 106 that is connected to the smart probe 108 is the master control unit 121). The heating element 116 may be any suitable heating element, such as heating plates, heating tubes, electric immersion heaters, protector tubes (P tubes), etc. The wattage of the heating elements 116 may be between about 3000-36000 Watts. The sensor 118 may be any suitable temperature sensor to measure a temperature of the liquid 102, such as a thermal couple, metal probe sensor, ultrasonic sensor, infrared sensor, capacitance sensor, etc. The sensor 118 is configured to measure a temperature of the liquid 102 that is about -40 degrees Celsius (°C) to 300 °C.

[0030] The heating system 100 includes multiple heater safety shutdown mechanisms/protocols. For example, each control unit 120 of each heater 106 is configured to perform multiple heater safety shutdown mechanisms/protocols. For heater safety, UL (Underwriter Laboratories) listed thermal-cut-off (TOC) switches are in each heating elements 116 so that if the TCO senses temperature that is too hot (e.g., above a pre-determined temperature), it will open or cutout, resulting in the heating element 116 no longer heating. Also for heater safety, system-on-chip (SOC) thermocouples (TC), such as K-type TCs, monitoring each heating elements 116. The heater safety shutdown mechanisms/protocols enable the heaters 106 to autoreset and auto-shutdown or de-energize the heating elements 116 if overheating occurs. [0031] The heating system 100 includes an enclosure 200 configured to enclose, seal, or protect the electrical components of the heating system 100 from the ambient environment (e.g., an outdoor or indoor environment). Specifically, the control unit 120 is enclosed by the enclosure 200. The enclosure may be a NEMA 3R rated enclosure (e.g., rated for housing power distribution, lighting contractors, switch gear, and other electrical components that need to be protected in an outdoor environment) with improved sealing of a top cover 202.

[0032] The heating system 100 includes a power entry 204 through the enclosure 200. The power entry 204 is configured to allow the heating system 100 to connect to the power cable/wire 112. The power cable/wire 112 and the power entry 204 may be configured to be compatible with a power supply of 240 volts to 480 volts.

[0033] The heating system 100 includes the display and/or indicator 138 (e.g., visual or sound displays) to communicate operational information, notifications, or alerts to users (e.g., heater failure, overheating, alerts, notice of failure heating elements 116, maintenance schedule and reminders, etc.). For example, the heating system 100 includes an organic light-emitting diode (OLED) display 206 and LED indicators 208. The display 206 may be a GUI to enable and manage user interaction with the heating system 100. For example, the display 206 (e.g., GUI) may display operational conditions (e.g., liquid temperature, tank temperature, liquid level, sensor connected, time, heater status, etc.) and enable users to set and change the operational conditions. The LED indicators 208 may be any colors, such as, but not limited to, red and blue LEDs. The LED indicators 208 may be configured to be 360 degrees viewable. The LED indicators 208 may be sealed (e.g., NEMA 3R rated sealing).

[0034] The heating system 100 includes the connection port 132 configured to connect with a user equipment connection cable which enables custom programing and setup of the heating system 100. The connection port 132 may be a 1 -pin connector and with a NEMA 3R rated twist lock. FIG. 3 shows an example of a 16-pin connector 300 allowing connection between the user equipment connection cable 302 (e g., customer wiring) and a system wiring 304 to enable certain freedom for custom programming and setup of the heating system 100. The user equipment connection cable 302 may be wired with the system wiring 304 to have multiple relays 306. Each of the pins can be used as auxiliary connection points to the control unit 120. [0035] As an example, one of the pins can be connected to a relay for the fill valve 103 and another pin can be connected to a relay for the drain valve 105 (e.g., the control units 120 are programmed to recognize the fill valve 103 and the drain valve 105). For example, the control units 120 may be programmed to operate the heating system 100 such that if a user choses to connect the fill valve output to an actual valve (e.g., the fill valve 103), when the smart probe 108 detects that liquid level is too low (e.g., below a pre-determined liquid level), the heating system 100 would automatically refill the liquid 102 to a desired liquid level (e.g., the control unit 120 would send control signals to open the fill valve 103 and refill the liquid 102 into the tank 104). For example, the control units 120 may be programmed to operate the heating system 100 such that if the user choses to connect the drain valve output to an actual valve (e.g., the drain valve 105), when the smart probe 108 detects that liquid level is too high (e.g., above a pre-determined liquid level), the heating system 100 would automatically drain the tank 104 to a desired liquid level. The heating system 100 can also be configured such that a notification of liquid level is sent to a user via an email, and the user can use the html pages to operate the fill valve 103 or operate the drain valve 105 to adjust the liquid level.

[0036] There are at least two extra relay outputs that a user can program (e.g., on html pages). A user can define rules/conditions for programming the extra relay outputs. For example, a user can define one of the rules/conditions to turn on the relay when the heater 106 is operating and the relay is connected to a bubbler or stirrer so that when the heater 106 is turned on the bubbler or stirrer is also turned on to agitate the liquid 102.

[0037] The connection port 132 and the system wiring 304 are configured for RS485 wired connection, which can be connected to an existing programmable logic controller (PLC) system such that a user can get information and/or provide instructions or data to the control units 120. In addition, in certain aspects, users can receive the heating system 100 related information (e.g., alerts, real-time monitoring information, process data log, heater failure, overheating, notice of failed heating elements 116, maintenance schedule and reminder, etc.) using wired only connection (e.g., the RS485 wired connection) instead of via emails. [0038] The heating system 100 includes a data connection port 210 configured to allow connection with the smart probe 108 to receive data from the smart probe 108. The data connection port 210 may be a 6-pin connector and with a NEMA 3R rated twist lock.

[0039] The control units 120 (e.g., one control unit 120 for each of the heaters 106) are enclosed by the enclosure 200. Each of the control units 120 includes necessary electrical components and circuitry (e.g., processor, memory, computer, WiFi receiver and transmitter, etc.). For example, the control unit 120 can include a high-performance wireless system-on-chip (SOC) central processing unit (CPU), a high gain power amplifier (e.g., PA +26dBm), and is WiFi enabled (e.g., ISM 2.4 GHz WiFi, 802.11 b/g/n). Additionally, each of the control units 120 includes an odometer or a timer to monitor heater life and includes an hour meter and a cycle counter for advanced maintenance operations.

[0040] The control units 120 are in communication with the various components of the heating system 100 to enable features including: liquid temperature sensing, auto-reconnect WiFi, self-diagnostics of safety systems, user programmable outputs, (7) programmable schedules H/M/D, tamper-proof TCO (P) safety circuit, self-resetting TCO safety thermal fuses, redundant heat safety arrangement, notifications to users (e.g., via the display and/or indicator 138, email, html page, wired connection, the connection port 132), autonomous operation, manual override, auto-fill tank level system, auto-drain for overfill condition, advanced maintenance, etc.

[0041] Examples 1-4 are provided to illustrate some features of the heating system 100. As may be appreciated, the heating system 100, especially the control units 120, are configured to perform steps/features disclosed in Examples 1-4.

[0042] Example 1 : Startup the heating system

[0043] The heating system 100 includes at least one emersion heater (such as one of the heaters 106) connected within an loT connected heater mesh work which allows autonomously control and built-in information exchange. The central master unit (e.g., the master heater 126) and secondary units (e.g., the secondary heaters 128) within the same tank/vat (e.g., the tank 104) having wireless radio communications for daily operations and safety monitoring. The central master unit (e.g., the master heater 126) may be configured to direct a user to start the heating system 100 using the display 206 (e g., a GUT). For example, as shown in FTG. 4, a series of startup screens 400 may be displayed on the display 206 to provide start-up directions to users. A screen 402 indicates the name of the heating system 100. A screen 404 indicates or prompts a user to power up the heating system 100 (e.g., connecting a power line or supply to the power entry 204). The power up status may be displayed along with software/firmware information of the heating system 100. A screen 406 indicates or prompts a user to setup/confirm a WiFi connection.

[0044] A screen 408 indicates or prompts a user to connect device(s). The device(s) to be connected may refer to the secondary heaters 128 (to be connected to the power cable/wire 112) and/or any other auxiliary devices/equipment of the heating system 100. Additional secondary heaters 128 can be added to the same tank 104 by the user. Secondary heaters 128 are wirelessly “meshed” with the master heater 126 while maintaining autonomous operations and independent self-diagnosis and safety systems which are not reliant on the master heater 126. The heating system 100 schedules are controlled from the master control unit 121 of the master heater 126 and data sharing is continuous throughout all units (e.g., the master and secondary heaters 126 and 128). In an event of a failure of the master heater 126, the secondary heater 128 will perform a safety shut down until the mesh network is re-established or a new master heater 126 is established. The device(s) 130 to be connected may also refer to a user device (e.g., any suitable smart device, such as a cell phone, a computer, a laptop, a tablet device, etc.) connecting to the heating system 100 through the wireless connection (e.g., via WiFi).

[0045] A screen 410 indicates or prompts a user to set operational parameters. The operational parameters may include any parameters or conditions required to ensure operation of the heating system 100, such as heating temperature, cycle, time, liquid level, maintenance schedule, etc. The operational parameters may be set via a user device connected to the heating system 100 or may be set using the display 206 (e.g., a GUI). Once the operational parameters have been set, the heating system 100 operates on itself and all “meshed” heaters (e.g., the master and secondary heaters 126 and 128) within the same tank 104 will operate automatically.

[0046] Once the heating system 100 is setup, the display 206 may show operational conditions and/or parameters. In FIG. 5, an operation screen 500 on the display 206 is shown as an example. The operation screen 500 is configured to display various operation conditions and parameters of the heating system 100, including but not limited to, live temperature 502 (of the liquid 102), mesh network indicator 504 (e.g., indicating presence of the meshed heaters), timer indicator 506 (e.g., indicating whether the odometer or the time is on), heater status 508 (e.g., ON/OFF indicator), liquid level graph 510, external level sensor selected 512 (e.g., any suitable external liquid level non-contact sensor, such as, but not limited to, a 24 VDC (volts, direct current) non-contact water level sensor), main unit IP address on WiFi 514, and setpoint 516 (e.g., desired temperature set point of the liquid 102 in the tank 104). The operation screen 500 may present a short summary of some important operation conditions and/or parameters. The operation screen may also be configured to only display an individual parameter per screen. An operation screen 518 for example only displays the tank temperature. The content and timing of display screen are configurable. The heating system 100 may be configured to alternate the content on the display 206 between the operation screen 500 (e.g., summary page) and the operation screen 518 (e.g., individual parameter). The alternation between different display pages (e.g., alternation between the operation screens 500 and 518) may be configurable and may be every few seconds (e.g., two seconds, three seconds, four seconds, etc.).

[0047] Example 2: Advanced monitoring with loT connectivity

[0048] The devices and components of the heating system 100 are in communication with on another such as being, for example, connected via an ToT network. No software or app is required for users to manage or receive data from the heating system 100. The control units 120 are configured to generate web pages for each of the heaters 106. All data and operational instructions are communicated through in-house communications via WiFi (e.g., through email push notifications) such that no data is uploaded to a cloud service. Self-generated html code web style GUI screens on connected user devices eliminate the need for downloaded software or device application to be maintained.

[0049] The heating system 100 is configured to provide real time data access to users. The operation data (e.g., operation conditions and/or parameters) measured by the smart probe 108 and/or the sensor 118 can be communicated to users in real-time. The heating system 100 is configured to provide operation data via user-selected methods. For example, a user during the heating system setup process may choose to receive communication via emails at specific time and/or intervals. The control unit 120 (the master control unit 121 ) of the master heater 126 of the heating system 100 is configured to email user notifications for troubleshooting in real-time (e.g., multiple user accesses and warnings). The control unit 120 (the master control unit 121) of the master heater 126 of the heating system 100 is configured to self-generate minute-by-minute data log file in html code, for example, that may be automatically provided or transmitted, via emails, to users daily or on demand at user selected time. The data log file and data monitored by the smart probe 108 can also be downloaded from the connection port 132 using the connection cable 302.

[0050] Example 3: Self-diagnostic and multilayered safety

[0051] The heating system 100 is configured to have added safety features that prevent the possibility of bypassing any safety features and help prevent heater failures/accidents due to dry tank conditions. More specifically, the advanced redundant safety features eliminate the possibility of operating in a dry tank, overheating or the bypassing of built-in safety systems though continuous electronic system self-diagnosis.

[0052] The heating system 100 has multiple layers of safety measures. One of the safety features includes that each the heating elements 116 is monitored by a UL recognized auto-reset TCO switch. The TCO switch is configured to open when the temperature of the heating element 116 is above a pre-determined temperature range. Another of the safety features includes the control unit 120 having a SOC to read at least one of the sensors 118 (e.g., K-type TCs) coupled to the heating elements 116. The SOC is configured (e.g., hardcoded) to shut down when the temperature reading at the sensor 118 is above a pre-determined value or range. If any of the TCOs or TCs reaches a thermal critical state, the heater 106 would shut down and not re-energize until a cool/down rest procedure is followed. The heater 106 may also be configured to shut down when the liquid level (detected by the smart probe 108) is below a pre-set level or range. These shutdowns are tamper-proof shutdowns that users will not be able to bypass or jumpstart the shutdown heaters 106 without resolving the issues (e.g., heater temperature above a critical level, liquid level below a critical level). Specifically, the heating elements 106 are coupled to TCO and TC switches through hack-proof firmware that cannot override safety rules (e.g., the heater temperature must be below a pre-determined temperature and/or the liquid level must be above a pre-determined level for the heating elements 1 16 to operate). The heaters 106 would not operate if any safety systems, naming the TCO, thermal TC protectors, and liquid level control, fails or is bypassed. When any of the safety systems fails, the heater 106 automatically shuts down or deenergizes the heating elements 116 to prevent overheating. The heating system 100 is also configured to notify users about the shutdown. For example, the heating system 100 is configured to send notifications through emails (on WiFi only), on the display 206, and/or through the indicators 208. In a heater shutdown event, the heating system 100 may send multiple emails, e.g., at last three emails, to the users.

[0053] FIG. 6 shows an example process 600 of safety procedures performed by the heating system 100. Steps in the process 600 is a computer-implemented process that is performed or coordinated by the control unit 120 (the master control unit 121). The process 600 includes confirming the presences of safety firmware, smart probe and sensors (step 602). For example, the control unit 120 (the master control unit 121) is configured to scan the heating system 100 to ensure the smart probe 108 and the safety firmware are connected before turning on the heating elements 116. The control unit 120 (the master control unit 121) may send signals to check that the smart probe 108 is properly connected to the master heater 126. The control unit 120 (the master control unit 121) may send signals to check that the heating elements 116 and the sensors 118 are properly configured, for example, the TCO switches and the TC protectors are properly installed.

[0054] In step 602, if the control unit 120 (the master control unit 121) detected that any of the safety firmware, the smart probe 108 and the sensors 118 were not properly connected or configured, it would send a notification to user(s) to prompt the user(s) to resolve the issue. The notification may include concise or detailed descriptions of the problems occurred and may include suggested procedures to resolve the issues. The notification may be sent through emails and/or displayed on the displayed 206.

[0055] The process 600 includes starting up heater operations once the safety procedure is confirmed (step 604).

[0056] The process 600 includes monitoring violation of safety criteria and shutdown one or more heaters if any of the safety criteria is violated (step 606). The safety criteria include the multiple layers of safety measures that lead to automatic heater shutdown (e.g., the TCO, TC protectors, and/or the liquid level control fail or bypassed). The safety criteria may also include shutdown conditions including over temperature (e.g., detected by the sensors 118 and/or the smart probe 108), low liquid level (e.g., detected by the smart probe 108), VOC level overed a predetermined value or range (e.g., detected by the smart probe 108), pH level out of a pre-determined range (e.g., detected by the smart probe 108), chemical detection or concentration out of a predetermined range (e.g., detected by the smart probe 108). The heater 106 is shutdown if overtemperature is detected. In some embodiments, only one of the heaters 106 or only few of the heaters 106 are overheated, and in these cases, only the overheated heaters 106 are shutdown and other heaters 106 remain in operation. In some embodiments, all of the heaters 106 are shutdown, in cases that the liquid level is too low, VOC, CO, or CO2 concentration out of range, violation of safety criteria in step 602 (e.g., the safety firmware, smart probe and sensors tampered), or any other conditions specified by the user.

[0057] The process 600 includes sending notifications to users about the safety criteria violation (step 608). The notification may include concise or detailed descriptions of the violations and may include suggested procedures to resolve the violations. The notifications may be sent through emails and/or displayed on the displayed 206. For example, if one of the heaters 106 is shut down due to overtemperature (other heaters 106 still in operation), the user may be notified with specific heater information and reasons for the shutdown and may be instructed to turn off and turn on (e.g., cycle power) the heater when the heater is cooled to normal operation temperature. In some embodiments, the control unit 120 (the master control unit 121) may determine that the safety violation would require an on-site visit of a technician or engineer, and this can be communicated and/or scheduled through the notification.

[0058] The process 600 includes starting the heater operation once the safety criteria violation is resolved (step 610).

[0059] FIG. 7 shows an example notification to the user about safety shutdown (e.g., in step 608). In the illustrated example, the heating system 100 in an event of thermal shutdown due to high heater temperature displays screens 700, 702, and 706 on the display 206. The thermal shutdown may be triggered if any TCOs trip or if any of the sensors 118 (e.g., TCs) detects a temperature higher than a pre-determined value. The screen 700 indicates “Warning Thermal Shutdown.” The screen 702 indicates “hot.” The screen 704 indicates “To Clear Cycle Power.” The screens 700, 702, and 704 are only illustrated as an example. Other messages, to the extent of indicating warning and/or providing instructions to reset or resolve the issues, can also be shown on the display 206. The screens 700, 702, and 704 may be cycled through until the problematic heater is reset or the issue resolved.

[0060] Example 4: Autonomous operation and advanced maintenance

[0061] The heating system 100 is also configured to enable autonomous operations and advanced maintenance. With the control units 120 in communication with each other, a user can set a variety of control functions using the control unit 120 (e.g., input instructions using the display 206) and/or using a smart device connected to the heating system 100. For example, a user can set the heating temperature per schedule (e.g., daily schedule, weekly schedule, etc.). A user can set On/Off schedule for the heaters 106.

[0062] Through the built-in programmable auxiliary control outputs of the connector 300, user equipment/devices can be connected to and operated by the heating system 100 autonomously once programmed. For example, the control unit 120 (the master control unit 121) and the auxiliary control outputs of the connector 300 may be programmed to indicate and/or refdl the liquid 102 through the fdl valve 103 when the liquid level is determined to be below a predetermined level. As shown in FIG. 8, the display 206 may show a tank fill screen 800 indicating “Caution Fill Tank” to prompt a user to add the liquid 102 to the tank 104. Simultaneously or alternatively, the heating system 100 may automatically control the fill valve 103 to fill the tank 104 upon determination of a low liquid level (e.g., below a pre-determined liquid level).

[0063] As another example, the control unit 120 (the master control unit 121) and the auxiliary control outputs of the connector 300 may be programmed to indicate and/or drain the tank 104 through the drain valve 105 when the liquid level is determined to be above a predetermined level. As shown in FIG. 8, the display 206 may show a drain cycle screen 802 indicating “Caution Drain Cycle” to prompt a user to drain the liquid 102 from the tank 104. Simultaneously or alternatively, the heating system 100 (the master control unit 121) may automatically control the drain valve 105 to drain the tank 104 upon determination of a high liquid level (e g , above a pre-determined liquid level). The pre-determined liquid levels to drain and to refdl the tank 104 may be programmed using the control unit 120 (the master control unit 121) and/or using a smart device connected to the control unit 120 (the master control unit 121).

[0064] The auxiliary control outputs of the connector 300 include at least two additional relay outputs which can be defined by a user.

[0065] The control unit 120 includes an odometer and/or a timer to keep track of operation time of the heaters 106. The control unit 120 may be configured to monitor the heater life and maintenance schedule using the tracking records of the odometer of timer. The control unit 120 (the master control unit 121) may be configured to set maintenance schedule and send reminders to users through emails and/or using the display 206.

[0066] This written description describes the invention so as to enable a person of ordinary skill in the art to make and use the disclosed technology, by presenting examples of the elements recited in the claims. The detailed descriptions of those examples are non-limiting.