Custom Controller for Thermal Energy Storage

I want to develop a custom electronic controller for a residential thermal energy storage water tank. The controller will manage a heat pump, three electric resistance heaters, temperature sensors, energy meters and communication with a cloud/app platform. Features: Microcontroller: ESP32 or equivalent industrial-grade MCU with Wi-Fi/Bluetooth Power Supply: 230VAC input with isolated AC/DC power supply for the control electronics Temperature Sensors: Minimum 10 temperature sensor inputs, including redundant sensors for Top / Middle / Bottom tank zones and outlet pipe temperature sensors Electric Heaters: Control of 3 independent resistance heaters, normally 5kW each, assigned to L1 / L2 / L3 phases Heater Switching: 3 SSR control outputs with provision for external SSRs and a master safety contactor Heat Pump Control: 2 configurable potential-free relay outputs for Heat Pump Enable/Stop or SG-Ready interface Communication: Wi-Fi for cloud/app connectivity and OTA firmware updates Bluetooth for commissioning/setup RS-485 / Modbus interface for heat pump communication, diagnostics and future expansion Provision for communication with external wireless energy meters Energy Monitoring: Interface with 3-phase main-grid energy meter Heat-pump energy meter Resistance-heater energy meter System should use import/export power information to control heaters according to available solar surplus Safety: Independent master contactor output Over-temperature protection Watchdog protection Contactor feedback input Safe shutdown if communication or sensor faults occur All heaters and heat pump OFF after power failure, followed by configurable restart delay Additional I/O: Digital inputs for alarms / feedback Outputs for optional circulation pump Expansion capability for additional tanks or future accessories Programming / Reprogramming: OTA firmware updates through Wi-Fi plus USB/UART programming/debug interface. PCB Design: Preferably designed in KiCad. PCB should be suitable for reliable long-term residential installation and designed with proper isolation between 230VAC, relay/contactor circuits and low-voltage electronics. Deliverables: Complete schematic and PCB design files, source files, BOM, Gerber/manufacturing files, firmware-ready prototype PCB, and at least one assembled and debugged sample.