smart-oil-heating-control-system

Software

Design

classDiagram
Inputs <|-- Control
Outputs <|-- Control
Sntp <|-- Control
Inputs <|-- Safety
Outputs <|--|> Safety

Inputs <|-- Metrics
Outputs <|-- Metrics
Control <|-- Metrics
Safety <|-- Metrics
Sntp <|-- Metrics

    class Inputs{
        +initInputs()
        -taskInput()
        +getChamberTemperature()
        +getOutdoorTemperature()
        +getInletFlowTemperature()
        +getReturnFlowTemperature()
        +getBurnerError()
    }

    class Outputs{
        +initOutputs()
        +getCirculationPumpState()
        +setCirculationPumpState()
        +getBurnerState()
        +setBurnerState()
        +getSafetyControlState()
        +setSafetyControlState()
    }

    class Control{
        +taskControl()
        -controlTable
        +getControlState()
    }

    class Safety{
        +initSafety()
        -taskSafety()
        -setSafeState()
        -checkSensorSanity()
        +getSensorSanityStates()
        +getSafetyState()
    }


    class Wifi{
        +initWifi()
    }

    class Sntp{
        +initSntp()
        +getSntpState()
    }

    class Metrics{
        +initMetrics()
        -taskMetrics()
        -metrics
        +event_handler()
        +connect_wifi()
        +setMetrics()
    }

Prometheus Metrics

curl http://X.X.X.X:9100/metrics

Example

burner_fault_pending 1
circulation_pump_enabled 1
burner_enabled 0
safety_contact_enabled 0
chamber_temperature 58.750000
chamber_temperature_avg10 58.931252
chamber_temperature_avg60 59.190475
chamber_temperature_pred60 55.870998
inlet_flow_temperature 53.875000
inlet_flow_temperature_avg10 53.900002
inlet_flow_temperature_avg60 53.994320
inlet_flow_temperature_pred60 52.848743
outdoor_temperature 18.000000
outdoor_temperature_avg10 18.006250
outdoor_temperature_avg60 18.002840
outdoor_temperature_pred60 18.050785
return_flow_temperature 48.625000
return_flow_temperature_avg10 48.718750
return_flow_temperature_avg60 48.846592
return_flow_temperature_pred60 47.383083
chamber_temperature_state 0
outdoor_temperature_state 0
inlet_flow_temperature_state 0
return_flow_temperature_state 0
safety_state 0
control_state 3
sntp_state 0
system_unixtime 1735242392
uptime_seconds 40
wifi_rssi -74

Status Encoding

Digital Themperatur Sensor DS10B20

• chamber_temperature_state
• outdoor_temperature_state
• inlet_flow_temperature_state
• return_flow_temperature_state

Enum eSensorErrorState in safety.h	Value	Description
SENSOR_NO_ERROR	0
SENSOR_TOO_HIGH	1	Sanity check failed
SENSOR_TOO_LOW	2	Sanity check failed
SENSOR_UNCHANGED	3	Sanity check failed
SENSOR_NOT_FOUND	4	No Communication

Safety Loop

• safety_state

Enum eSafetyState in safety.h	Value	Description
SAFETY_NO_ERROR	0
SAFETY_SENSOR_ERROR	1	At least one sensor failed
SAFETY_INTERNAL_ERROR	2	Internal error

Control Loop

• control_state

Enum eControlState in control.h	Value	Description
CONTROL_STARTING	0
CONTROL_HEATING	1	Burner running
CONTROL_OUTDOOR_TOO_WARM	2	Heating not needed
CONTROL_RETURN_FLOW_TOO_WARM	3	Heating not needed
CONTROL_FAULT_BURNER	4	Burner reported fault after threshold is reached
CONTROL_FAULT_SAFETY	5	Unable to control due safety fault
CONTROL_FAULT_SNTP	6	Unable to control due SNTP fault

SNTP Client

• sntp_state

Enum eSntpState in sntp.h	Value	Description
SYNC_SUCCESSFUL	0
SYNC_NOT_STARTED	1
SYNC_FAILED	2

Hardware

Function	ESP32	PLC ES32C14
Output CirculationPump	IO27	Relay 1 NC1
Output Burner Fire Signal	IO14	Relay 2 NC2
Output Safety Contact (powers Burner)	IO12	Relay 3 NC2
Input Burner Fault	IO19	Digital Input IN1
Input Temperature DS10B20	IO04	1-Wire