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

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

    class Inputs{
        +initInputs()
        -initMeasurement()
        -updateAverage()
        -updatePrediction()
        -taskInput()
        -linearRegressionPredict()
        +getChamberTemperature()
        +getOutdoorTemperature()
        +getInletFlowTemperature()
        +getReturnFlowTemperature()
        +getBurnerError()
    }

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

    class Control{
        initControl()
        +taskControl()
        +getControlCurrentWeekday()
        -findControlCurrentTemperatureEntry()
        +getControlCurrentTemperatureEntry()
        -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 1
chamber_temperature 37.250000
chamber_temperature_avg10 37.237499
chamber_temperature_avg60 37.438541
chamber_temperature_damped 42.185040
chamber_temperature_pred60 36.638443
inlet_flow_temperature 35.625000
inlet_flow_temperature_avg10 35.618752
inlet_flow_temperature_avg60 35.415627
inlet_flow_temperature_damped 39.431259
inlet_flow_temperature_pred60 36.078678
outdoor_temperature 14.687500
outdoor_temperature_avg10 14.662500
outdoor_temperature_avg60 14.646875
outdoor_temperature_damped 9.169084
outdoor_temperature_pred60 14.660233
return_flow_temperature 39.937500
return_flow_temperature_avg10 40.087502
return_flow_temperature_avg60 41.146873
return_flow_temperature_damped 32.385151
return_flow_temperature_pred60 37.311958
chamber_temperature_state 0
outdoor_temperature_state 0
inlet_flow_temperature_state 0
return_flow_temperature_state 0
safety_state 0
control_state 3
control_current_weekday 5
control_current_entry_time 17100
control_current_entry_chamber_temperature 80.000000
control_current_entry_return_flow_temperature 30.000000
sntp_state 0
system_unixtime 1762012743
uptime_seconds 465229
wifi_rssi -72

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