Smart Autotune Thermostat for Home Assistant (Marketplace integration)

Installs: 60 sharing analytics
GitHub stars: 256
Connection: Works locally
Upkeep: No update in 6 to 18 months
Version: 4.2.1, March 18, 2026
Category: Climate, Thermostats and heating
Kind: Marketplace integration
Needs: Needs the Marketplace (HACS on 2026.10 and older)
Domain: sat
Source: github.com/Alexwijn/SAT
Issues: Report an issue

Independent directory, made by the developer of Vulpo. Not affiliated with Home Assistant or the Open Home Foundation.

Screenshots From the README of Alexwijn/SAT.

About

Smart Autotune Thermostat is a custom integration that controls a boiler through compatible gateways using a PID algorithm. It works with OpenTherm gateways over MQTT or serial, as well as EMS-ESP gateways, and can also run as a PID on/off thermostat. It adds climate, sensor, number and binary sensor entities, and it communicates locally. Automatic gain tuning and adjustable heating curve coefficients let it work out a boiler setpoint with outside temperature compensation. Other features include multi-room control, presets such as away, sleep, home and comfort, overshoot protection, pulse width modulation, and open window detection through contact sensors. Setup runs through the Home Assistant interface, and the integration can be discovered on the network.

Automatic summary of the README and code of Alexwijn/SAT. Something wrong, or are you the maintainer and want your own text here? Get in touch

Supports

Works locally Talks to your devices on your own network. No vendor cloud in between.
Found by itself Home Assistant spots it on the network and offers to add it.
From the Marketplace Installed through the Marketplace, formerly HACS.

Provides

Climate
Sensors

Setting it up

Install it from the Marketplace and restart Home Assistant, then add it under Settings, Devices and services.

Areas

Thermostat
Radiators
Rooms

Automatic Gains

Automatic Gains (recommended)

Heating System

System

MQTT Configuration

Mode

OpenTherm Gateway Setup

Name
MQTT Topic
Device ID

EMS-ESP Gateway Setup

Name
MQTT Topic

Overshoot Protection

Value

Configure the PID controller manually.

Derivative (kD)
Integral (kI)
Proportional (kP)

After setup

Enable error monitoring
Climate valve offsetOffset to adjust the opening degree of the climate valve.
Dynamic Minimum Setpoint (Experimental)Activates the dynamic setpoint adjustment based on the boiler's return temperature, which also helps identify if any valves are closed.
Force Pulse Width Modulation
Maximum ConsumptionThe maximum gas consumption when the boiler is active.
Maximum Relative ModulationRepresenting the highest modulation level for an efficient heating system.
Minimum ConsumptionThe minimum gas consumption when the boiler is active.
Sample TimeThe minimum time interval between updates to the PID controller.
Simulation
Target Temperature StepAdjust the target temperature step for fine-tuning comfort levels.
Thermal ComfortEnable the use of the Simmer Index for thermal comfort adjustment.
Automatic Gains ValueThe value used for automatic gains in the PID controller.
Derivative (kD)The derivative term (kD) in the PID controller, responsible for mitigating overshooting.
Derivative Time WeightA parameter to adjust the influence of the derivative term over time, particularly useful for reducing undershoot during the warm-up phase when the heating curve coefficient is correctly set.
Maximum Duty Cycle for Pulse Width ModulationThe maximum duty cycle for Pulse Width Modulation (PWM), controlling the boiler's on-off cycles.
Heating Curve CoefficientThe coefficient used to adjust the heating curve.
Heating Curve Version
Integral (kI)The integral term (kI) in the PID controller, responsible for reducing steady-state error.
Maximum SetpointThe optimal temperature for efficient boiler operation.
Minimum Setpoint Controller Version
PID Controller Version
Proportional (kP)The proportional term (kP) in the PID controller, responsible for the immediate response to errors.
Contact SensorsContact Sensors that trigger the system to react when a window or door is open for a period of time.
Heating Mode
Activity Temperature
Away Temperature
Comfort Temperature
Home Temperature
Sleep Temperature
Synchronize with thermostat attached to the boiler
Synchronize climates with preset (sleep / away / activity)
Duty Cycles per hourThe maximum amount of duty cycles per hour.
Automatic duty cycleEnable or disable automatic duty cycle for Pulse Width Modulation (PWM).
Synchronize climates with mode
Overshoot Protection (with PWM)Enable overshoot protection with Pulse Width Modulation (PWM) to prevent boiler temperature overshooting.
Temperature Sensor maximum value ageThe maximum age of the temperature sensor value before considering it as a stall.
Minimum time for window to be openThe minimum time a window must be open before the system reacts.

Texts from the code of Alexwijn/SAT.

Actions

Reset IntegralThis service resets the integrating part of the PID controller for the specified climate entity. This may be useful if the integral value has become too large or if the PID controller's performance has degraded.
Pulse Width ModulationForce enable or disable the Pulse Width Modulation, do note that it may be turned on or off automatically right after again.Fields: Enabled

From the README

Please:star: this repo if you find it useful.
Multi-room temperature control with support for temperature synchronization for main climates
Overshoot protection value automatic calculation mechanism
Adjustable heating curve coefficients to fine-tune your heating system
Target temperature step for adjusting the temperature in smaller increments
Presets for different modes such as Away, Sleep, Home, Comfort
Automatic gains for PID control
PWM and Automatic-duty cycle
Overshoot protection to prevent the boiler from overshooting the setpoint ( Low-Load Control )
Climate valve offset to adjust the temperature reading for your climate valve
Sample time for PID control to fine-tune your system's response time
Open Window detection
Control DHW setpoint