--- title: "Smart Autotune Thermostat" description: "Smart Autotune Thermostat is a Marketplace integration for Home Assistant. It has 60 installs sharing analytics, works locally and was last updated March 18, 2026." canonical: "https://vulpo.app/integrations/marketplace/alexwijn-sat" url: "https://vulpo.app/integrations/marketplace/alexwijn-sat.md" last-updated: "2026-10-22" version: "1.4" --- # Smart Autotune Thermostat > Smart Autotune Thermostat is a Marketplace integration for Home Assistant. It has 60 installs sharing analytics, works locally and was last updated March 18, 2026. 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](https://vulpo.app/contact) [Open in My Home Assistant](https://my.home-assistant.io/redirect/hacs_repository/?owner=Alexwijn&repository=SAT&category=integration) On Home Assistant 2026.11 or newer? [Open it in the Marketplace](https://my.home-assistant.io/redirect/marketplace_repository/?owner=Alexwijn&repository=SAT&category=integration) ## 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. ## 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 offset**: Offset 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 Consumption**: The maximum gas consumption when the boiler is active. - **Maximum Relative Modulation**: Representing the highest modulation level for an efficient heating system. - **Minimum Consumption**: The minimum gas consumption when the boiler is active. - **Sample Time**: The minimum time interval between updates to the PID controller. - **Simulation** - **Target Temperature Step**: Adjust the target temperature step for fine-tuning comfort levels. - **Thermal Comfort**: Enable the use of the Simmer Index for thermal comfort adjustment. - **Automatic Gains Value**: The 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 Weight**: A 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 Modulation**: The maximum duty cycle for Pulse Width Modulation (PWM), controlling the boiler's on-off cycles. - **Heating Curve Coefficient**: The 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 Setpoint**: The 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 Sensors**: Contact 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 hour**: The maximum amount of duty cycles per hour. - **Automatic duty cycle**: Enable 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 age**: The maximum age of the temperature sensor value before considering it as a stall. - **Minimum time for window to be open**: The minimum time a window must be open before the system reacts. Texts from the code of [Alexwijn/SAT](https://github.com/Alexwijn/SAT). ## Actions - **Reset Integral**: This 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 Modulation**: Force 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 From the README of [Alexwijn/SAT](https://github.com/Alexwijn/SAT#readme), [GNU GPL v3.0](https://spdx.org/licenses/GPL-3.0.html). Shortened. ## At a glance - Kind: Marketplace integration - Category: [Climate](https://vulpo.app/integrations/category/climate.md), Thermostats and heating - Number: 60 installs sharing analytics; 256 GitHub stars - Connection: Works locally - Upkeep: No update in 6 to 18 months - Needs: Needs the Marketplace (HACS on 2026.10 and older) - Latest version: 4.2.1, last updated March 18, 2026 - Domain: `sat` - Source: - Issues: - Screenshot: https://vulpo.app/integrations-img/88125fb67ac685f0.webp (from Alexwijn/SAT's README) - Screenshot: https://vulpo.app/integrations-img/c924865a4a04febc.webp (from Alexwijn/SAT's README) In Vulpo: Climate card, Chart card, Apple Watch, Climate Live Activity (Pro) [Widgets & Live Activities in Vulpo](https://vulpo.app/features/widgets-and-live-activities) Independent directory, made by the developer of Vulpo. Not affiliated with Home Assistant or the Open Home Foundation. [About these numbers](https://vulpo.app/integrations/about) Last updated 2026-10-22. Source: https://vulpo.app/integrations/marketplace/alexwijn-sat --- - HTML version of this page: https://vulpo.app/integrations/marketplace/alexwijn-sat - Site index for agents: https://vulpo.app/llms.txt - Everything in one document: https://vulpo.app/llms-full.txt - All pages: https://vulpo.app/sitemap.xml