# HestiaPi ONE (Silent) > Open-source smart thermostat based on Raspberry Pi Zero W with 3.5\" touchscreen, BME280 sensor, and silent solid-state relays. Fully local control with no cloud dependency, MQTT support, and Home Assistant compatibility. ## Quick Facts - **Brand:** HestiaPi - **Board Type:** smart-thermostat - **Price:** ~$149.99 - **Product Readiness:** consumer - **CPU:** BCM2835 ARM1176JZF-S @ 1GHz - **CPU Architecture:** ARM11 - **RAM:** 512MB - **Flash:** microSD (pre-flashed) - **USB:** Micro-USB - **Power:** 24V AC - **Operating Voltage:** 3.3V - **SD Card:** microSD - **Display:** 3.5" TFT LCD with resistive touch 480×320 ## Connectivity - **Wifi:** 802.11 b/g/n - **Bluetooth:** Bluetooth 4.1 ## Open Source - **Status:** fully-open - **Firmware:** Yes - **Schematics:** Yes - **PCB Layout:** Yes - **License:** GPL-3.0 ## Compatible Firmware openhab ## Use Cases - smart-thermostat - hvac-control - smart-home - home-automation - environmental-monitoring - iot ## Components - **Raspberry Pi Zero W** (sbc): Broadcom BCM2835 SoC with 512MB RAM, WiFi 802.11 b/g/n, and Bluetooth 4.1 BLE single-board computer providing the main computing platform. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fdatasheets.raspberrypi.com%2Frpizero%2Fraspberry-pi-zero-w-reduced-schematics.pdf&ref=openhardware.directory&product=hestiapi-one-silent&source=md-export) - **BME280** (environmental-sensor): Combined digital temperature, humidity, and barometric pressure sensor connected via I2C at address 0x76. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.bosch-sensortec.com%2Fmedia%2Fboschsensortec%2Fdownloads%2Fdatasheets%2Fbst-bme280-ds002.pdf&ref=openhardware.directory&product=hestiapi-one-silent&source=md-export) - **AQG22205** (relay): Solid-state relay rated for 24V AC at 2A with zero-crossing switching for silent, click-free HVAC load control. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Findustrial.panasonic.com%2Fcdbs%2Fwww-data%2Fpdf%2FDSA0001%2FDSA0001COL14.pdf&ref=openhardware.directory&product=hestiapi-one-silent&source=md-export) - **HLK-PM01** (ac-dc-converter): AC-DC power module converting 100-240V AC to 5V DC at 600mA for direct HVAC-powered operation. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fdatasheet.lcsc.com%2Flcsc%2F2209151801_HI-LINK-HLK-PM01_C209907.pdf&ref=openhardware.directory&product=hestiapi-one-silent&source=md-export) - **XPT2046** (touch-controller): 4-wire resistive touchscreen controller with SPI interface and 12-bit ADC for the 3.5-inch touch display. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fdatasheetspdf.com%2Fpdf-file%2F746665%2FSHENZHENXPTEK%2FXPT2046%2F1&ref=openhardware.directory&product=hestiapi-one-silent&source=md-export) ## Protocols - **SPI** - **I2C** - **GPIO** ## GPIO Map | Pin | Name | Type | Functions | |-----|------|------|-----------| | GPIO02 | I2C SDA (BME280 sensor) | — | — | | GPIO03 | I2C SCL (BME280 sensor) | — | — | | GPIO12 | Relay 1 control | — | — | | GPIO23 | Relay 2 control | — | — | | GPIO18 | Relay 3 control | — | — | | GPIO16 | Relay 4 control | — | — | | GPIO11 | Touch panel IRQ | — | — | | GPIO24 | LCD chip select | — | — | | GPIO26 | Touch panel chip select | — | — | | GPIO22 | LCD reset | — | — | ## Available Software - **[openHAB](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2FHestiaPi%2Fhestia-touch-openhab&ref=openhardware.directory&product=hestiapi-one-silent&source=md-export)**: Official HestiaPi firmware based on openHAB home automation platform with touchscreen UI - **[Home Assistant (via MQTT)](https://openhardware.directory/r?to=https%3A%2F%2Fwww.home-assistant.io%2Fintegrations%2Fmqtt%2F&ref=openhardware.directory&product=hestiapi-one-silent&source=md-export)**: Integration with Home Assistant through MQTT protocol for remote monitoring and control ## Description ## Overview The HestiaPi ONE (Silent) is a fully open-source smart thermostat built around a Raspberry Pi Zero W (or Zero 2 W) and a custom PCB. It gives homeowners complete control over their heating, ventilation, and air conditioning systems without relying on any cloud service or surrendering personal data to third parties. The 3.5-inch resistive touchscreen provides an intuitive local interface, while WiFi connectivity enables remote access through a smartphone or web browser running the openHAB home automation platform. What sets the Silent variant apart is its use of Panasonic AQG22205 solid-state relays instead of traditional mechanical relays. These SSRs switch loads with zero audible click, making the thermostat suitable for bedrooms and quiet living spaces. The unit supports 3 to 5 relay configurations for single-stage through three-stage HVAC systems, covering standard US 5-wire 24V AC setups as well as European 240V AC installations. Both the hardware and software are released under the GPL-3.0 license, with KiCad PCB design files, Gerber manufacturing files, and the complete openHAB-based firmware available on GitHub. The onboard Bosch BME280 sensor measures temperature, humidity, and barometric pressure over I2C, while a Hi-Link HLK-PM01 AC-DC converter allows the thermostat to draw power directly from the HVAC common wire. For users without a C-wire, a 5V Micro-USB external power supply can be used instead. The device ships fully assembled in a 3D-printed case (black or white) with a pre-flashed SD card, ready for wall mounting. ## Where to Buy - [Tindie](https://openhardware.directory/r?to=https%3A%2F%2Fwww.tindie.com%2Fproducts%2Feternalsunshine%2Fhestiapi-one-silent%2F&ref=openhardware.directory&product=hestiapi-one-silent&source=md-export) — $149.99 ## Resources - [product](https://openhardware.directory/r?to=https%3A%2F%2Fwww.hestiapi.com&ref=openhardware.directory&product=hestiapi-one-silent&source=md-export) - [github](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2FHestiaPi%2Fhestia-touch-openhab&ref=openhardware.directory&product=hestiapi-one-silent&source=md-export) - [wiki](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2FHestiaPi%2Fhestia-touch-openhab%2Fwiki&ref=openhardware.directory&product=hestiapi-one-silent&source=md-export) - [schematics](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2FHestiaPi%2Fhestia-touch-pcb-dev&ref=openhardware.directory&product=hestiapi-one-silent&source=md-export) ## Tags `open-source`, `smart-thermostat`, `raspberry-pi`, `hvac`, `home-automation`, `privacy`, `local-control`, `mqtt`, `openhab`, `home-assistant`, `solid-state-relay`, `bme280`, `touchscreen` ## Images ![HestiaPi ONE (Silent)](https://nbg1.your-objectstorage.com/openhardware-directory/entities/hestiapi-one-silent/b4cd9b68b797.jpg) ![HestiaPi ONE (Silent)](https://nbg1.your-objectstorage.com/openhardware-directory/entities/hestiapi-one-silent/f6539c7b5e7f.jpg) ![HestiaPi ONE (Silent)](https://nbg1.your-objectstorage.com/openhardware-directory/entities/hestiapi-one-silent/e8b0b3e3034a.jpg) --- [View full device page](https://openhardware.directory/devices/hestiapi-one-silent)