ESP32 freeze kit parts list

Buy an ESP32 and waterproof DS18B20 that match ProbeHarbor’s push-ingest sketches. Adafruit and Amazon product pages, not a branded drop-ship kit.

Top view of a blue Arduino Uno microcontroller board on a white background
Arduino-compatible boards run the sketch that polls probes and publishes JSON. Photo: Wikimedia Commons contributor. CC0

ProbeHarbor does not sell hardware. Buy the parts below, then install the firmware from your browser with the web flasher: no Arduino IDE, no code, and it sends the board your Wi‑Fi and device key over the same USB cable. If you'd rather read or edit the code, the sketches under ds18b20_ingest expect an ESP32 with Wi‑Fi and a waterproof DS18B20. Buy the parts below (Adafruit for known SKUs, Amazon product links when you want a cheaper DevKit), then create a push device and flash a pre-filled sketch from Dashboard → Devices instead.

Recommended freeze BOM

Parts for an ESP32 freeze probe
Part Why Buy
ESP32 board HTTPS push ingest over Wi‑Fi (TLS on-chip) Adafruit ESP32-S3 Feather · HUZZAH32 · Amazon DevKit
Waterproof DS18B20 Pipe / crawlspace probe; works below freezing Adafruit #381 (includes 4.7 kΩ) · Amazon probe
4.7 kΩ pull-up Required on the 1-Wire data line if the probe pack does not include one Amazon 4.7k
USB power Wall wart or USB-C cable; keep the board warmer than the probe bay when you can Any 5 V USB supply rated ≥500 mA

Product listings rotate: treat Adafruit as the reference BOM. Amazon /dp/ links in bomLinks are Associates-friendly alternatives when a listing is still live. Generic “ESP32 + DS18B20 kit” bundles often ship DHT11 instead of a waterproof probe — skip those.

Wire it

Wiring diagram: ESP32 DevKit to waterproof DS18B20 with 4.7 kilohm pull-up on GPIO 4
Red → 3.3 V, black → GND, yellow/white data → GPIO 4, with a 4.7 kΩ pull-up between data and 3.3 V. The sample ingest sketch defaults to GPIO 4.
  • Red (VCC) → ESP32 3.3 V
  • Black (GND) → GND
  • Yellow / white (data) → GPIO 4 (sample sketch default; any free digital GPIO works if you change the pin)
  • 4.7 kΩ between data and 3.3 V

Strap the stainless probe to the coldest pipe or north wall with a cable tie, then wrap foam insulation over probe + a short pipe segment so you read pipe temperature, not room air.

Flash and connect

  1. Create a free account and a push device on Devices.
  2. Open the web flasher in Chrome or Edge, plug in the ESP32, click Install, then send your Wi‑Fi and device key. It reports "First reading delivered" when the probe is live.
  3. Prefer code? Download the pre-filled Arduino .ino or MicroPython .py from Devices and flash it per ESP32 flashing options (Serial 115200 should show POST 200).
  4. Optional: print the ingest kit QR on the enclosure.
  5. Set freeze threshold + email under Alerts → Essentials and enable time-to-freeze remaining-hours if you want a clock before the probe crosses freeze.

What not to buy for pipe freeze

  • DHT11-only starter kits: weak below freezing; short leads; not waterproof.
  • Bluetooth / Zigbee room pods: they do not speak ProbeHarbor push ingest.
  • Uno + Ethernet alone: needs a LAN HTTPS relay; fine for advanced builds, not first kit.

DHT22 still works for shop air + humidity (your Ethernet garage case study). For pipes, prefer DS18B20. High-temp PTFE cable: Adafruit #642 if the probe sits near a water heater or heat tape.

Optional extras

  • Second DS18B20 on the same 1-Wire bus for door bay vs pipe wall (multi-zone).
  • Ventilated ABS enclosure + cable gland for the ESP32 in a dusty garage.
  • ELEGOO / generic ESP32 starter kits are fine if you still add a waterproof DS18B20: their bundled DHT11 is not the freeze probe.

Related

Amazon buy links may include an Associates tag. Adafruit and other vendor links are direct (Adafruit does not run an affiliate program). ProbeHarbor may earn a commission from qualifying Amazon purchases at no extra cost to you.

FAQ

Does ProbeHarbor sell an ESP32 kit?
No. ProbeHarbor is software. Buy an ESP32 and a waterproof DS18B20 from Adafruit or Amazon, then download a pre-filled ingest sketch from Dashboard → Devices. Parts list: probeharbor.dev/about/esp32-freeze-kit.

Is a DHT11 starter kit enough for pipe freeze?
Not by itself. DHT11 is weak below freezing and usually not waterproof. Use a waterproof DS18B20 for pipes; keep DHT22 for shop air and humidity if you want RH.

Do I need the Adafruit board specifically?
No. Any ESP32 DevKit that runs Arduino IDE or MicroPython works with the ProbeHarbor sketches. Adafruit links are stable reference SKUs; Amazon DevKit searches are fine for cost.