ProbeHarbor does not sell hardware. 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.
Recommended freeze BOM
| 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
- 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
- Create a free account and a push device on Devices.
- Download the pre-filled Arduino
.inoor MicroPython.py(ingest URL filled in). -
Set Wi‑Fi only, flash per
ESP32 flashing options
Serial 115200 should show
POST 200. - Optional: print the ingest kit QR on the enclosure.
- 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
- Adding push and pull devices
- ESP32 flashing options
- Raspberry Pi Pico W ingest
- Kit QR onboarding
- Probe mount kit
- Hardware accessories
- Probe mounting and enclosures
- Freeze season checklist
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.