The rainy weather made time for a long postponed indoor project: temperature sensing to make the domestic hot water circulation smarter.

The rainy weather made time for a long postponed indoor project: temperature sensing to make the domestic hot water circulation smarter.

Two DS18B20 temperature sensors are taped to the outlet and return pipes and connected to a Wemos D1 mini board running esphome. The data flows to Home Assistant where it’ll be used to decide whether and for how long to run the circulation pump.