Magnetic DS18B20 temperature sensor holder for water heater

thingiverse

This is a holder for the DS18B20 temperature sensor designed to be attached to a water heater to monitor the water temperature. It can be fitted with four 6x3mm neodymium magnets such that it attaches to the stainless steel tank right next to water heater's thermostat. This setup is typically used to make sure the water is heated to safe levels (+70C) frequently enough to kill off legionella bacteria. This is useful when the water is turned on only during the hours of the day with the cheapest electricity prices. This avoids messy heat resistant glues or tapes. Apply some thermal paste for the most accurate measurements. The design is based on https://www.thingiverse.com/thing:5457784 by 3dprint4fun. I added curvature to fit the diameter of a 300l tank (50cm diameter), holes for magnets, moved the sensor closer to the tank (no space in-between), and lengthened it a little. I also made a clamp-on holder meant for the water heater's outlet pipe: https://www.thingiverse.com/thing:5605200