I have not written up this project yet with photos, but here is a summary.

A Raspberry Pi hooked up to DS18B20 temperature sensors to monitor the temperature of the pool, heater output and ambient air temperature.

A program written in Python periodically reads the temperatures and compares them. The current system temperatures and pump state is logged to Azure table storage.

When the heater tempearture is over the pool temperature then a relay is switched on, starting a pump to circulate water through the solar heater panels.

At the moment the pool is closed for the season so this project is just monitoring ambient room and in-the-sun temperatures to simulate.

See the monitoring page

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