This summer I created a pool temperature monitoring and pump control system using a Pi Zero W. This article gives an overview of the system and how I put it together. It allows the temperature of the air and water to be displayed on a web page while automatically turning the pump on and off according to a preset schedule.
The Pool
We originally had an 8ft Bestway “fast set” pool with an inflatable ring around the top. This proved to be slightly incompatible with the 3 cats we share the garden with. So this year we changed it for a 10ft metal framed “Summer Escapes” pool. It holds 4100 litres of water and I had no idea what temperature the water ever reached or how this related to the air temperature. I also had no way of easily controlling the pump without fiddling with the settings on a mains timer.
The Requirements
I decided I should be able to create a system that could :
Measure the air and water temperature
Log temperatures to the internet
Display temperatures on a web page accessible from a mobile phone
Allow the pump to be turned on, off or placed in an automatic mode that would follow a schedule
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Each Friday is PiDay here at Adafruit! Be sure to check out our posts, tutorials and new Raspberry Pi related products. Adafruit has the largest and best selection of Raspberry Pi accessories and all the code & tutorials to get you up and running in no time!