With the addition of a few extra sensors Segmeter does a really smooth job of trending the temperatures on our solar hot water system. The DS18B20's on the one-wire bus is a great way to go for economical temperature monitoring.

Good to know that even in Melbourne winter the water temperature can still get to 50 deg C. Also note the wiggle in the LH trend down low on the first day. This is the freeze protection controls kicking in to protect the panels on that rather cool morning.

Good stuff!

Rob