Data Logging: Results!

As of last night I completed hookup of the eighth 1-wire temperature sensor.  It is reading at the hot inlet to the mixing valve, which is also the outlet to my old 30 gallon hot water heater.  This will give me an idea of the performance of the mixing valve and it's settings, as the difference between the "Domestic Hot Water Supply" and the measurement read at this sensor is how much cold water is being mixed into my hot water supply.

The data that I am generating is being put, for each sensor, into an RRDtool database every 30 seconds.   I have no idea what a good sampling frequency is, so I settled on this one because it sounded about right.   I will probably blow away this database and recreate it a few times in the next week or so trying to get it 'just right'.

Here is the dataset for the last four hours today:

The lines I found most interesting are the roof (red), solar storage tank temperature (green) an domestic hot water supply (should be magenta, but looks red!).  DHW supply roughly shows the usage during the afternoon.  I very much dig the slow but steady rise of the storage tank temperature!