This post is mainly for our US friends and all the other countries using Fahrenheit scale. By default the hydrosys4 SW is set to Celsius, to change it you can do the follow: Go to HardwareSetting page, you will see a table, if you look at the temperature row you will see the item "unit" set to "C". Now you need to set this to "F". Click the edit button, locate the "tempsensor" name and change the relevant unit to "F". Scroll down and click the green button "Confirm and save". Now the temperature reading will be shown in Fahrenheit.