wich are the limits for thermometer?

hi Mike
I update to version 5.6.2 and trying to intoduce a degradate colored scale for thermometer and I nead to know values for low and max temperatures.
Reason is because after update I get this display where 7?C requires half scale.
http://personal.auna.com/xav58806/images/ww.jpg
thanks at advance
Xavi