Take a look at the following help article:

http://help.infragistics.com/Help/NetAdvantage/NET/2008.2/CLR2.0/html/Gauge_Creating_a_Linear_Gauge_Using_the_Gauge_Presets.html

There should be two gauges there for a thermometer type.  Once you load them, you can modify the elements to have different ranges and different colors.

Help section on Gauges that will show you how to work with the built in designer:

http://help.infragistics.com/Help/NetAdvantage/NET/2008.2/CLR2.0/html/WinGauge.html