Environmental Conditions — Fixed combined coefficient bug

Last Updated: 
Tuesday, September 5, 2017

Software/Versions Affected:

In the Environmental Conditions Library Convection section, if the Model is set to "Fixed combined coefficient", the fields Effective Sky Temperature (for U-factor Outside) and Effective Room Temperature (for U-factor Inside), both of which are hidden for this model, may be set incorrectly. The work around is to temporarily set the Model to "Fixed convection coefficient" so that the fields are visible, set them to the "Inside Air Temperature" value for the U-factor Inside tab and to the "Outside Air Temperature" value for the U-factor Outside tab, then set the Model back to "Fixed combined coefficient".

The example below is for the U-factor Outside tab — repeat the steps for U-factor Inside tab also.


Fixed Combined Coefficient — Effective Sky Temperature field does not show


Change the Model to Fixed Convection Coefficient and the Effective Sky Temperature field shows. Check to see that it has the same value as the Outside Air Temperature


If the Effective Sky Temperature is not equal to the Outside Air Temperature, change it so they are the same


Change the Model back to Fixed Combined Coefficient after changing the Effective Sky Temperature to be equal to the Outside Air Temperature