How do I change the Outdoor Design Temperature (ODT) for my project? To change the ODT, follow these steps: Note this will not affect the Outdoor Low Temperature (ODL) used in the performance task. Read here for more information.  Navigate to the Plan task  and the  Sources  tab  Below the sound heat pump load and sound check, click  Outside design temperature Set the temperature you want to use An additional  0.3°C  will need to be removed for every  50 m above sea level, with altitude given in the input section of the technical report & customer proposal.