I've been trying to investigate energy consumption for a hospital in Mexico City. The space heating is giving me a zero for a few months then dashes for the rest. I've modeled based on climate zone 3. I've tried all three weather files for Mexico City, Mexico88, 90 and 91. In efforts to verify the model was correct, I changed weather files for different locations in the US. I even tried a US climate zone 3 and it showed some space heating. Is this an issue with the weather file or is there just no real space heating. The system used was a dx with electric reheat. The attached pdfs show the numbers.
Thanks for any direction provided.

BRIAN J. WOLFE, CDT, LEED AP BD+ C