Sumproduct by month that excludes text

This works for me:

Formula:

=SUMPRODUCT((MONTH(Sheet1!C$1:C$3)=2)*(Sheet1!B$1:B$3<>"NWR")*Sheet1!A$1:A$3)

Note that SUMPRODUCT can be a bit clunky on large datasets. You could use SUMIFS to do similar.

BSB