Qualifying models, according to the internet, use code 46H2. You may want to contact the seller and confirm your model, the correct code and that you qualify for the Residential Energy Credit.
Common qualifying Weil-McLain models include:
Eco Tec (80, 110, 150, 199)
Evergreen (110, 155, 220, 299)
AquaBalance (80, 120, 155)
Simplicity (110, 150, 199)