Issues with gross error detection

I have a problem with my model, I am using the model to calculate the mass balances, however, one of the flows is bigger than the others, this causes to detect it as a flow containing gross error. The messurements are ok since is a combustion process where the air is much bigger than the other flows. Does anyone know what can be done to prevent the software from detecting it as a flow with gross error?

It has not necessarily something to do with the size of the flow. It depends on your model structure and the uncertainties you have assigned to your input data.