Comparison between the observed (black) and best-fit model H₂O line profiles for IRAS4A both with (red) and without (blue) including absorption against the outflow and by foreground clouds as described in Sect. 3.5. The green error-bar in the lower left corner of each plot indicates the 1σ_rms uncertainty in the observations. For some lines, both the model and the data are scaled up by a factor indicated in the panel to aid comparison.