I am not sure where U=1.69 comes from. Since I don't speak Spanish, I don't quite get the meaning of various quantities, but from EN 10077 standard, Psi value is calculated by subtracting heat flow for actual glazing from heat flow for insulating panel. From this example, Psi value might be calculated by subtracting 2D heat flow (with thermal bridge) from 1D heat flow for wall element without the thermal bridge. So, going back to U=1.69, is that the U-factor for the same wall section, but without thermal bridge? Or is U=1.28 correct value?
In general, as far as 2D calculations are concerned, THERM gives pretty darn correct answer.
Charlie