Thanks for the confirmation on the F2 problem.

Another problem I am still facing is in regard with the head-dependent
orifices.

First, according to the SWMM manual, F3 should be for timed closure
gated NKLASS 11-14. According to the manual, these NKLASS use the same
input information needed for the corresponding NKLASS 21-24? Thus both
types do the same job, head-dependent controls! So the question is what
is the difference between orifices with F3 controls and orifices with F4
controls if both need the same info (controlling node name, elevation to
open, and elevation to close the gate?)

Second, in using the head-dependent control F4: the output file
indicates reading the F4 line defining the head dependent orifice (I
tried NKLASS 21 and 23), but the results show that the orifice did not
close at the needed depth!

Any help in clearing these two points will be appreciated.
Thanks in advance.
Hazem