I am not fully following your question but the program looks pretty good. The program flows from the top to the bottom with no confusing gotos and gosubs which is good.
There’s one small improvement you can do which is to add a little hysteresis:
20 IF IECS > VAR10 THEN START OECS
30 IF IECS < VAR10 - 1 THEN STOP OECS
Line 51 looks suspicious because the PID1 will not go below 0. Change it from this
51 IF PID1 < 0 or PID2 < 0 THEN START ORAD ELSE STOP ORAD
To this:
51 IF PID1 = 0 or PID2 = 0 THEN START ORAD ELSE STOP ORAD
You can change the wording a little to make it easier for later maintenance, instead of IF OECS > 0, use this:
70 IF OECS OR ORAD THEN START OCOLL ELSE STOP OCOLL
Give VAR5 a user name as well.