I have found that the only successful way of refilling a system having emptied is to poor in the coolant in very slowly so as not to produce a "water block" which stops the air coming up the hoses as the water goes in to displaces it, every so often stop for a few minutes, and, as Lee says, squeeze the lower rubber hoses a few times, and you will see air bubbles comming up into the reservoir. When you have got as much as possible in, screw the cap on, and go for a 10min run (not stationary), you then have to leave the engin to cool before unscrewing the cap in order to repeat the process. If you dont allow the engin to cool, it is likely to blow back the coolant when you remove the cap. According to my info there is 15 litres of coolant in the system, so keep a check of how much you put in, and that will give you a guide as to when it is full. The only other thing I would do in the case of the Alp, is, before refilling, unscrew the two bleed valves, and do them up only when fluid starts to run from them, that way air can escape from another two places during the fill. But make sure they are done up before you go for the run.
This is one of the times when what appears to be a long winded process, turns out to be the quickest in the end
1990 GTA Atmo, 2003 Jaguar X type 2.5SE Auto, 2018 Kia Picanto GT-Line-S 1.25