daiken splits difference between f3 alarm and e4

Hi guys I am new to this forum so please dont be too harsh my background has been mostly chillers so pretty new to air con I was at a site today 4 splits 3 showing code f3 and 1 showing e4 further inspection the e4 unit short of gas but the others high discharge temp could this be down to shortage of gas or possibly one of the fans is not rejecting latent heat

Thanks