Welcome to the forum Jimmy.
I don't have a .pdf manual, I'm afraid (and neither do I have a hard copy to hand just at the moment), but with Little Sisters, Error 1 generally indicates an interruption to the mains power supplying the unit.
Not sure about the 5, but on the LS-3 Error 3 indicates that water has failed to enter the chamber (from the reservoir). So I would take a look at that. For instance:- are the users keeping sufficient water in the reservoir?