I am currently working with a customer that has a split phase system. There are two units (120v) that are connected as split phase. Only one of the units is now faulty . In a faulty split phase system is it possible to change just the faulty unit or both of the units need to be changed ? The reason for my question is that Victron highly recommends that the units need to be connected together in a system have to be similar i.e. same part number and a year of production etc. .Do we need to inform Victron through warranty so that both units to be replaced?.