Nissan Patrol 4x4 (Africa)

I have two questions here:

Firstly where can I have my two Indel B's serviced?

Secondly I have always wondered, can one connect both the 220V and 12V cables on the fridge at the same time? ie does on override the other one, like for instance where there is 220V via generator which then gets switched off at some stage during the night then the 12 V will just take over??

national luna are the agents for them
it depends on specific fridge some you can some you cant just speak to the agents
my way of doing it is to leave the fridge on 12v and connect may 220v battery charger at night to put power back in if power falls away the fridge runs of the dc