Hi, congratulations on your home and the central vac. We made that vacuum and would love to assist you. When the hose is inserted into a wall inlet, and the switch on the hose handle is activated, the suction starts - if no switch then the suction starts upon insertion. The wire nuts you see on the low voltage wire is fine. It will not shock you. The on/off switch on the unit can be used when you insert a hose into the utility valve on the front. The manual you need is here www.builtinvacuum.com/manual
and the parts and accessories here www.builtinvacuum.com/help/md.html
. Oh, and yes, these are the bags you need.