Yanche, that is exactly what I would like to do with my generator, back feed the entire house panel.
Once utility power is lost I want to be able to shut off the main and breakers inside the house panel and start the generator and hit the disconnect sending generator power to the house panel then turning on the breakers for where I want to feed the power like hot water for a shower ect.
What size generator and wire did you use to do this and did you use a single circuit of 220 output from the generator to feed the house panel ? Just thinking of gathering parts so I can get mine done soon.
We have an old 220 line in the old garage and soon to be master bedroom we are using right now that was there for a dryer. We're going to set some kind of deal up outside in the future. We have a really long extension cord by brother had been using for a mig welder.
If you want to do it right they have a mechanical system for the panel that prevents both breakers from being on at once. Another thing I saw was some kind of sensor you wrapped around the wire from the street. It had an alarm to tell you when the power came back on.