In the last couple of weeks we installed the new electric head in the aft stateroom and also the new Technautics Cool Blue compressor for the refrigerator and freezer. When we got ready to install the head, I had to find a proper breaker location for it. Originally I was hoping I could just tap into the 12 volt lighting circuit in the head.
As I read the instructions, it called for a 20amp circuit, so I ran the correct gauge wire to the distribution panel and used a breaker that was not being used for anything else.
Over the years since 1978 when the boat was built, much of the labeling on the wires from the breaker to the distribution bus have come off and some new wiring was not labeled. I took the time to sketch out the back of the panel and then trace all of the wires from the 12Volt battery selector to the positive bus bars to the breaker to the distribution bus. Like most things as we have worked on this project, if it was not documented, then we have created and saved the documents into a new Boat Book to capture all wiring, plumbing, networking and any other diagram that I may need later when working on, or enhancing the boat.
The next step is to add the Refrigerator/Freezer to their own dedicated breaker as well. It will end up being breaker 9 because the windlass is actually on it's own high amperage switch that must be activated from the engine room. (Due to the high amperage required when pulling up many feet of chain with the windlass, it was made it a point to not run the windlass unless the engine is running and replenishing the batteries)
The next step will be to create a similar schematic for each of the different AC panels. The reality is I likely won't do it until I need to rewire something on the AC side of the panel. So maybe it will be within the year when we end up replacing the rear air conditioner with one that doesn't sound like a freight train.