Build log: tearing into the rig

Time to put skin in the game. Here's the current project: a full rig overhaul, documented as it happens, including the parts that go wrong.

Air conditioning. The heaviest single load in any rig. The real question isn't which AC — it's whether a soft starter lets it run off battery instead of demanding shore power. That decision cascades through the entire electrical design.

Furnace / heat. Propane furnaces are thirsty on both propane and 12V; the blower runs constantly. A diesel air heater sips fuel and draws very little once running — but the glow plug spikes hard at startup, which the bank has to absorb. Vented combustion either way. No unvented heat where anyone sleeps.

Toilet. Composting means no black tank, no dump station, no plumbing. The trade is emptying solids periodically and a small fan on continuous 12V.

Water. Pump, filtration, tanks. On-demand pumps are intermittent loads, easy on a bank — but an accumulator tank stops the pump short-cycling itself to death.