We're Running Electrical in Our DIY Camper Build!

Camper build electrical + prep progress (key storyline)

• The team is converting an 8.5 x 16 cargo trailer into an “ultimate adventure rig,” moving from insulation/window work into wiring.
• They reconsidered a previous cooling plan: a rooftop RV AC mount was unpopular due to concerns about road performance, potential roof concavity/water pooling, and water damage—so they pivoted away from that approach.

Cooling plan change: rooftop AC → Mr. Cool Monoblock

Community feedback pushed them toward alternatives, especially mini-splits, but mini-splits require a large exterior condenser unit, which they didn’t like visually.

New plan

• Order/pre-order a Mr. Cool Monoblock wall-mounted system (about 9,000 BTU; using the “Monoblock” design with only two small exterior vent holes).
• They note a comparison point: many systems marketed as higher BTU RV ACs may still rely on a 9,000 BTU compressor, so they believe the 9,000 BTU rating could be sufficient.
• They intend to test the AC once it ships (they paid for it; it’s not a sponsored freebie).

Vehicle/trailer lighting wiring goals (switch to battery power)

Before finishing RV interior wiring, they troubleshoot and rework parts of the trailer lighting:

• They map existing wire runs and identify likely functions (e.g., turn signal/brake-related wires).
• Main goal:
  • Remove/disable the factory exterior lights from the truck’s power/control.
  • Rewire them so power comes from the camper’s batteries via an interior switch.
• Verification step:
  • Temporarily hook up the truck to confirm what works (running lights, blinkers, brake lights).
  • Fix grounding/wiring issues when rear running lights/blinkers don’t behave as expected.

Staying efficient while wiring (process + lessons)

• They remove existing exterior light wiring first, then rework so:
  • Fewer dangling wires remain inside the trailer.
  • They can finish insulation/woodboard placement without wires getting in the way.
• They avoid “redoing” later by testing early:
  • They specifically try not to bury wires only to discover a light doesn’t work.

Partnered supplies (eTrailer, plus U-Haul materials)

They’re partnered with eTrailer, using it as a one-stop shop for RV build components.

Key items shown/explained for the electrical “base” phase

• A distribution/fuse panel system (needed because they’re building from scratch)
• A 30-amp RV inlet (planned for outside mounting so the shore power cord can connect)
• Planned exterior outlet access for convenience
• A “furnace thermostat” component for their future heating setup

They also thank U-Haul Trailer for sending materials used during the project phase.

Ventilation plan (roof exhaust fans)

They confirm they’ll install small, low-profile roof exhaust fans:

• One fan over the kitchen
• Another fan over the bathroom
• Each is stated as about 100 CFM (per the subtitles)

Electrical design overview: batteries + hidden cabinet wall

Planned layout (shown as a “vision,” not fully built yet):

• Batteries sit near a tire well area, inside a future contained/structured placement.
• A “false wall” area will hold:
  • Inverter
  • Fuse box / breakers
  • Solar controllers
• The goal is to hide messy wiring behind the wall while keeping cabinets accessible.

Wiring strategy: breaker/fuse planning + channel routing

They stress planning circuit paths before running wires.

Circuit + wire planning

• Pre-decide which circuits go to which breaker types:
  • 120V AC dedicated wiring (noted as running 12-2)
  • Kitchen outlets on 12-2
  • 12V circuits using smaller wire sizes:
    • Mostly 12-gauge
    • 10-gauge for the more power-hungry fridge
  • Some outlets on 14-gauge for 15-amp circuits
• To protect insulation and maintain efficiency:
  • They cut grooves/channels into insulation so wires can sit without squishing it (compression reduces R-value).
  • They avoid creating bulges in the finished wall.

Cutting channels tool/labor notes

• They use a blade/tool to create channels and even suggest adapting it (bending a blade tooth) to widen the path.
• They cut/trim wood components where wires cross (without removing major supports), so runs stay straight and clean.

Wiring execution highlights (what gets run)

• They run wires “one line at a time” and leave extra wire hanging until the finished distribution panel can be installed.
• They label wires instead of installing everything immediately (distribution panel waits for later wall finishing).
• They route and complete:
  • AC and some outlet runs
  • Microwave outlet
  • Dedicated outlets for the kitchen and around appliances
• Kitchen/fridge flexibility:
  • They plan a possible 12V vs 120V fridge option:
    • They include infrastructure/outlets behind where the fridge will go so they can choose later.
• General outlet philosophy:
  • More outlets are better (and they avoid sharp wire creases; prefer gentle curves).

Final “electrical engineering” setup explanation (distribution panel + bus bars)

Once wiring is partially complete, they explain the system:

Distribution panel + breakers

• The distribution panel from eTrailer includes:
  • Incoming power lines
  • Breakers for AC and 12V circuits

Cable types (summary)

• Red wires = main 12V power lines feeding key devices (fridge, water heater, etc.)
• Mostly 12-gauge, except 10-gauge for the fridge
• AC outlets mostly on 12-2
• Some charging/low-load outlets on 14-gauge

Negative distribution (bus bars)

Instead of running every negative wire individually, they plan/mention:

• A negative bus bar (plus a second one near the ceiling) to reduce wire runs and cost/complexity.

Safety planning (fusing/breaker sizing)

• 14-gauge → 15-amp breaker
• 12-gauge → 20-amp breaker
• Fuses used where appropriate for the circuit

Notable locations / products / brands / speakers (end)

• Brands/Products: Mr. Cool (Monoblock), eTrailer (distribution/fuse panel, RV inlet accessories), U-Haul Trailer (materials sent), Dexter (mentioned in context of a thermostat/fan-related item)
• Key equipment:
  • 30-amp RV inlet / power cord inlet
  • Inverter, fuse box, solar controllers (planned for the false wall)
  • Roof exhaust fans (~100 CFM each)
  • AC system: Mr. Cool Monoblock ~9,000 BTU
• Speakers/crew: Victoria and Craig (main builders/voices during wiring and planning)