Outage scenario
RV Weekend Generator Sizing (AC + Essentials)
Data reviewed ·how we calculate
The weekend boondocking build is the RV question in its natural habitat: roof air conditioner plus the modest everything-else of camp life — the compressor cooler, lights, charging and a fan. The math lands at exactly 4,000W with headroom, which explains the two rigs you see in every no-hookup campground: one 3,500–4,500W portable, or the beloved pair of 2,200W inverters on a parallel kit. This page’s calculator is pre-loaded with the build; swap the AC to 15K BTU or add loads and watch the classes shift.
Build your load — check what must run at the same time
Totals update live. Surge math assumes staggered starts: plug loads in one at a time, largest motor last. 25% headroom applied.
The load math, spelled out
Running watts: roof AC 1,500W + camping essentials bundle 200W = 1,700W. Largest single starting delta (staggered starts): the AC compressor’s 3,000W − 1,500W = 1,500W dwarfs the cooler compressor’s 150W. Peak = 1,700W + 1,500W = 3,200W. With 25% headroom: 3,200W × 1.25 = 4,000W — the exact midpoint of the 3,500–4,500W class, or two paralleled 2,200W inverters (~4,400W combined). All 120V; RV shore-power systems on 30A rigs are 120V throughout.
Running this build, step by step
Start the generator (or both paralleled units) and let the rig’s converter settle — if the house batteries are deeply discharged, the converter alone can draw ~500W until they recover.
Bring the AC online with the batteries at least partially recovered and other discretionary loads off: the 3,000W compressor start is the weekend’s defining electrical moment.
Once the AC is cycling, the essentials ride along invisibly — 200W against a 3,500W+ supply — and the microwave can take turns with the AC on all but the most marginal setups.
Observe quiet hours (typically 10 p.m.–6 a.m., generators off): pre-cool the rig hard before cutoff, run fans on batteries overnight, and restart cooling after coffee.
Pro tips
- Check your nameplates first — every figure on this page is a planning estimate built from typical values; your appliances' labels beat any chart.
- Position the generator downwind of every rig in the loop — yours and the neighbors’ — with exhaust away from windows and vents, and confirm the RV’s CO detector has a fresh battery before the first night.
- A soft-start kit on the roof AC (see the RV AC page) turns this whole build into single-2,200W-inverter territory — the best per-dollar upgrade in the boondocking world.
The data behind this scenario
| Load | Figures | Source |
|---|---|---|
| Roof AC, 13,500 BTU | 1,500W running / 3,000W starting (delta +1,500W) | Dometic/Coleman specs; RV sizing guides |
| Camp essentials (cooler, lights, charging, fan) | 200W running / 350W starting | Itemized on the camping essentials page |
| Converter/charger when batteries are low (add if applicable) | up to ~500W extra | WFCO/Progressive Dynamics converter specifications |
| Voltage | 120V (30A rigs) | RVIA electrical standards |
Each appliance in this build has its own page with full ranges and sources:rv air conditioner, camping essentials bundle.
RV weekend setup questions, answered
What size generator do I need for an RV weekend with air conditioning?
The classic build — 13,500 BTU roof AC plus cooler, lights, fan and charging — runs 1,700W with a 3,200W peak at compressor start, which is 4,000W with the 25% headroom. That means one 3,500–4,500W portable, or two 2,200W inverters paralleled for ~4,400W. The 15K BTU version of the same build peaks at 3,700W (4,625W with headroom) and genuinely wants the top of the class or the parallel pair.
One 4,000W generator or two paralleled 2,200W inverters — which should I buy?
The pair costs more and wins on everything else RV-shaped: ~50 lb per unit instead of one 120 lb back-breaker, 50–60 dB instead of an open-frame roar (campground diplomacy is real), redundancy (one unit still runs everything but the AC), and single-unit mode for no-AC weekends at whisper fuel burn. The single 4,000W open-frame unit wins on price and simplicity. Campground-social RVers overwhelmingly land on the pair; driveway-and-desert types keep the big single.
Where does the microwave fit in this math?
In turns, on most setups. RV microwaves draw ~1,500W input; with the AC running (1,700W total) that is 3,200W continuous — inside a 4,400W paralleled pair’s comfort zone, but on a single 3,500W unit it collides with the AC compressor’s restarts. The camp-tested pattern: let the AC hold temperature, pause it (or wait for a compressor-off cycle) for the three minutes the burrito needs, resume. The calculator above will show you exactly where your combination stands.
How much fuel should I bring for a weekend of boondocking with AC?
Plan around the AC’s appetite: heavy afternoon cooling plus evening essentials typically burns 3–5 gallons per day on inverter units (more on open-frame). A Friday-to-Sunday weekend with hot afternoons is a 6–10 gallon commitment — bring it in proper cans, because the nearest gas station is the thing boondocking is avoiding. Shade parking, roof-vent insulation and pre-cooling before quiet hours all shave real gallons; the essentials without AC, by contrast, sip under a gallon a day.
Related pages
- RV Air Conditioner Generator Calculator (13.5K & 15K BTU)what size generator to run rv air conditioner
- Camping Essentials Generator Calculatorwhat size generator for camping
- Tailgating Generator Size Calculatorwhat size generator for tailgating
- Microwave Generator Size Calculatorwhat size generator to run a microwave
See alloutage scenarios or build your own combination in themulti-appliance builder.
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