RV AC Power Checker
Last updated: September 3, 2026
Quick answer
A 13,500 BTU RV AC needs ≈1,500 W running and up to ≈2,800 W to start. A 30 A hookup (3,600 W) runs it
easily; a 2,000 W generator needs a soft starter to survive the start; a 3,000 W+ generator handles it alone.
Verdict
—
Real numbers for RV air conditioners
| Unit | Running watts | Starting surge | With soft starter | Notes |
|---|---|---|---|---|
| 13,500 BTU | 1,300–1,800 W | 2,750–3,000 W | ≈ 980–1260 W | Run figure is the compressor + fan under load |
| 15,000 BTU | 1,500–2,000 W | 3,000–3,600 W | ≈ 1120–1440 W | Run figure is the compressor + fan under load |
Source: Micro-Air's published sizing guidance (≈1,500 W run / ≈2,800 W start for 13.5k BTU, microair.net) and community measurements (≈13 A run / ≈22 A start). Your unit's compressor spec plate is the final word.
What the check accounts for
- Start vs run: the source must cover running watts + your extra loads continuously, and the start surge momentarily.
- Soft starters: cut compressor surge ~60–70% (Micro-Air's published figure), which is what makes small inverter generators viable for AC.
- Battery-only inverters: the same watts become battery amps — a 1,500 W run is ≈140 A at 12 V. That is a bank-and-wiring question as much as an inverter question (see the inverter size calculator).
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Rules of thumb that hold up
- 3,000 W generator, no soft starter: starts one 13.5k BTU AC by itself, little else at start time.
- 3,600 W (30 A service equivalent): one AC + fridge + lights comfortably.
- Two 2,000 W units paralleled (4,000 W): the classic "run one AC plus the microwave" setup.
- Anything smaller: only with a soft starter, disciplined load shedding, or 50 A shore power.
Frequently asked questions
Can a 2,000 watt generator run a 13,500 BTU RV air conditioner?
Not without help. The compressor needs up to ≈2,800 W for the first second at start. With a soft starter (e.g., Micro-Air EasyStart) cutting the surge 60–70%, the same 2,000 W generator usually starts and runs it — thousands of RVers do exactly this.
How many amps does an RV air conditioner use?
Roughly 13 A running and 22 A at startup for a 13,500 BTU unit on 120 V, per community and manufacturer measurements. That is most of a 15 A household circuit and about half of a 30 A RV service.
Does the fan or the compressor use more power?
The compressor. The fan alone is a few hundred watts; the compressor adds the rest of the running load and nearly all of the start surge.
Related tools & tables
reference
RV appliance wattage chart
reference