What Size Generator for RV Air Conditioner (15,000 BTU)? (Startup vs. Running Watts)
Standard RV AC needs 3,300W+ to start — but a Soft Start kit changes everything.
Wattage at a Glance
Danger Zone — Compressor Surge
15,000 BTU compressor draws 2,800–3,300W for 1–2 sec on startup
Quick Reference
- Running Watts
- 1,500W
- Starting Surge
- 2,800–3,300W
- Without Soft Start
- 3,000W+ generator required
- With Soft Start Kit
- 2,000W generator (EU2200i) works
- Soft Start Cost
- ~$300–$400 installed
The Soft Start Kit That Unlocks Your 2,000W Generator for RV AC
A 15,000 BTU RV rooftop air conditioner is the most common appliance that trips up RV travelers. While it only draws 1,400–1,700W running, the startup surge hits 2,800–3,500W — more than most 2,000W inverter generators (Honda EU2200i, Yamaha EF2200iS) can handle.
The solution is a Soft Start kit — specifically the Micro-Air EasyStart or the Victron EasyStart. These capacitor-based modules are wired into the AC unit's compressor circuit and electronically ramp the motor speed up over 1–2 seconds, cutting the startup surge by 50–70%.
With an EasyStart kit installed, the same 15,000 BTU AC that normally surges to 3,300W will only surge to about 1,800–2,000W — well within the capacity of a Honda EU2200i running in parallel mode.
If you'd rather not modify the AC unit, a 3,000–3,500W generator like the Honda EU3000iS or Champion 3500W handles a standard 15,000 BTU unit without any modifications.
Recommended Generators for This Load
Prices and availability are accurate as of March 23, 2026 and are subject to change.
2,200W starting
Honda EU2200i (2,200W Inverter)
$1,099 – $1,199
The classic RV setup: ultra-quiet inverter + EasyStart kit handles 15K BTU AC reliably.
Check Current Price on AmazonReduces surge ~70%
Micro-Air EasyStart 364
$329 – $369
Soft starter kit — essential for running RV AC on a sub-3000W inverter generator.
Check Current Price on Amazon3,000W starting
Honda EU3000iS (3,000W Inverter)
$2,299 – $2,599
No modifications needed — handles 15,000 BTU RV AC out of the box.
Check Current Price on AmazonAs an Amazon Associate, GeneratorPicker earns from qualifying purchases.
Frequently Asked Questions
Can a Honda EU2200i run a 15,000 BTU RV air conditioner?
Not without a soft start kit. The EU2200i's 2,200W surge capacity is below the 3,300W the AC needs to start. Install a Micro-Air EasyStart 364 on the AC unit first, and the EU2200i can handle it — many full-time RVers use exactly this setup.
What is the best generator for a 15,000 BTU RV AC?
Without modifications: Honda EU3000iS or Champion 3500W. With a Soft Start kit: Honda EU2200i (single unit) or two EU2200i units in parallel mode for extra headroom plus other appliances.
Running multiple appliances at once?
Use our free wattage calculator to add up all your loads and find the exact generator size you need.
Calculate My Total Wattage