Quick picks
- Best overall: Micro-Air EasyStart 364 — the proven best-seller, fits most 13.5K–15K RV A/Cs. Premium · ~$299
- Best for big / dual A/C: Micro-Air EasyStart 368 — Bluetooth diagnostics, supports larger compressors. Premium · ~$330–380
- Easiest install: SoftStartRV Universal — no-cut, well-documented wiring; dual A/C on 30 amps. Mid · ~$319
- Most compact: Micro-Air EasyStart Breeze — smaller unit for tight rooftop cavities. Mid · ~$200–270
- Best budget: TOSOT Soft Start Kit — lowest-cost way onto a generator/30-amp. Budget · ~$130–180
What a soft start does
A standard RV air conditioner pulls a big inrush of current — often 50+ amps for a fraction of a second — to get the compressor spinning (this is the "LRA," locked-rotor amps). That spike is what overwhelms a shared 30-amp post, a 2,000-watt generator, or an inverter, even though the A/C only runs at a fraction of that. A soft start ramps the compressor up gradually, cutting the inrush by roughly 70%.
| What it unlocks | Why it matters in summer |
|---|---|
| Run A/C on a 30-amp hookup | Older parks & crowded sites with low voltage stop tripping |
| Run A/C on a small generator | A single Honda/Champion 2,000–2,200W can start one A/C |
| Run dual A/Cs without a trip | Stagger startup so both units fit your service |
| Run A/C off battery + inverter | With a big lithium bank + 3,000W inverter, short off-grid cooling |
Class A note: many big coaches run a 15,000-BTU compressor and a 50-amp service — confirm the soft start is rated for your A/C's tonnage, and remember a soft start reduces startup surge, not steady-state running watts.
Compare the picks
| Product | Tier | ~Price | Best for |
|---|---|---|---|
| Micro-Air EasyStart 364 | Premium | ~$299 | Proven best-seller for most 13.5K–15K A/Cs |
| Micro-Air EasyStart 368 | Premium | ~$330–380 | Big or dual A/Cs with Bluetooth tuning |
| SoftStartRV Universal Kit | Mid | ~$319 | Easiest no-cut DIY install and support |
| Micro-Air EasyStart Breeze | Mid | ~$200–270 | Compact fit for tight rooftop cavities |
| TOSOT Soft Start Kit | Budget | ~$130–180 | Lowest-cost path onto a generator or 30 amps |
The reviews
Micro-Air EasyStart 364 (single-phase, up to 3 ton)
Premium · ~$299 · fits most 13.5K–15K A/Cs
The category benchmark and the model most RVers buy. It self-calibrates to your compressor over the first few starts and reliably cuts inrush by ~65–70%, so a single A/C will start on a 2,000W generator or a low-voltage 30-amp post. Proven track record and broad RV A/C compatibility.
Pros
- Proven, best-selling soft start
- Self-calibrating
- Fits most 13.5K/15K RV A/Cs
Cons
- Rooftop wiring install (or shop)
- One unit per A/C
Micro-Air EasyStart 368 (Bluetooth, 2–3.5 ton)
Premium · ~$330–380 · Bluetooth app diagnostics
The 364's bigger sibling: it supports larger compressors (up to 3.5 ton) and adds Bluetooth so you can watch start current and fine-tune in the app — handy on a big Class A 15K unit or when you're dialing in dual A/Cs. Buy one per air conditioner.
Pros
- Handles larger compressors
- Bluetooth monitoring/tuning
- Same trusted Micro-Air platform
Cons
- Costs more than the 364
- More capability than a small A/C needs
SoftStartRV Universal Kit
Mid · ~$319 · no-cut install, strong support
Built specifically for RVers, with clear model-by-model instructions and a no-wire-cutting install on many units. Cuts startup draw ~70% so you can run dual A/Cs on 30 amps or start one on a Honda 2200. Excellent customer support is a big part of why people pick it over the alternatives.
Pros
- RV-specific, very well documented
- No-cut install on many A/Cs
- Great support
Cons
- Similar price to premium Micro-Air
- One unit per A/C
Micro-Air EasyStart Breeze
Mid · ~$200–270 · smaller footprint
A more compact, lower-cost member of the Micro-Air family for tight rooftop cavities or smaller A/Cs where the full 364/368 won't fit easily. Same soft-start benefit in a smaller package — a good fit for Class C units and bunk-area A/Cs.
Pros
- Compact for tight installs
- Lower price than 364/368
- Trusted Micro-Air brand
Cons
- Best for smaller compressors
- Fewer tuning features
TOSOT Soft Start Kit for RV A/C
Budget · ~$130–180 · lowest-cost option
The wallet-friendly way to get onto a generator or a 30-amp post. It does the core job — meaningfully reducing startup surge — for roughly half the price of the premium units. Fewer bells and whistles and a shorter track record, but a solid value for a single A/C on a budget.
Pros
- Lowest price
- Reduces startup surge effectively
- Good for one A/C on a generator
Cons
- Less proven than Micro-Air/SoftStartRV
- Fewer install resources
How to choose
1. Match it to your A/C's size
Most rooftop RV units are 13.5K or 15K BTU (about 1–1.5 ton); the 364 and SoftStartRV cover these. For a big 15K on a Class A, or if specs are borderline, step up to the EasyStart 368.
2. One per air conditioner
If your coach has two rooftop A/Cs, you need two soft starts (and they let you stagger startup so both fit your service).
3. Know what it does — and doesn't
A soft start slashes the startup surge, not the steady running watts. It lets a generator/30-amp/inverter start the A/C; running a second big load at the same time can still be too much.
4. Plan the install
Most installs are a rooftop wiring job inside the A/C shroud — very doable for a handy owner in an hour, or have a shop do it. SoftStartRV's no-cut kits and per-model guides are the friendliest for DIY.
Frequently asked questions
Can a soft start let me run my RV A/C on a 2,000-watt generator?
Often yes for a single unit. By trimming the startup surge by roughly 70 percent, a soft start lets a 2,000 to 2,200-watt inverter generator start one 13.5K or 15K air conditioner that would otherwise stall it. The generator still has to handle the steady running load once it is going.
Will a soft start let me run the A/C off batteries and an inverter?
It makes it possible for short periods with the right setup, but it does not reduce running watts. You need a large lithium battery bank and a roughly 3,000-watt inverter to sustain the air conditioner, and runtime is limited by battery capacity.
Do I need one soft start per air conditioner?
Yes. Each rooftop A/C compressor needs its own soft start. The benefit on a dual-A/C coach is that you can stagger the two startups so both units fit within your electrical service.
Will a soft start fit my Class A motorhome's 15K A/C?
Most likely, but confirm the device is rated for your compressor's tonnage first. The EasyStart 364 covers most 13.5K and 15K units, while the 368 supports larger compressors up to 3.5 ton and adds Bluetooth tuning for big coaches.
How hard is a soft start to install?
Most installs are a rooftop wiring job inside the air conditioner shroud and take a handy owner about an hour, or a shop can do it. No-cut kits like SoftStartRV with per-model guides are the friendliest for DIY.
Related guides
Best RV Roof Vent Fans
Cool the rig on mild nights without running the air conditioner at all.
Read the guide →Best RV Solar Kits
Build the off-grid power that, with a soft start, can run an A/C away from hookups.
Read the guide →Best RV Surge Protectors
Guard your A/C and electronics from low voltage and bad pedestal power.
Read the guide →