Inverter vs Non-Inverter Aircon on Solar: Startup Surge and the Realistic Choice

For solar with a battery or power station, an inverter aircon is the realistic choice. It slows its compressor once the room is cool instead of switching on and off at full power, so the battery lasts longer and the power station sees fewer hard starts. Pick a true inverter unit such as the Kolin KA-100GQAIINV32 or TCL TAC-11CSD/P7, and give it a station with plenty of headroom, such as the EcoFlow DELTA 3 Max.

What makers actually publish about startup

There is no starting or inrush current published for any of the aircons in our verified data, inverter or not. The Midea, Samsung and Everest spec pages we checked give only running or rated current. For example, Midea PH lists 3.61A rated current for the MSCH-10CRFN8, and gives no starting figure. Compressors can draw more than their running watts for a moment when they start (our runtime guide covers this), so the safe approach is:

1. Find the highest power figure the maker gives, not just the rated one.
2. Choose a station whose continuous AC output is well above it, with a surge rating on top.

Inverter units help here because many publish a power range:

The UB2’s 1,450W top end is above the DELTA 3 2000 Air’s 1,000W output, but well within the DELTA 3 Max’s 2,400W continuous (4,800W surge).

Why fixed-speed units are harder on a battery

A non-inverter (fixed-speed) aircon has one speed. When the room warms up, the compressor switches fully on at its rated watts. When the room is cool, it switches off. Every cycle is a fresh start, and while it runs, it draws full power.

An inverter unit runs continuously but at lower power once the room is cool. The DOE’s older label formula reflects this: it assumes inverter units average 0.5 of rated power and fixed-speed units 0.8.

Battery example (assumption labelled): a 1HP fixed-speed unit at 800W and an inverter unit at 740W, each for 6 hours.

• Fixed-speed: 800 × 6 × 0.8 = 3,840 Wh
• Inverter: 740 × 6 × 0.5 = 2,220 Wh

On a 4,096 Wh DELTA Pro 3 (3,482 Wh usable at our calculator’s 85%), the fixed-speed unit wouldn’t make it through 6 hours. The inverter unit would, with some to spare.

The label trap: “inverter grade” and “inverter class”

These aren’t DOE label categories. They can make a fixed-speed unit sound like an inverter one:

• Fujidenzo WAR-100IGT “Inverter Grade”: 800W, CSPF 3.34, 2 stars. Fujidenzo never claims an inverter compressor, and the specs match non-inverter units.
• Astron “Inverter Class” (e.g. TCL-60MA): Astron’s own site says the term refers to R-32 refrigerant “same used in inverter aircons”. It’s a fixed-speed unit.

Check the yellow DOE label and the spec sheet for “inverter” or “variable-speed”, and a CSPF figure, before you buy. A CLASP market survey found about 87% of window models on the market were non-inverter, so this matters most if you’re shopping for a window unit.

What to buy

• Inverter aircon: Kolin KA-100GQAIINV32 on Lazada · TCL TAC-11CSD/P7 on Lazada · Shopee · TCL TAC-09CSD/FBI on Lazada · Shopee
• Station with headroom: EcoFlow DELTA 3 Max on Shopee · Lazada
• For longer runs: EcoFlow DELTA Pro 3 on Lazada (EcoFlow PH) · Shopee

Check today’s price before you buy. Have the aircon installed by a licensed technician. Any connection to house wiring needs a licensed electrician.

Bottom line

On solar, choose a true inverter aircon, size the station for the top of its published power range, and ignore “inverter grade” or “inverter class” titles. For the wider comparison on the grid, see inverter vs non-inverter aircon.