# Dreame L40s Ultra CE review

Lowest cost L40s with auto empty and mop washing

- Our score: not scored yet
- Price: $470 (checked Oct 31, 2026)
- Status: on sale
- Best for: first time buyers who want a full dock cheaply
- Skip if: you have pets, clutter or want hot water mop washing
- HTML version: https://robotsforthat.com/robot/dreame-l40s-ultra-ce/

## Verdict

A cheap way into a self emptying, mop washing dock with long runtime. Vacuum Wars found good carpet cleaning and no hair tangles, but weak pet hair pickup, poor obstacle avoidance and wet mopping. Spend more on the L40s Ultra or AE if you have pets or clutter.

## Pros

- Low price for a full dock
- 89% carpet sand removal
- No hair wrap with TriCut brush
- Long claimed runtime
- LiDAR mapping

## Cons

- Avoided only 8 of 24 obstacles
- 68% pet hair pickup
- Leaves the most water of the L40s range
- Cool water mop wash only
- Detergent dosing costs extra

## Specs

- suction: 13,000 Pa on the Dreame product page and comparison blog
- navigation: LDS LiDAR with Smart Pathfinder (Dreame); Vacuum Wars measured 0.73 m2 per minute
- obstacle avoidance: Single laser 3DAdapt structured light, no camera (Dreame); Vacuum Wars saw it avoid 8 of 24 objects
- mopping: Dual spinning mops with RoboSwing, 10.5 mm lift, no extension or auto removal (Dreame); Vacuum Wars measured 2.20 g water left, the most of the L40s range
- self empty: Yes, 3.2 L dust bag, up to 100 days (Dreame)
- dock features: Auto empty, cool water mop wash, warm air drying, auto water refill, 4.5 L clean and 4 L used tanks; auto detergent dosing is a $39.99 add on (Dreame)
- runtime: Up to 260 min in quiet vacuum mode from 5,200 mAh (Dreame); Vacuum Wars estimated about 1,922 sq ft per charge
- dustbin: 300 ml or more plus 3.2 L dock bag (Dreame)
- height: 104 mm (about 4.1 in) (Dreame)
- pet hair: TriCut Brush 3.0 (Dreame); Vacuum Wars measured 68% pet hair pickup, 89% carpet sand removal and 0% hair wrap
- app: Dreamehome app with Alexa, Siri and Google Home through third party devices, no built in voice (Dreame)
- threshold: 20 mm (Dreame product page); Dreame's comparison blog lists 22 mm in one section and 20 mm in another

## Safety

- recalls: Not checked
- fcc: Not checked
- company status: Active
- warranty: 3 years (Dreame US store)

## Questions buyers ask

### Does the dock wash mops with hot water?

No. Vacuum Wars says the CE uses cold water to wash pads, then dries them with warm air.

### Will it add detergent automatically?

Only with the $39.99 auto solution dosing accessory, sold separately.

### How long does it run?

Dreame claims up to 260 min in quiet vacuum mode. Vacuum Wars estimated about 1,922 sq ft per charge.

## Sources

1. [Dreame US store: L40s Ultra CE](https://www.dreametech.com/products/l40s-ultra-ce-robot-vacuum)
2. [Vacuum Wars: Dreame L40s series review](https://vacuumwars.com/dreame-l40s-series-review/)
3. [The Smart Home Hookup: Dreame L40S Ultra CE](https://www.thesmarthomehookup.com/?p=10269)
4. [Dreame newsroom: L40s series launch](https://www.dreametech.com/blogs/news/dreame-l40s-series-robot-vacuum-launch)
5. [Dreame blog: L40 Ultra Gen2 vs L40s Ultra vs AE vs CE](https://www.dreametech.com/blogs/blog/robot-vacuum-comparison-l40-l40s-ultra-ae-ce)