You likely need to calibrate the brightness levels within the Kasa app. With the Kasa app opened, go to devices, then tap on the name of the HS220. Go into device settings (top right icon), and scroll down to the Advanced section, and select "Dimming Calibration". Set your desired brightness levels in that menu.

I have a related issue. I would like to decrease the brightness level at the lowest dimmer setting. I have used the Dimming Calibration but the lights never dimmed as much as I wanted them to. It never got to the point where they would flicker or cut out. Some advice would be appreciated.

Similar issue: just installed the HS220, and it connects fine to network and turns off and on through the network, but zero dimming effect with LED load. Full bright all the time. What's up with that?

@Andreww What is the firmware version you are currently running with the smart switch?

@mooneysmith What is the model of the LED bulbs you are using?

Firmware version 1.5.7

@BigJoe I just bought an hs-220 and I have exactly this same problem.

When installing, when disconnected from the internet, the dimmer had a way lower range (like my previous non-smart one), which is what I like. As soon as connected, the lowest setting is way brighter than the lowest setting when not connected (I'd say the range is about 40% to 100% only).

Is there any fix for this?

EDIT: Just fixed it.

1) Remove the dimmer from the Kasa app, it will disconnect from the internet

2) Go to the dimmer, turn it on and manually set it to the lowest setting. You'll see that it goes low enough.

3) Keep it in the lowest setting and add the device back to Kasa app. 

4) Do the calibration and this time it will access the correct range.

I guess it failed the first time during instalation because the firmware wasn't updated yet.

@BigJoe It isn't Intuitively obvious, but the calibration occurs within the app itself under the device settings - calibration. When in the calibration mode, the slider is not an up and down slider, but a tap on top or tap on bottom of the "slider" depiction/control to make the light brightness go up or down. Again, this calibration is performed within the app.

@skyb It is about dimming possibility for low level light.

I have dimmable LEDs, and without Kasa app I can go down to real 1%. But with app when I adding the device, the minimum level is jumping after calibration to 25%, it is no difference between 1% and 25% anymore. I cannot get the REAL 1% of the brightness with the app.. It is software and how to fix it?