This is a review of the iolloi zigbee ‘smart dimmer’. Amazon identifies it as ID-UK20FW09, and the iolloi.co.uk site lists it as ID-UK21FW09 (possibly the same product with a new SKU ID for the new year?). It’s marginally cheaper via Amazon at £32 per unit and is on prime.
Verdict: I really like this dimmer. Other than in looks, it outperforms a Lightwave RF in every way.
Context
I’m in the UK and have struggled to find good options for wall switch replacements. I started out with Aeotec in-wall dimmers but I like having control of brightness from the physical switch, and the space requirement meant some very tight wiring.
I now use Lightwave RF dimmers, which are easier and simpler, look great, and are reliable, but I’m falling out of love with them because:
- They need internet access to operate
- They require a proprietary hub
- The on-device dimming speed is not controllable and is VERY slow to react
- Super expensive! £60 for a 1-gang, £100 for 2-gang.
Recently I tried to buy some Samotech dimmers on Amazon and they were out of stock so Amazon recommended the iolloi instead, and I’d never heard of this and can’t find anything on it on the forums, but it was cheap so I bought one and so here we are.
Images
Comes in a simple cardboard box:
Zero stars for design effort but it looks credibly like a basic dimmer switch:
Wiring is incredibly easy - no neutral required. Back includes CE and Zigbee certifications, but no product name or code 
. It says it supports circuits of 5V-250V:
Performance
Putting it in discovery mode involves turning the light on and then double-press-and-hold the button until the light flashes. I found it was discovered by Home Assistant fairly quickly as ‘HZC dimmer’, and exposed a single light entity, which in my case was called light.hzc_dimmer_switch_zb3_0_level_on_off.
supported_features is 41, which based on this thread I take to mean that it supports transition, flash, and brightness. Lightwave’s dimmer’s supported_features value is 1, so it supports only brightness.
Sure enough, if I call service in developer tools and send a turn_on command with a transition time of 20s, the light fades to the target brightness over 20 seconds.
I have 4 5W LEDs hooked up to this circuit, and there is no noticeable flicker even at the minimum brightness.
Being a physical knob, you can walk up to the switch and twist it at any speed you like and the brightness of the lights tracks your action - as does the brightness level indicated in Home Assistant.
Conclusion
This thing is great. It’s half the price of the comparable Lightwave dimmer, and in comparison, it:
- is easier to wire, since it doesn’t require a neutral
- is easier to add to Home Assistant, because it is a native Zigbee 3.0 device, and doesn’t require its own hub
- does not require an internet connection to work
- supports transition time and flash as part of remote control commands from HA
- reflects its state in HA incredibly quickly
- has a physical twisty knob which allows very precise fading extremely quickly
- is easier for guests to use, because it behaves exactly like all the dumb dimmer switches they will be used to using in other houses.
There are some downsides. The main problems with it are:
- It doesn’t come in any finish other than basic white plastic, and doesn’t come in a 2-gang version (yet?)
- The fading is not perceptibly linear. I guess it’s probably linear in reality but I perceive little difference between 50% and 100% and lots between 0% and 20%. Lightwave has the same issue.
- There is a noticeable ‘step’ as it fades through low brightnesses. On a fast fade you don’t notice this but if you give it a transition time of 30s or something, you see it step-step-step-step through the fade.
For £32 a switch, I think this is great, and if they make multi-gang versions, I’d probably replace all my wall switches with these.
), unscrew the retaining bolt and remove the dimmer module from the panel. Typically the dimmer modules are interchangable in the UK. Its certainly what I intend to do with the one I just ordered…