What could be the reason why some «heater» devices which definitively have «climate excluded» set to «false», according to the Homey dev tools, are still not included in the total Climate number or the Climate overview window?
Can you give a example of a brand/Device type and on what Homey model and Mobile App?
I guess if someone can reproduce it it is an issue to notify Athom Support
It’s a MQTT Hub virtual device, but I wouldn’t think that would matter. I assume device class «heater» is applicable to Climate inclusion anyway. Especially since it apparently has the «climate excluded» property (and set to false by default), as well as a «measure_temperature» capability (amongst others).
Are there other requirements?
If I make a similar virtual device with class «thermostat» it is accounted for under Climate.
My Homey is an updated Pro 2023 and I have a fully updated mobile app too.
What happens when you set it to true?
It gets superexcluded from Climate, in a manner like Napoleon to the barren island of St.Helena…? 
No, seriously, I assume you are thinking of then setting it to false again, and see if that active change sets something in motion?
I will have to try that by an API call when home later, as the (MQTT Hub virtual device) UI unusually has no setting for it.
There should be an Setting in the Device Advanced Settings by default …
If that isn’t there it is probably the wrong Capabilities? Tutorial: Device Capabilities - Homey Apps SDK v3
No API Tinkering necessary…
Please show some screens you are referring too, as I am lost.
The “Exclude from climate” is in the advanced settings of the device. It is easy to change and I would expect to see something changing in the climate group. As it changes from included to excluded.
