I've contacted Sense about this twice and both times was told to just wait and Sense should find it, but it isn't happening.
I have a basic gas furnace, with an exhaust blower and the main circulation blower. When I originally installed Sense, after a few weeks it detected a device that was related to this furnace. We were right inbetween running as AC and Heating, so the exhaust blower may not have been always running along with the circulation fan. Sense saw it as ~800 watts when running.
About 2 months ago, the device stayed the same name, but only started seeing it as 93 watts and I confirmed it was only detecting the exhaust blower that starts a few seconds before the circulation blower while things heat up. The 636 watts of the circulation blower are not detected as part of any device and impact the Unknown number only. It has a distinct jump when starting, and since it runs at a separate time, I don't understand why Sense hasn't detected it either as part of the existing device like it did, or as a separate device which would be preferred.
Support just says to wait, but 2 months is long enough as it cycles many times a day and has the same pattern, and it is a standard motor, nothing fancy like multi-speed etc.
Especially frustrating as it was included, then the signature differentiated enough to not be included in the existing device, but never seen as a new device.