Custom: simple-thermostat

While the graphic representation of my thermostat ‘on time’ is very pretty, I have no idea what the rainbow of colors is representing. The resulting graph is the result of the hvac_action entity that has been further converted to hh:mm from the fractional hours result.

{{ state_attr( 'climate.pellet_stove', 'hvac_action' ) }}

{{ ( states('sensor.ps_heating' ) | float * 3600) | timestamp_custom('%H:%M ', false)  }}

HA ver 2021.12.3 on Docker

When a sensor’s value does not have a unit_of_measurement specified then the graph looks like in your case.
Specify a UoM → get a nice graph with curves.

Ahhh, I did not know that. Thanks for that.
I am not having any luck finding a suitable UoM for a time graph, however.

So you’re wanting to graph time over time? Not trying to be cynical, but what good is that? It seems like it would be much more interesting to graph literally anything else over time.

Graphing ‘on-time’ over time to be able to see difference s in ‘on-time’ from day to day.