Nate Adams asked whether the heat pump was modulating its electric use to maintain temperature or cycling on and off? The power data (below) show it is cycling on and off.

The graphs below are for the last 30 hours or so and overlap with some of the data I posted yesterday. They also include another night of heating with the 18 kBtu/h heat pump. The first graph is what Home Assistant gets from the Mitsubishi Kumo Cloud interface regarding the settings of the heat pump. The second graph is the Govee temperature data and the third is electric power from both the heat pump (blue) and the electric heaters (purple).

For most of this time I am heating with the heat pump. In early afternoon (2-4PM) solar gain through the windows causes the Govee temperature to rise above set point and the heat pump throttles back. The HP was turned off from 4-8AM yesterday to heat for 2 hours with electric then 2 hours with propane. The electric heater power data are shown in purple.

The first graph clearly shows that the set point (purple) is 63F while the measured temperature of the wireless sensor (blue) bounces between 64 and 65. I simply do not understand why the Mitsubishi control software maintains an average temperature above the set point.