Is there a way to confirm that the heat pump is getting power? Ours stopped working (heating the floors like in a power outage). I suspected the breaker but that was ok. Is there a way to check that power is getting to the unit in the first place?

Did you turn the system off and back on? that would correct it if it were a simple lock out. There may be LED's on the circuit board, but you have to remove a service panel and be very careful as 230V is within.