Sorry for the delay. Here is the name plate info.. The unit is CPheater052A
After looking at the label, I'm not sure what the confusion is about???
The 8th column (Fuse or HACR breakerper NEC) says 45/45 (if that's your heater). So that's that. 45A
Not sure why the MCA is 44.9A(20.8A for the heater times 125%=26-27A, plus 5-6 Amps at the most for the motors, it's only about 31-33), but that's what the manufacturer is specifying.
Allthough if you consider the permissible voltage allowed, then you have about 24A*125% for the heater=30, plus another 5-6 for the motors, it gets close.
Not gonna do the exact math, but it seems the MCA is the heater at 125% and all the motors(including the compressor) at 125%. Not sure why they did the as the compressor and the heater SHOULD be non concurrent loads. However, I have seen AC's who use the heater to dry the air at the same time the compressor is running, so that may be your answer.