So, I ran a Manual J calculation for a number of Portland, OR apartment units I’m renovating (2bdrm/1ba, ~750sqft each). All fall in the 12.5k-13.5kbtu range for heat load; closer to 9-11.5k for cooling loads depending on orientation. When I click over to the Manual S sizing calculator, it mentions Emergency loads of 10k minimum – 18k maximum. I’m not sure what exactly this means, and how it should affect sizing choice. Calc outputs are attached for reference.
We’re looking at Daikin LV-series DHPs, 1 per unit, with auxiliary cadet heaters in bedrooms and bathrooms. I’ve had one contractor suggest the 12k (this supplies 15k heat), and another suggest 15k (18k heat capacity). I’m not sure who’s right, or why.
Could somebody help me read between the lines? Given the way business tax credits work in the area, there’s a very small final impact on my bottom line — in fact it’s slightly less expensive overall to go with the larger units. I just want to make sure we’re making the right choice for occupant comfort and efficiency sake.

Thank you!