There are various electric resistance package terminal air conditioning (PTAC) units. Electric resistance heating is a very expensive way to heating a building.
We recommend replacing the existing PTAC units with newer heat pump PTAC units. The heat pump PTACs will operate more efficiently down to about -5°C, at which time built-in electric resistance heating would be turned on.
Every suite will gain individual air conditioning.
Replace electric resistance heating units with equipment having the lowest practical energy cost.
Issues and Concerns
This retrofit puts more maintainable equipment (a refrigeration compressor and a fan) in each suite.
Use temperature bin method, with different heat pump efficiency within each bin. Eliminate savings below outside air low limit cutoff.
For Ontario climate, expect a long payback in the mid to high teens.