PTACs for heating and cooling

PTACs are a huge pain and one of the worst parts of Manhattan living. Modern reversible heat pumps are a far better way to go.

Ideal is to do a mini-split system heat pump with the compressor on the roof or ground or even mounted to the facade and a condenser unit inside. It heats in winter and reverses at the touch of a button to cool in summer. They are the most every efficient systems that don't involve geothermal.

https://www.homedepot.com/b/Heating-Venting-Cooling-Ductless-Mini-Splits-Mini-Split-Heat-Pumps-ACs/N-5yc1vZ1z18ggk

If not, do something like this:

https://bestchoiceproducts.com/products/4-in-1-14-000-btu-portable-air-conditioner-cooling-heating-unit-w-remote

*energy efficient

If it is landmarked, will you be able to make a hole on the wall for PTAc unit? Usually 12x12 inch min is needed. Also electric heating bill will be pretty high vs if you have gas powered boiler. Cost is only $1500 Per unit plus making a hole in the wall (that can be 1k min plus facade repair) plus wooden covers if you need them. You also need to check if you have sufficient power / meter capacity in your apartment for heating and if you have 220V power supply where you plan to put ptac units.

You can get PTAC with heat pumps.

PTACs are great for bringing that motel feeling to your home.

The premise of your question appears to perhaps be faulty, as 300_M points out. Even apart from your building, there is no way landmarks will let you cut a hole in a landmarked facade to feed the PTAC. And, typically the holes are much larger than 12x12, but more like 2'x3'. They are ugly, horribly inefficient, loud and mostly of poor quality. If you have any ability to put a compressor on a roof or in an alley, the minisplit is a vastly better solution (but getting rid of your boiler would be a bad idea)

Sport, there are some 12-14 inch deep and tall PTAC which only need a small wall sleeve for ventilation (Siminaire, Iceaire, Adirondack may make them). These are most common in Manhattan post war building and need a small cutout for ventilation as the unit itself does not go in the wall but against the wall.

12-14 inch deep but tall.