Most of the PTAC units I’ve looked at in hotel rooms have had daylight visible right through them. And I can tell you from personal experience that the GE ZoneLine machines don’t even have the hot and cold sides insulated from each other, nor the outside world. There’s just a poxy plastic partition behind the blower wheel that’s got all holes in it for mounting various components, and since this slides out with the chassis this doesn’t seal against the inside of the sleeve in any way and usually leaves about a 1/4" gap around the top and sides. Maybe there’s some kind of boundary formed by air pressure when the thing is running, but when it’s off it absolutely allows outside air into the room without much hindrance. That’s before you get into fitment of whatever current unit is installed in the old-ass sleeve in the wall.
Even your $99 Walmart window unit has a big polystyrene block insulating the evaporator side from the condenser side (and thus also the outside).
Most of the PTAC units I’ve looked at in hotel rooms have had daylight visible right through them. And I can tell you from personal experience that the GE ZoneLine machines don’t even have the hot and cold sides insulated from each other, nor the outside world. There’s just a poxy plastic partition behind the blower wheel that’s got all holes in it for mounting various components, and since this slides out with the chassis this doesn’t seal against the inside of the sleeve in any way and usually leaves about a 1/4" gap around the top and sides. Maybe there’s some kind of boundary formed by air pressure when the thing is running, but when it’s off it absolutely allows outside air into the room without much hindrance. That’s before you get into fitment of whatever current unit is installed in the old-ass sleeve in the wall.
Even your $99 Walmart window unit has a big polystyrene block insulating the evaporator side from the condenser side (and thus also the outside).