Originally Posted by Ko_deZ
You are quite right. Parallel is better. The reason is simply that you avoid having possibly a full HX freeze up.
Thanks Ko_deZ, this is what I suspected. Since for this first test I'm going to avoid breaking the seal, I'm just using the evap built into the window A/C. To try to delay freeze-up and add efficiency I plan to build an adapter out of sheet metal so I can have both the blower from the working A/C and the one from the A/C that lost it's refrigerant pulling air through the coil. My hope is the extra ari flow will keep the coil temp a little higher and stave off freeze ups so I have to do less defrosting.
I have another question though, I'm going to be running in temps between 30*-40*F, and trying to keep the hottub at least 102*F, will my heat pump even be able to achieve that Delta T?