What is this ??

Could any any one please tell me what this. It was on the outside wall behind the condensing unit


IMG_0334 (Small).JPG

IMG_0336 (Small).JPG

IMG_0337 (Small).JPG

That appears to be a heat recovery system to supplement the water heater. Works by capturing excess or available heat from the a/c system when it is in use.

Thank you Micheal, that is exactly what I thought it was (NOT!!)
I have never seen one before

I’ve seen a few in my area and will see if I can find a more descriptive site for reference. Try: http://www.heatharvester.com/Heat_Rcovery_System.htm