Attached are some pictures that show my current plumbing. I'm in the process of adding a heater, but am not sure the best way to tie it in. I don't see a way to cut the pipe and tie into anywhere. It needs to be plumbed to the outlet side of the return. Current PVC pipe is 2.5" which so far has further complicated the issue. I will most likely turn the filter 180 degrees and re-plumb my inlet to my filter from my pump, plumb in to my heat pump, and then connect back into my return line somehow. Just not sure how to do it once I take the union off where my filter connects to right now. Any ideas on best way to do this?