Pictures may be needed later, but let me see if I can start the ball rolling...
The ancient heat pump I have seems to have seen its last day. The blades are all askew, what holds it at the top to the grill is all rusted out and barely hanging on. It was working till I turned it on yesterday and did nothing (I don't think it's a power/fuse/breaker issue). The rest of the unit does not seem to be in much better shape.
(1a) Spend $3k and replace the whole thing with something presumably more energy efficient. Maybe even take advantage of that and do some replumbing (dual/variable speed pump? SWG?)...
(1b) Go solar - definitely will need some replumbing and addressing of issues: got the south-facing roof, at least 100sq ft, but (a) hurricanes/roofing code and (b) an eave that juts out about 18-24 inches which may make a pipe to the roof quite unsightly.
(2) Figuring that the coils/innards are in working order since I used it last week, replace the motor/blades. It looks like the top grill can be unscrewed and that whole assembly comes off - just needs to be plugged in to the rest of the unit. Problem with this: I have no idea what make/model I have (can't make anything out other than 85-1A or 85-18). Also, what defines the efficiency - that motor (which consumes electricity), the coils (which do the warming), or a combination?
If #2 is a $100-200 fix, great... otherwise, my water will remain cold until summer while I figure out best way to handle and wait for the money tree in my back yard to bloom.
Preliminary thoughts (pending some day that I can take a picture during the daytime - either pre-work or weekend).