First time question asker, here. I have read several threads on this site, which is a great resource. I am still unsure if what I'd like to do is safely possible, so here I am asking about my specific situation.
I have a dead pool heater (electric heat pump) that I'm not going to replace. It is serviced with 8/2 wire (white, black, and bare ground) and already has a 50A two pole breaker on the main panel. The service on the back of the house is a great location for me to convert the circuit for either of the following uses, both of which would be better than having an unused circuit.
Option 1. Install a twist lock inlet (L14-20P) so that I can backfeed the panel via a 5,000 watt generator for occasional use. I would use an interlock kit to do this correctly. My question is, as the generator has a 4 prong outlet (L14-20R), is it possible to safely connect to the 3 wire? What to do with the ground and neutral? My generator has a floating neutral. The neutral vs ground - and where that all occurs - is what makes my head spin.
Option 2. Install a 50A RV service, which would also be for occasional, short-term use. Same question, since the NEMA 14-50R is designed for 4 wire (X,Y,neutral, and ground,) can I safely make this work with the 3 wire?
Other details that might matter. There is a manual disconnect box in line for the heat pump that I could either keep or remove. I am in FL.
Any help is appreciated. Thanks!