Customer had a leak in the crawlspace coming from a drain separation where the drain connects to the waste and overflow of the tub. Also noted to customer that the water heater was 16 years old and needed replacement. Replaced the water heater with a new Rheem 50 gas, shutoff, pan, and thermal expansion tank. Replaced the leaking cast with new pvc. Connected to the 45 coming off the 3x2 tee on the cast and reconnected to the existing cap waste and overflow. Made a not that there appeared to be condensate on the bottom of the tub drain, it didn’t appear to be a drain leak. Left quote to replace the waste and overflow in the event there’s any issues with it due to the age. Tested all work to ensure proper functioning and no leaks. None were found. House pressure at 75 psi with new thermal expansion tank.