ckwjl wrote:
It looks like the nipple at the cold water inlet of your water heater snapped. This nipple is a threaded check valve made of black plastic. The hot water outlet also has one, just turned in the opposite direction. My hot water outlet check valve cracked and I broke it completely off trying to remove it with a wrench. Get a $9.50 Pipe Nipple Extractor Set HDX167 at Home Depot. Harbor Freight has a similar set. Getting the check valve out with this is a breeze. I replaced the plastic check valve with a brass one I found at my local RV supply store.
This was exactly it. And that extractor worked great. Now to piece together the PEX from the bypass valve to make sure this doesn't happen again.