Water heater leak (cold side only) where the nipple meets the water heater
I just bought a water heater and completely installed it. When I turned on the water supply, a very very very slow drip can be observed where the cold water nipple screws into the water heater. I shut off the water, relieved the pressure and unscrewed the nipple. I then re-apply the teflon tape to both ends (about 4 passes) and flipped it just to see if it would leak for the top this time (this would indicate a thread problem in the nipple. I re-installed the nipple with a pipe wrench, making sure it was snug (not too tight and not too loose). I started the water again and the same very very slow water accumulation could be seen at the cold water entry point on the top of the water heater. The other nipple coming from the hot side is completely dry, and I used the same procedure when installling. So is it the nipple, or is it the water heater threads or something else. Thanks!