Just bought a new Sears hot water tank. Blue insert inside cold water nipple sticks up 1/4". Can't get it to sit down flush with top of nipple. Any ideas?

Can you show us a picture?

Sounds like a plug to keep dirt out when in transit.

Chuck

Hi Kwag

That is the plastic that makes a dielectric nipple (supplied with all water heaters nowadays) non-conducting. Here, if the nipples didn't have this plastic insert the dissimilar metals between the tank tappings (steel) and the nipples (metal alloy) would create an electrolytic effect that would cause a deposit of minerals at the nipple that would close the nipple down and reduce volume of water delivered to the house.

I am guessing that the issue you are having is to tighten the new copper fitting onto this nipple, yes? If so, be patient, wrap some teflon tape and/or pipe dope on the nipple, PRE-SOLDER your fitting onto pipe (let it cool) and then get it threaded onto the nipple being careful NOT to cross thread, OK?

Back to you...

Mark