Mineral Deposits in Water Heater Inlet

While re-piping the cold water supply to my Water Heater, I noticed that at the the dielectric union at the water heater was very clogged with rust and other minerals. This would probably partly explain the terrible hot water pressure I get in my house. It was almost totally clogged with rust and black gunk. I cannot remove the Male portion of the Dielectric union (that is screwed into the top of the water heater tank), as its in their pretty tight. Is there any danger in simply taking a screwdriver and breaking up the mineral deposits so they fall into the water heater... or should I put more effort into replacing the nipple/dielectric on top of the water heater?

Thanks.

see attachments for some pictures to illustrate...

mineral deposits

Today I just charged someone $115 to come out
and use my "hi tech" craftmen screw driver and hammer to
rheem out the inlets like you are talking about...

a hammer and screwdriver work great to get
those deposits out of those nasty worthless dialectric unions.

its usually worse on the hot side ,....so do both

Great, thanks for the advice!

Funny thing is I already replaced the hot side and it actually looked cleaner than the cold. Must have been the black iron coupling someone had inexplicably joined with the galvanized pipe I just removed from the supply side.

Thanks!

Get an 18" or 24" pipewrench. remove the existing nipple and replace it with brass, or copper male adapter. If you have hard water, dielectrics act like a magnet for minerals and rust.

nipple

if the union and nipple are that bad, removing the crud will expose the surface of the pipe to the water, and it has probably started to rust and will turn your water red or brown. Replace it.