elcraft; Not quite really. Let me add to to expand the post.
The paste dielectric compound would not be acceptable for the plumbing connections of a hot water heater. It would fail inspection. The code required items are called dielectric couplers, one for each line. About $5 a pair at any home or hardware store. They are about 3-4 inches long and screw into the threaded fittings on the tank. Then the plumbing lines (typically copper) connect to them. These couplers have a non-conducting center section and a vinyl lining which prevents the electrons from flowing between the dissembler metals (which is what used to cause the iron tank to rust out on the inside and burst during thermal cycling). The paste will not prevent the two different metals from touching and thus worthless for that use. Refer to the US Residential House code. I think this standard kicked in about 1985 or so, mostly due to pressure from insurance companies who were getting killed by water damage claims. There may be a use for the paste in a electric water heater such as on the wiring connections to the heating element (which it would be for as found near water heaters in the store).
The intended use for the paste DiE is for the electrical connections such as those you mention; Any connection exposed to weather or water/moisture and is awesome for the threads or pins of any light bulb anywhere, trailer connector, cable and satellite antenna, etc. I believe there is a slightly different compound required for boats, airplanes, etc.
Yes agreed, nice stuff. I always have tubes of it in my tool bags.
Originally Posted by
elcraft
This compound is used in plumbing connections, especially water heaters. Where the steel connector joins with copper pipe, electrolytic corrosion occurs more dramatically. You can find this in the plumbing section of your home center, usually next to the water heaters. I use it for electrical connections that are exposed to weather, as in an automobile. Nice stuff!