Steel will rust when it comes into contact with brass or copper. Hot and cold water
lines on top of the water heater are often made out of brass or copper. The
water heater's tank is made of steel. When they are connected together, the steel
tank rusts and weakens while the brass or copper connections do not rust at
all. Dielectric unions and plastic-lined nipples were invented to defeat this problem.
We will discuss plastic-lined nipples in this article. If your tank is
installed with copper only pipe nipples touching the steel tank, you should replace
them with plastic-lined nipples immediately. Don't panic though. Unless your
water heater is brand new and only a few months old, there won't be a damaging
corrosion problem. If you are handy with plumbing, you can install gate valves
on your hot and cold lines on top of your water heater. Use brass valves and
install them into plastic-lined nipples instead of directly into steel plumbing.
Do not install it to the steel plumbing directly or it will cause the steel
to rust. This will allow you to have positive control of your water lines at the
water heater itself. Heat traps can be used where the plastic-lined nipples are
installed. Hire a plumber to do this to increase the water heater's efficiency.
Make sure adapters are attached to the copper plumbing. If you have a combination
anode rod installed, the nipple you choose is very important as well. Install
a plastic-lined one if at all possible. If you have a curved dip tube installed
inside your water heater, you will need a three inch long plastic-lined
nipple as well. The easiest method of adding plastic-lined nipples if you have
steel plumbing is as follows: Attach to both the hot and cold lines a plastic-lined
nipple where the lines protrude from the wall. Attach to both of the hot and
cold lines another set of plastic-lined nipples where the lines connect to the
water heater. Use copper flex-connectors to connect the hot line from the wall
to the water heater and do the same for the cold line. Make sure to have heat
traps installed as well for increased heating efficiency. Plastic-lined nipples
may also be installed on the T&P valve. This keeps the T&P from getting any
trapped water inside and allows it to flow out of the T&P for your safety. This
is not essential, but it can help. |
