Stubborn Cold Water Inlet Leak

Old 07-30-10, 10:36 PM
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Stubborn Cold Water Inlet Leak

At the risk of embarassing myself, I was a partner in an HVAC
business for about 15 years. 95% of our work involved heating
and cooling, not water heaters. I should know how to fix this
problem because I've done a lot of plumbing. I feel like Porky
Pig when his head turns into a big lollipop that says, SUCKER!

My 50 gallon gas fired heater has a problem on the cold water
inlet side. The 3/4" copper for both the hot and cold side have
industrial quality unions, which makes it very easy to break
the connections. The unions are connected to stainless nipples
that are screwed into female fittings which are part of the tank.

The cold water inlet hole filled with water and started dripping
down the side of the tank. When I disconnected the union and
removed the nipple they both looked new. The fitting in the tank
is another story! I could see some of the threads had corrosion
and were damaged. I cleaned the fitting with some rust and
mineral disolver. I've seen countless threaded connectors in
this condition. I knew ordinary pipe thread compounds or various
PTFE tapes would not seal this leak. For decades I've successfully
sealed up couplings with damaged threads using a product called
Form-A-Gasket. When everything else failed, this stuff always
worked. It's widely available in any auto store.

When I turned the cold water isolation ball valve back on the inlet
hole immediately filled with water again. I starred off into space
for a few minutes in complete disbelief! I've probably used Form-A-
Gasket for over thirty years. I can't think of a time when it didn't seal
up moderately damaged threads.

If that female connector could be removed from the tank, it would
require special tools I don't have. They probably cost more than
the water heater. These water heaters may look rugged, but they're
not. Any massive power or hand tool designed to unscrew or drill
out that connector, would more than likely cause something else in
the tank to leak.

If I replace this water heater in another five years, I think I have
a reasonable solution that will outlast the life of the tank. Take a
new stainless nipple and use a high strength epoxy like slow curing
JB Weld.

If the coupler in the tank is replacable, I'll have to call a contractor
to do it for me. If I were still an active contractor, I would probably
charge $200.00 or more for this kind of repair. I got the heater at
cost for $350.00 from an old friend. He was my main supplier when
I worked at HVAC full time.

Any suggestions besides the epoxy would be much appreciated! If I
have to spend a lot to fix the darn thing, I might as well go with the
JB Weld.

Thanks guys.
Old 07-31-10, 12:10 AM
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They make HeliCoil repair kits for pipe threads.
Old 07-31-10, 03:00 PM
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Thank you ray2047.

I've used products very similar to the HeliCoil brand for
auto repair and in commercial heating and cooling equipment.

Here is the URL for HeliCoil:

Heli-Coil ( HeliCoil Inserts ) Helicoils Screw Thread Inserts |

The key words on this page that raise my blood pressure
are, "When they are installed into Heli-CoilŪ tapped holes."

I've gone to commercial and residential locations to install
or service central air systems and furnaces. When I arrive
someone would say, "by the way, we are having a little
trouble with our water heater." It's not uncommon to see
heaters twisted like pretzels when a breaker bar was used
in an attempt to extract a stuck anode rod. I wouldn't touch
an anode rod if I didn't have an impact wrench.

Drilling and tapping a new hole in a water heater scares me
a lot! Even if the tank is full, the unit is going to shake and
bounce like crazy. I've seen large and powerful men try to
steady a water heater while someone uses a breaker bar
or a drill. It doesn't work.

There are massive drills (1" chuck or larger) that produce
high torque at low RPMs. If I owned this type of drill I
might consider a HeliCoil. The key to working on a water
heater is to keep the vibration to an absolute minumum. If
you don't, a ticket to the junk yard is a sure bet.

I hope you can why I'm seriously considering a new stainless
nipple and some JB Weld. The nipple will easily last 15 years.
The heater might give another 5 years, if I'm lucky. Seems
logical, don't you think?

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