INFRARED & ULTRASOUND DETECTION
FINDING UNDERGROUND LEAKS
A woman calls me and says that her water heater is leaking and wants
to know if I can find the leaks. Well I was thinking common water heater
and told her that she should be able to see the leaks around the pipes
along the side of the water heater, but she tells me that
all the pipes are under the floors in her house. That was the first
clue that we were not dealing with a standard water heater.
As it turns out, this was a slab built home, and the entire house was
heated with hot water with a radiant heating system. There were actually pipes running back and forth
under the floors of the house. These pipes were in
all the rooms and at the side of each bed and at the entry to each
shower. They didn't ever have to step onto a cold
floor; they were all heated with this array of piping that she was
referring to as a water heater.
Once I figured out what she was talking about, I told her we could
find the leaks in her “Water Heater.”
This water heater had several different branches that each
had a relief valve and a control valve. These control valves operated different rooms so that the rooms in use
could be heated and the rooms not in use could be shut down.
I ask how she knew that she had a leak, and she said that they had to
continually add water to the system. Normally,
the water should circulate through the system and then return for
reheating. The fact that they had to keep adding water meant that they
were losing water through a leak or several leaks. At this point we
started checking for the lines in the floors. It was very easy to see
the warmer lines in the floor indicating where the water pipes were.
After getting an idea of what we were looking at it seemed that if there
were a leak it should have a large plume at the leak because the water
would spread in the dirt around the pipes where it leaked and would show
This proved to be the case. We were able to find what appeared to be
several leaks in the system.
Notice how the line on the left appears much larger than the rest of
them. This was one of the first places we marked for a possible leak.
Moving on we were able to find other places that we were fairly
confident were leaking.
This one was also indicated by the stains on the tile floor.
This is a line in the hall way. We soon started to notice that it seemed
all these leaks were near a wall. We start to develop a suspicion that
the weight of the building and some settling over the years had a lot to
do with this problem. Along with the fact that it was black pipe that
was approximately 20 years old.
After we located what we were pretty sure all the locations that were
leaking we then pulled out the secret weapon, the Ultraprobe 10000. We
set the frequency at 20 Hz. We then went to an area that was known to be
leak-free. We checked there and set the sensitivity at a level that we
could just hear. We then asked her to pressure the system as much as she
dared to without causing more leaks. With one person holding the
camera and one person using the Ultraprobe 10000, we proceeded to try and
pinpoint the leaks. Using the camera as a guide to stay right on the
pipes we were able to hear the leaks through the tile and about 6” of
concrete. We went along the pipe and watched the DB levels rise as we
neared the place where the leak would be. When the level started down
again we knew we had passed the leak, so we'd backed up to where the Db
level was the highest and marked that spot as the best possible spot to
start checking for the leak. Knowing that the noise should be the
loudest at or near the actual leak, we were able to let them know where
to pull up the floor to fix the leaks.
We found that we were within 12” of all three leaks that were found.
They were repaired by taking up four tiles at each leak and breaking out
some concrete undermeath. After fixing the leak, the concrete and tiles were then replaced.
This home was a 4500 square foot home, and if they would have had to
pull all the floors to find these leaks, the costs would have been in the
$100,000 range. Using our technology, the leaks were repaired at a total cost of $7,000,
including the Infrared and Ultrasound costs.
This is a prime example of thinking outside of the box and using two
technologies together for a large money saving effort.
Needless to say these people were pretty happy.