We received a call about a pool that had just had a new liner installed, but was still losing lots of water. The customer suspected the water loss was in the main drain line. When we arrived to the pool the Leakalyzer confirmed the reported water loss.
Solution
The main drain lines were plumbed separately up to the equipment, so we put an open plug in each of the main drains to see if they would draw dye. One line did, but the other did not. To confirm, we pressure tested the line that drew dye with water and it failed. In order to pinpoint the exact location of the leak, we then induced air into the line and began to listen with the hydrophone for a leak under the pool, but didn’t hear any significant noises. We then switched to using the Bigfoot microphone with the XLT30H to listen through the concrete around the pool and still didn’t hear anything that indicated the leak location. Only when we started using the XLT30H ground probes in the soil between the pool deck and the equipment were we able to get close enough to the leak to pick up a great noise and find the exact location of the leak.
Learnings
Thin ground probe rods included with the XLT30H make it possible to get the probe deep into ground to absorb leak sound vibrations.
Turning air pressure off and back on once hearing the leak location confirms the noise is the one we are making.
The customer noticed that a lot of sand was being blown into the pool and that there were bubbles in the air filter, so a problematic skimmer line was isolated and shut off. However, even after closing and plugging that problematic skimmer line there were still sand and bubbles being blown back into the pool.
Solution:
When we arrived to the pool, the skimmer line was plugged and a Leakalyzer test with the pump off showed no water loss. That made us suspect that at least the portion of the plumbing below water level was good. We then pressure tested the other two skimmer lines to confirm the whole line was good and they held pressure. The main drain was eliminated as the source of a problem without getting in the water through our Leakalyzer test that covered the plumbing below the water line and an air lock test that included the line that was above water level. Eliminating all of these other areas left us to examine the problematic skimmer line as the only potential problem. Upon further inspection, the valve used to shut off the line wasn’t holding, which explains the continued bubbles and sand in the pool even after the line was taken out of use.
To determine the specific location of the leak within the faulty skimmer line, we induced air into water saturated soil to listen with the XLT30. At first the bubbling and gurgling sound of a leak was faint, but just by turning the volume up on the XLT30 we were able to identify a distinct noise where the leak was. It was fairly easy tonarrow the leak location down to a 6’ diameter, but in order to get down to within 2’ of the leak we needed to use the advanced filtering capabilities of the XLT30. Once the high filter was turned on, there was a clear spot with the most distinct noise. As sound waves travel they get more and more muffled, so the sound will be crispest and most distinct right over the leak. The sound did fade a little as time went on, but re-saturating the soil by inducing more water into the line revitalized the sound.
The customer estimated that the skimmer line was 18” to 2’ deep, but when we cut the concrete and dug down to that level there wasn’t any moisture or pipe. To confirm we were in the right place we turned the pressure back on and still heard the leak so kept digging and finally found the broken pipe at just over 4’ deep. Before we replaced the cracked fitting we cut the pipe and pressure tested both ways to assure the rest of the line was good.
Learnings(are there any key takeaways or learnings from how this leak was found?):
Combining a Leakalyzer test with an air lock test of the main drain can confirm that line is solid without getting into the pool.
If you notice a once strong leak noise fading, you may just need to add more water to re-saturate the soil.
Trust your equipment! If you’re confident you heard a leak in a specific place, you may have to dig farther than expected to find it, but it will be there.
This job started as a request for us to run a vinyl liner scan with the LeakTrac because the customer had a leak that they suspected was in the liner in a swim ledge. So, when we arrived at the pool we did a scan of the liner, which showed the suspected swim ledge wasn’t actually a problem. The LeakTrac did locate a small leak on the vinyl stairs, but this leak didn’t draw enough dye to be the source of significant water loss. We quickly patched this leak with a Leakmaster Peel and Stick Patch before moving on to do a full leak detection.
Solution:
With a quick pressure test we found a skimmer line was not holding pressure. We then switched from inducing pressure with water to inducing pressure with air and heard a loud bubbling and gurgling sound right in the skimmer bowl without even using a listening device. The leak turned out to be a broken pipe just below the skimmer bowl.
To verify the rest of the line was good we dropped a 550 inflatable plug with an extension hose in past the leak and found the rest of the line held pressure.
A repair was scheduled for a later date, but before leaving the pool we plugged the skimmer line and ran a Leakalyzer test to confirm all leaks had been found.
Learnings:
Pressure testing is a quick way to isolate a pipe leak
Air escaping from leak in pipe makes a great noise for sonic location
The LeakTrac not only can be used to find leaks, but also to eliminate the liner as the location of a leak if no leaks are found
Customer told us that pool leaked down to 1” above the skimmer pretty quickly, then seemed to hold at that level.
Solution:
When we arrived at the job site we started our Leakalyzer test with the pump on which confirmed the water loss. After turning the pump off and marking the current test, we could see that the slope of the line continued to be the same as during the pump off test. Because of this we suspected a shell leak. Our observations of the pool equipment and plumbing system validated that the plumbing didn’t appear to be the problem.
Since a shell leak was suspected we began systematically dye testing the pool from the deck. By doing so we were able to find a crack in the skimmer bowl at the same level the customer indicated the pool water level held at. The size of the crack seemed consistent with what the customer and Leakalyzer indicated the water loss would be.
We then patched the skimmer with the Leakmaster Pool Glue Kit, which is adheres very well to the skimmer bowl and works underwater. After the patch we ran another Leakalyzer test to verify that the pool had stopped leaking. Although not as much as the first time, the test still showed water loss that was more than estimated evaporation.
With additional dye testing we quickly found another small leak in opposite skimmer. That leak was patched with Quick Set Putty.
We ran yet another Leakalyzer test and found the pool was losing less water than before, but still losing.
The water level was a little too turbulent after patching to get a great Leakalyzer test, but we spoke with the customer one week later and pool was not losing water.
Learnings:
The Leakalyzer helped us make sure all the leaks were found before leaving the job, instead of just finding the first one
Dye testing is really fast and effective
Gathering good information from the customer shortened the leak detection process
No information was provided prior to arriving at the job site, but when we arrived the water level was down to bottom of the skimmers and the customer confirmed that the water leaked down to that point and then stopped. A Leakalyzer test confirmed the water level had settled and was not dropping any farther. We established some suspect areas then put a hose in to fill the pool back up while we headed to our next job. We came back later once the water level was back up to finish the leak detection.
Solution:
When we returned to the job site, we confirmed the pool was indeed leaking with the Leakalyzer, then started to dye test the suspected areas along where the water line had settled. Not all suspected areas drew dye when the water level was raised, but we did locate two leaks in the corners where grout was gone from the tile line. We repaired the leaking areas with Quick Set Putty, then confirmed that the leaking areas were no longer drawing dye and that the pool water level had stabilized with the Leakalyzer.
Learnings:
It’s extremely helpful to know if the water level stops dropping at a certain point.
Pool water level needs to be at normal operating level to efficiently locate leaks.
Some leak detections are very straight forward!
Job also led to a sale of upgrades in pool filter.
Even though we stay busy making, selling and servicing equipment and supplies for the trade we make sure to regularly get into the field and find leaks to stay sharp and test products. Just recently we were called by a local pool professional who had a customer with an elusive leak and a long history of water loss in their pool. Two companies had been out before us with no success so we knew we were in for a challenge.
Background information from the customer:
Water loss dates back several years.
New liner installed last summer. Light was abandoned.
Customer was suspicious of steps but said it had been thoroughly dye tested with no results.
Was losing at least an inch per day and pool owner revealed it had lost 3/4″ in the 14 hours prior to our visit.
Previous companies had done pressure tests and everything passed as leak free.
Leakalyzer analyzes water level to provide valuable information.
The first task for us was to gather our own information so the Leakalyzer was set up promptly upon arrival. The Leakalyzer is able to measure water loss to the 10,000th of an inch. It quickly (5 mins) confirmed that we were losing an inch or more of water per day. The initial test was done with the pump on – the way the pool was when we arrived. We then did another test with the pump off. The leak was consistent regardless of whether the pump was running or not. Since we were losing an inch or more per day we knew we were looking for a significant leak. Our calculations brought us to around a quart per minute.
The next step was to dye test the fitting and stair gaskets then get the LeakTrac going. A Quick 10 minute sweep of the pool with The LeakTrac confirmed there were no leaks in the new liner. All the gaskets passed their dye tests.
Even though a pressure test had been performed by others we wanted to do our own to make sure. We had a hunch it was the main drain line so we started there and did an air lock test. It held right at 4.5 pounds of pressure (generated from 8 feet of water column). We then tested the skimmer and return lines and they held pressure too.
Now with all the lines plugged the Leakalyzer was still showing us that the pool was loosing over an inch per day. The leak seemed be someplace other than the plumbing and the liner.
LeakTrac locates a leak inside a stair return fitting.
We decided at that point to check with the LeakTrac one more time before getting into the pool to dye test the main drain. As we more thoroughly swept the pool one return was screaming louder than the others. The return in the stairs. This shouldn’t be since the stair return doesn’t have screws penetrating through the fitting and it currently had a nylon plug in it eliminating any distracting connection to ground through the equipment. We shouldn’t be getting a signal here but we were. The signal was not around the fitting but right next to the plug.
A dye test confirmed that water was escaping right past the plug that was sealing the threads.
We needed a mirror to fully see the problem when the plug was removed. Inside the top of the fitting was a small crack that was pulling a lot of dye.
The customer was happy we had finally found the problem.
Quick Notes / reminders from the job:
Following a systematic process of elimination helped zero in on the problem.
Leakalyzer helped us understand the true nature of the problem and confirm we stopped the leak once fixed.
LeakTrac helped us confirm the liner was OK and pinpointed the leak at the stair fitting.
For over 15 years this luxury pool located in downtown St. Paul, MN was left unused due to extensive leak issues that affected tenants three floors below the pool. This pool is located a top a luxury condominium tower and was completely drained due to the water damage it was causing. The pool is a beautiful 24 ft. X 44 ft. pool with “scum-gutter” skimmer system, but for the past few years tenets have grown angry that this relaxing spot has been completely unused.
Numerous easy to locate leaks were found and repaired. However, the skimmer system continued to leak aggressively when water was added to bring the water level above where the skimmer met the edge of the concrete pool. This leak was because the precast skimmer blocks that sat on the poured concrete pool had gaskets that deteriorated over time.
Quality Pools of Minnesota used Leakmaster™ Injection Foam from the Crack Repair Starter Kit to repair the leaks that extended around the perimeter of the pool. This product was chosen specifically because of its expandable nature. Injection Foam will expand 20 to 30 times its volume and force itself into all sorts of small cracks sealing them off from the backside of the pool. This closed cell foam is water proof and would help seal behind the gasket in spots that were not visible from the pool. This added waterproofing was extremely important due to the condo units below.
Small injection holes where drilled at apx. 1 foot intervals through the skimmer blocks. Injection ports where than attached to the surface using Leakmaster™ Peel-and-Seal Surface Seal Epoxy. Over 5 cases of foam was then injected through these ports to fill and seal the void beneath the blocks. Here are a few pictures that demonstrate how the non-water penetrating foam sealed even the smallest and most elusive of holes.
Small hole between skimmer and concrete pool
A series of large and small holes
Another elusive small hole
After injecting the foam and allowing it to set up, the injection ports were removed leaving little residue since the Seal-n-Peal product can be cleaned off with a putty knife.
After the foam residue was skimmed off the water’s surface, and a few cosmetic touches were made to the joint between block and wall this pool was back in use, saving the owner thousands of dollars in concrete repairs.
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