Two pool leaks traced with a hydrophone in Dunstable
A home swimming pool was losing water, and faster when the pump was running. A hydrophone in the skimmer pot picked up leak noise, and the investigation found a cracked skimmer body and a cracked glued joint in the filtration pipework.
Signs of the leak in Dunstable
The pool was losing water, and the drop was worse while the pool was running. The water was at 19 degrees. The returns outlet sits inside the body of the filtration unit, so it could not be reached directly for testing.
How acoustic equipment found it
The engineer first listened across the pool circuit, and the acoustic readings pointed to the area around the filtration unit. A hydrophone lowered into the skimmer pot then picked up clear leak noise, which directed the search to the skimmer body. Dye and pressure tests then confirmed the crack there and showed a second leak further along the same line.
The investigation, step by step
- 01Checked the pool and the filtration unit, and noted that the returns outlet could not be reached for testing.
- 02Listened across the pool circuit, which pointed to the area around the filtration unit.
- 03Lowered a hydrophone into the skimmer pot and heard clear leak noise.
- 04Put dye in at the skimmer outlet and watched it being drawn into a crack in the skimmer body.
- 05Pressure tested the skimmer pipe, which failed. With a bung placed past the crack the line still dropped, more slowly, showing a second leak.
- 06Inspected the filtration pipework and found a cracked glued joint where the pool pipe changes to mains fittings at the pump union.
- 07Cut out and replaced the cracked filtration pipework, and sealed the skimmer crack with epoxy resin putty.
What was found
- Found
- Two leaks: a crack in the body of the skimmer outlet, and a cracked glued joint in the filtration pipework where the pool pipe connects through a union to the pump. That pipe was under tension and about one inch out of line.
- Repair
- The cracked filtration section was cut out and replaced with new PVC-U pipe, fittings, an elbow and a union, correctly aligned. The skimmer crack was given a semi-permanent repair with epoxy resin putty.
- Recommended afterwards
- Keep an eye on the returns pipework. If the putty on the skimmer needs more work, the fallback is to repair or relocate the skimmer outlet, which would take at least a day on site and may need digging.
- Worth knowing
- The skimmer repair is semi-permanent: the crack sits deep in a tight space, which limited how much putty could be applied. The returns outlet is inside the filtration unit, so the test bung could not be confirmed as fully inserted there, and a crack at that point could have been hidden.
