Cleaner lines are not all the same -- suction, pressure, and booster-pump lines each require a different isolation approach before the gauge means anything.
Learn the H.U.N.T.E.R. Method →A cleaner line is pressure tested by first identifying whether it is a suction line, pressure-side line, or booster-pump line -- then plugging the cleaner wall fitting, isolating the correct equipment-side connection, applying controlled pressure, and watching the gauge. Booster-pump systems must be isolated at the booster discharge side so pressure does not bleed through the pump, check valve, or union. A pressure drop must be checked against the plug, cleaner valve, booster plumbing, and test setup before the underground pipe is called bad.
A cleaner line test cannot be set up correctly until the technician knows which type of cleaner system is present. These systems are not interchangeable in their testing approach.
Connects to the skimmer or a dedicated suction port. Water is pulled back to the pump. A break may cause the pump to pull air. Tested like a suction line -- conservative pressure.
Taps off the return side and delivers pressurized water to the cleaner wall fitting. A break may cause loss when the pump runs. Tested like a return line after isolation.
A separate booster pump drives a pressure cleaner. The circuit has its own plumbing, check valves, unions, and quick-disconnects. Must be isolated at the booster discharge side -- not just the wall fitting.
Some older cleaner lines are no longer active or were repurposed as returns or capped. Document what the line currently does -- not what it was originally designed for.
This is the most common mistake in cleaner line testing. If a booster pump is present and the technician only plugs the wall fitting without isolating the booster discharge side, pressure will bleed back through the booster pump, check valve, or union -- and the gauge will drop regardless of whether the underground pipe has any problem.
For booster-pump systems, the technician must disconnect or isolate the booster pump from the test circuit. This may mean disconnecting at the union, isolating with a valve on the discharge side, or removing the quick-disconnect fitting. The exact approach depends on how the booster plumbing is configured.
Determine whether the cleaner line is suction-side, pressure-side, or booster-pump driven. Confirm whether the line is still active or has been abandoned or repurposed. This step determines how the rest of the test is set up.
Turn the pump off. Remove quick-disconnect fittings or cleaner adapters. Dye test the cleaner wall fitting face, fitting-to-shell joint, gasket, and screw holes in still water. Confirm whether the fitting itself is leaking before testing the pipe.
Use the correctly sized plug for the cleaner wall fitting. Confirm it is fully seated. For suction cleaner lines, verify the cleaner port connection is plugged -- not just the eyeball or directional nozzle.
Close the cleaner valve at the pad. For booster-pump systems, also isolate or disconnect the booster pump from the test circuit at the discharge union or appropriate connection point. The booster pump, check valve, and any quick-disconnect must not be in the pressurized test circuit unless they are specifically being tested.
Connect the test rig and gauge. Apply controlled pressure appropriate for the line type. Note starting pressure. Monitor the gauge. The test window should be long enough to detect a real leak -- not just a brief gauge check.
Use acoustic tools, trace gas, or pipe camera to locate the underground failure. Repair the confirmed break. Pressure test again. Document starting PSI, ending PSI, plug location, and test duration.
Ask when water loss happens -- only when the cleaner runs? Only with the booster on? This identifies which circuit to test.
Identify whether the cleaner is suction, pressure, or booster-pump driven. Note check valves, unions, quick-disconnects, and current vs. original use of the line.
Dye test the wall fitting first. Use operating behavior to confirm which circuit is involved. Confirm the line is still active before testing it.
Plug the wall fitting, isolate at the pad including the booster discharge if present, apply controlled pressure, and verify the setup if the gauge drops.
Confirm line failure after setup verification. Use a locating tool to find the underground break before recommending demolition.
Repair the confirmed source. Retest. Document all results including plug location, booster isolation method, PSI, and duration.
Plugs the wall fitting, doesn't isolate the booster pump, gauge drops, calls the underground pipe broken. The gauge dropped because pressure bled through the booster pump -- not because the pipe was bad.
Identifies the cleaner system type before touching a plug. Isolates the booster discharge before testing. Dye tests the wall fitting separately from the pipe. Verifies the setup completely before recording a result.
Jeff David is the founder of Leak Business Academy, LLC and Leak and Subsurface Locators, LLC. He is a licensed pool contractor in Florida and an FSPA Palm Beach board member. Jeff teaches the H.U.N.T.E.R. Method -- including why cleaner line testing requires the technician to identify the system type first, and why booster pump isolation is the step most technicians miss when a gauge drop falsely suggests a broken underground pipe.
LBA training covers suction lines, return lines, cleaner lines, and booster-pump circuits -- with the exact isolation protocol, pressure selection, and documentation approach for each.
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