Leak Test Condition 5

Leak condition 5 refers to the pool leaking when the plumbing system is off, and not leaking when the plumbing system is on

leaking pool pump

Similar to condition 3 if your pool is leaking when the pump is off but seems to improve or stop leaking altogether when the pump is turned on it is very likely you have a suction line leak somewhere in your system.

Symptoms Of Suction Leaks

The suction of the pool pump running can actually pull closed a small leak in a suction line. This creates the potentially confusing situation where the pool leaks when turned off but holds water levels when the pump is running. This should also result in problems priming the pool pump or air being pulled into the system where it is visible in the pump strainer.

Burning Out Pump Motors

A common symptom of suction line leaks in swimming pools is to experience an unusually high rate of failure for your pool pump. This is specifically true for pumps located above the level of the water in the pool where it will need to work harder to lift the water uphill.

Air in the plumbing system will cause the pump to overwork or potentially lose prime altogether. This can result in overheating of the pump motor and windings which will eventually short the thermal disconnect in the pump but sometimes not before permanent damage is done. If the pump is burned out because of overheating then you will likely find it with the electrical breaker tripped. Turning it on will result in some noise and then breaker will trip again as the pump will require motor repair or replacement.

Potential Leak Locations

Based upon the leak characteristics displayed by your swimming pool during the hydrostatic leak test, here is a list of the more likely areas of concern for your pool. This information is not sufficient for stand alone diagnosis of your swimming pool leak in most cases, but can very often lead to an efficient diagnosis and repair due to recurring instances of these common pool failures:

(small leak of less than 1” / 2.5cm per day)
-Crack in skimmer suction line or fittings

(medium leak of 1-3” / 2.5-7.5cm per day)
-Crack in skimmer suction line or fittings
-Crack in the main drain suction line

(large leak of more than 3” / 7.5cm per day)
-Broken suction line or fitting

You can read more about this condition and suction leaks before continuing to the next leak test the water level test

The menu on the right is a chronological step by step process to determine where a swimming pool is leaking. This website is written as a readthrough technical assistance guide for locating leaks. When you believe you have identified where the pool is leaking you need to go to our sister website to see pictures and learn more about the actual swimming pool leak repair process.