During the listening process to identify the leak, we used bursts of compressed air into the line to listen for the area where the air escaped the pipe. We identified where the pipe entered the pool area from the control room, a series of 4-inch pipes feed the pool. Ultimately, we were able to hear the sound of the leak in a specific pipe by listening under the tile patio area and on the pipe itself in the control room.
When we did identify which pipe was producing the sound of a leak, we opened the pipe at the valve in the wall and inserted the Hand held Video Pro Camera with the Sonde Head to take a look at what was going on inside the pipe. We inspected the pipe from the wall up into the pool where the 4-inch line fed the trunk line to the pool. This was 60 feet of distance and we saw it all.
When we identified the break in the pipe, it was by snaking the pipe into the wall, where it took multiple short turns from the control room, through the concrete and into the pool area. At the first elbow, a long crack was evident and we inserted a mirror and dye tested the crack to back up what we saw, and in fact, it was leaking behind the wall, below the level of the pool area deck. Unnoticeable from the pool area, but clearly visible from inside the pipe.