The way I pressure tested:
Cap the return at the pool (real well). Open the return line somewhere after the filter (my returns have unions right after my SWG).
From Home Depot, you can get a pressure testing cap. Mine is for 2" pipe, is red, has a rubber gasket and an air filler (like on a tire) that has a wing nut on one side and a big washer on the other. They normally are on the very bottom shelf - only cost about 5 bucks. It fits in the open end of the pipe. You tighten down on the wing nut to seal it in, then use a compressor or tire pump to pressurize the line. BE REALLY CAREFUL, my pressure cap blew out several times before I could get it well seated. I would recommend duct taping it just to be safe.
If the line is leaking, the air pressure will drop (obviously). But, what worked for me (inadvertantly!!) - we had water in the line and where the air was escaping we could hear bubbling and gurgling, even through the concrete.
Cap the return at the pool (real well). Open the return line somewhere after the filter (my returns have unions right after my SWG).
From Home Depot, you can get a pressure testing cap. Mine is for 2" pipe, is red, has a rubber gasket and an air filler (like on a tire) that has a wing nut on one side and a big washer on the other. They normally are on the very bottom shelf - only cost about 5 bucks. It fits in the open end of the pipe. You tighten down on the wing nut to seal it in, then use a compressor or tire pump to pressurize the line. BE REALLY CAREFUL, my pressure cap blew out several times before I could get it well seated. I would recommend duct taping it just to be safe.
If the line is leaking, the air pressure will drop (obviously). But, what worked for me (inadvertantly!!) - we had water in the line and where the air was escaping we could hear bubbling and gurgling, even through the concrete.