Air leak question

[Sky1]

I wondered if anyone could answer this one for me , can underground pipes leak air in ? I can’t work out how a possible fracture on a main drain pipe that’s 9 ft underground can leak air in . I assume any air on the suction side getting sucked in has to be above ground level .

[Teapot]

Annoyingly they seems to, depends on soil type I would imagine, clay being quite good at being air tight. You would have to be sure the leak was at the depth you say and not somewhere else on that line. A Pro with a hydrophone could pinpoint a leak by listening for the bubbling noise caused by an air leak.

[Sky1]

Thanks for replying , i belive its higher , underneath the slabs , years of water washing out the pionting. So another question what pointing is best to use thats doesnt fall to pieces with chlorine , i think i may use a resin based one , as constant use of pool and dripping chlorine kills the cement pointing in my opinion .

Im going to run skimmer only the pool doesnt need draining , the spider gasket has also had it so thats next port of call , i used gas leak spray on all joints in pump area and none got sucked in re the air leak .

[Teapot]

You only need the skimmers, main drains do virtually nothing. All dirt enters from the surface so that is the best place to remove it.

I use external tile grouting around the pools, water proof although a little more expensive it lasts well.