Using 4 steel radiator like bands, I replaced a section of underground lawn sprinkler black plastic pipe that runs over a septic drain field. Repair couplers do not leak until i press my foot down on one of four running sprinkler heads. Is that normal? [Would the leak have been due to the hair dryer i used to make the plastic pipe more pliable?](http://diy.stackexchange.com/questions/66559/is-it-ok-to-use-a-hair-dryer-on-underground-lawn-sprinkler-pipe) Hoping someone has tried the same stress test and would share their experience. Water pressure where I live is 85psi, but noticed most water garden hose accessories sold locally are rated to only 60psi. [1]: http://diy.stackexchange.com/questions/66559/is-it-ok-to-use-a-hair-dryer-on-underground-lawn-sprinkler-pipe