If a ball bursts or loses significant air due to temperature fluctuations, this is NOT covered by the warranty, is not a valid reason for complaint, and NO exchange or refund will be provided!
The ball should only be inflated to playing pressure during direct use. Otherwise, always release some air. It should not be exposed to direct sunlight (for example, at the beach or behind a window), as the ball may burst. The same result would occur if the ball is played with in cold temperatures and then stored in warmer rooms. The pumped-in air would expand, possibly damaging the bladder.