Answer: (1) Insufficient regeneration gas rate.
(2) Regeneration gas valve cannot discharge.
(3) During the regeneration cycle, the working tower pressure does not drop completely (cannot drop below 2kgf/cm²), resulting in a small pressure difference.
(4) The exhaust muffler is blocked.
(5) The exhaust valve cannot be opened.
(6) The check valve is stuck and cannot be closed normally.
(7) Improper setting.
(8) Timer failure.