Air-conditioning ventilation system and method for class-II dangerous area in closed space

The invention discloses an air-conditioning ventilation system and method for a class-II dangerous area in a closed space, and the system comprises an exhaust pipe which communicates the dangerous area with the outside and provides a channel for air exhaust; the exhaust fan is arranged on the exhaust pipe in the dangerous area and provides power for exhaust; the air conditioning device is arranged in the safe area and provides cold/hot air for the dangerous area; the air conditioning air supply pipe is communicated with the air conditioning device and the dangerous area and is used for supplying cold/hot air generated by the air conditioning device into the dangerous area; the airtight valve is arranged on the air conditioner air supply pipe and used for preventing air in the dangerous area from flowing back to the air conditioner device; and the automatic control box is arranged in the safety area and is used for controlling the air conditioning device and the airtight valve. The air conditioning device is c