The invention relates to a multi-condenser and double-return-air bypass dehumidification
fresh air unit and an
air conditioning method. The multi-condenser and double-return-air bypass dehumidification
fresh air unit comprises an air feed channel and an exhaust channel. A first
heat exchanger and an air feeder are sequentially arranged at the position of the air feed channel. A second
heat exchanger and an exhaust fan are sequentially arranged at the position of the exhaust channel. The second
heat exchanger is connected with an auxiliary heat exchanger. A first return air
bypass valve and a second return air
bypass valve are arranged between the air feed channel and the exhaust channel. According to the multi-condenser and double-return-air bypass dehumidification
fresh air unit, during refrigerating, the second heat exchanger serves as a condenser, a
refrigerant is condensed through the indoor low-temperature exhaust air, the
condensation temperature of the unit is reduced, and reheating is conducted through mixing of bypass return air and low-temperature fed air on the air feed side so that
cooling capacity losses caused by cold and heat offset can be avoided; in a heating inner circulation mode, an outdoor unit can be started to rapidly increase the indoor environment temperature; and in an outer circulation mode, the second heat exchanger serves as an
evaporator, the
refrigerant is made to be evaporated through the heat of indoor exhaust air, the
evaporation pressure and the heating capacity of the unit are increased, the
power consumption of the unit is reduced, and the frosting risk of the unit is avoided.