Ventilation device

Abstract

A ventilation device includes a temperature regulating coil that is capable of changing the cooling capacity at multiple stages, and that cools a supplied-air flow after having undergone total heat exchange by a total heat exchanger, a target indoor-humidity storage unit that stores therein a target indoor humidity that is a target value of the indoor-air humidity, and a control unit that decides the cooling capacity of the temperature regulating coil, such that the humidity of the supplied-air flow becomes the target indoor humidity, based on measurement values of an outside-air temperature sensor and an outside-air humidity sensor when the target indoor humidity is lower than an actual measurement value of the indoor-air humidity measured by an indoor humidity sensor.

1 . A ventilation device comprising:
 a casing that includes an air-supply passage and an exhaust passage;   an air-supply blower that is provided in the air-supply passage, and that blows outdoor air into the air-supply passage to form a supplied-air flow in a room;   an exhaust blower that is provided in the exhaust passage, and that blows indoor air into the exhaust passage to form an exhaust-air flow to be discharged outside a room;   a total heat exchanger that is located between the air-supply passage and the exhaust passage, and accommodated in the casing, and that performs total heat exchange between the supplied-air flow and the exhaust-air flow;   an outside-air temperature sensor that measures a temperature of the outdoor air;   an outside-air humidity sensor that measures a humidity of the outdoor air;   an indoor humidity sensor that measures a humidity of the indoor air;   a temperature regulating coil that is capable of changing a cooling capacity at multiple stages, and that dehumidifies the supplied-air flow after having undergone total heat exchange by the total heat exchanger;   a target indoor-humidity storage unit that stores therein a target indoor humidity that is a target value of a humidity of the indoor air; and   a control unit that decides a cooling capacity of the temperature regulating coil, such that a humidity of the supplied-air flow becomes the target indoor humidity, based on measurement values of the outside-air temperature sensor and the outside-air humidity sensor when the target indoor humidity is equal to or higher than an actual measurement value of a humidity of the indoor air measured by the indoor humidity sensor.   
     
     
         2 . The ventilation device according to  claim 1 , wherein the control unit stores therein reference data that defines the cooling capacity to each combination of a temperature and a humidity of the outside air, and determines a cooling capacity of the temperature regulating coil based the reference data and outside-air temperature and humidity sensor measurement results. 
     
     
         3 . The ventilation device according to  claim 1 , wherein when an actual measurement value of a humidity of the indoor air is higher than the target indoor humidity, the control unit sets a capacity value of the temperature regulating coil to 100%. 
     
     
         4 . The ventilation device according to  claim 1 , wherein when the indoor air is in an excessively-dehumidified state, the control unit causes the temperature regulating coil to stop cooling the supplied-air flow. 
     
     
         5 . The ventilation device according to  claim 1 , wherein
 the target indoor-humidity storage unit stores therein the target indoor humidity as an absolute humidity, and   the control unit calculates an absolute humidity of the outdoor air based on an actual measurement value of a temperature of the outdoor air measured by the outside-air temperature sensor, and based on an actual measurement value of a humidity of the outdoor air measured by the outside-air humidity sensor, and when the target indoor humidity is lower than the calculated absolute humidity, the control unit determines a heating capacity of the temperature regulating coil, such that a humidity of the supplied-air flow becomes the target indoor humidity, based on measurement values of the outside-air temperature sensor and the outside-air humidity sensor.   
     
     
         6 . The ventilation device according to  claim 1 , wherein when the ventilation device and air conditioners constitute an air conditioning system, the control unit changes the target indoor humidity based on number of the air conditioners in the air conditioning system, which are performing a cooling operation.