Low dew point air dehumidification assembly

Abstract

A dehumidifier apparatus ( 10 ) to provide low humidity air to an enclosure. The apparatus ( 10 ) includes an outer housing ( 11 ) providing six air passages ( 12 to 17 ). Also located in the outer housing ( 11 ) is a heat exchanger ( 22 ) that provides two air paths between which heat is exchanged. The apparatus ( 10 ) further includes coils ( 27, 28 and 29 ) as well as a motorised damper ( 18 ) and fan ( 19 ). The apparatus ( 10 ) further includes a refrigeration circuit ( 73 ) and controller ( 30 ), with the controller ( 30 ) operating the damper ( 18 ), fan ( 19 ) and circuit ( 73 ) to provide low dew point dehumidified air.

1 . A dehumidification apparatus including:
 a primary heat exchanger having a first air path and a second air path, with the heat exchanger providing for transfer of heat between air passing along the two paths;   a first air passage that directs input air entering the dehumidifier into the heat exchanger;   a second air flow passage that receives the input air after passing through the heat exchanger first path;   an airflow regulator, operatively associated with the first air passage and upstream of the heat exchanger, to selectively direct at least part of the input air from the first air passage to the second air flow passage so that air so directed bypasses the heat exchanger;   a first air cooling heat exchanger to which air is directed by the second air flow passage;   a second air cooling heat exchanger;   a third air flow passage that directs air leaving the first air cooling heat exchanger to the second air cooling heat exchanger;   a fourth air flow passage that directs air leaving the second air cooling heat exchanger to the second air flow path of the heat exchanger;   an air heating heat exchanger;   a fifth air flow passage that directs the air leaving the second air flow path of the heat exchanger to the air heating heat exchanger;   an air movement device that causes the air to pass through the dehumidifier from an air inlet to an air outlet, with the inlet delivering air to the first passage, and the outlet receiving air from the air heating heat exchanger; and   a controller operatively associated with the air flow regulator, air movement device, first air cooling heat exchanger, second air cooling heat exchanger, and air heating heat exchanger, so that air leaving the air outlet has a required absolute humidity and temperature.   
     
     
         2 . The apparatus of  claim 1 , wherein the air movement device is a fan or fans located in the fifth or sixth air passage but downstream of the heat exchanger second path, each fan being operable to move air through the passages and heat exchanger paths. 
     
     
         3 . The apparatus of  claim 1 , wherein the airflow regulator is a motorised damper. 
     
     
         4 . The apparatus of  claim 1 , wherein the controller operates the air flow regulator to govern the flow rate of air delivered to the heat exchanger first path, and the second air flow passage. 
     
     
         5 . The apparatus of  claim 1 , wherein the first air cooling heat exchanger receives chilled water. 
     
     
         6 . The apparatus of  claim 1 , wherein the second air cooling heat exchanger is an evaporator in a refrigeration circuit. 
     
     
         7 . The apparatus of  claim 1 , wherein, the first air cooling heat exchanger is a refrigerant evaporator. 
     
     
         8 . The apparatus of  claim 1 , wherein the air heating heat exchanger is a refrigerant condenser. 
     
     
         9 . The apparatus of  claim 1 , wherein the assembly includes a refrigerant circuit including an evaporator providing the second air cooling heat exchanger, and a condenser providing the air heating heat exchanger. 
     
     
         10 . The apparatus of  claim 9 , wherein the refrigeration circuit includes a further condenser, arranged in parallel with the air heating heat exchanger to discharge excess heat from the apparatus. 
     
     
         11 . The apparatus of  claim 1 , wherein moisture is inhibited from passing between the two air paths in the heat exchanger. 
     
     
         12 . The apparatus of  claim 1 , wherein the second air cooling heat exchanger is mounted horizontally to aid in draining condensed water or specially constructed for vertical installation. 
     
     
         13 . The apparatus of  claim 2 , wherein the controller operates the air flow regulator to govern the flow rate of air delivered to the heat exchanger first path, and the second air flow passage. 
     
     
         14 . The apparatus of  claim 13 , wherein the first air cooling heat exchanger receives chilled water. 
     
     
         15 . The apparatus of  claim 14 , wherein the second air cooling heat exchanger is an evaporator in a refrigeration circuit. 
     
     
         16 . The apparatus of  claim 15 , wherein, the first air cooling heat exchanger is a refrigerant evaporator. 
     
     
         17 . The apparatus of  claim 16 , wherein the air heating heat exchanger is a refrigerant condenser. 
     
     
         18 . The apparatus of  claim 17 , wherein the assembly includes a refrigerant circuit including an evaporator providing the second air cooling heat exchanger, and a condenser providing the air heating heat exchanger. 
     
     
         19 . The apparatus of  claim 18 , wherein the refrigeration circuit includes a further condenser, arranged in parallel with the air heating heat exchanger to discharge excess heat from the apparatus. 
     
     
         20 . The apparatus of  claim 19 , wherein moisture is inhibited from passing between the two air paths in the heat exchanger, and the second air cooling heat exchanger is mounted horizontally to aid in draining condensed water or specially constructed for vertical installation.