Heat exchange unit

Abstract

A heat exchange unit performs at least one of a cooling and a heating of a liquid medium that is sent to a utilization side equipment. The heat exchanging unit includes: a heat exchanger that exchanges heat between a flammable refrigerant and the liquid medium; a casing that accommodates the heat exchanger; a drain pan with a bottom plate and a side wall that extends upward from the bottom plate; and a first gas detection sensor that detects presence or absence of a gas of the refrigerant in an internal space of the drain pan. The internal space is a space within the drain pan that is surrounded by the bottom plate, the side wall, and a virtual plane passing through an upper end part of the side wall. The drain pan is disposed below the heat exchanger in a lower part of the casing.

1 .- 8 . (canceled) 
     
     
         9 . A heat exchange unit that performs at least one of a cooling and a heating of a liquid medium that is sent to a utilization side equipment, the heat exchange unit comprising:
 a heat exchanger that exchanges heat between a flammable refrigerant and the liquid medium;   a casing that accommodates the heat exchanger;   a drain pan with a bottom plate and a side wall that extends upward from the bottom plate, wherein the drain pan is disposed below the heat exchanger in a lower part of the casing; and   a first gas detection sensor that detects presence or absence of a gas of the refrigerant in an internal space of the drain pan, wherein the internal space is a space within the drain pan that is surrounded by the bottom plate, the side wall, and a virtual plane passing through an upper end part of the side wall.   
     
     
         10 . The heat exchange unit according to  claim 9 , wherein
 the first gas detection sensor has a first detection element disposed in the internal space of the drain pan, and   the first gas detection sensor detects the presence or the absence of the gas of the refrigerant at a place where the first detection element is disposed.   
     
     
         11 . The heat exchange unit according to  claim 10 , wherein
 the bottom plate of the drain pan has an inclined part that is inclined with respect to a horizontal plane, and   the first detection element is arranged on a lower end side of the inclined part.   
     
     
         12 . The heat exchange unit according to  claim 10 , wherein
 at least one of the bottom plate and the side wall of the drain pan includes a drain port that discharges water from the internal space of the drain pan, and   the first detection element is disposed adjacent to the drain port.   
     
     
         13 . The heat exchange unit according to  claim 10 , further comprising
 a float disposed in the internal space of the drain pan, wherein   the first detection element is attached to an upper surface or a side surface of the float.   
     
     
         14 . The heat exchange unit according to  claim 10 , further comprising
 a second gas detection sensor with a second detection element disposed outside the casing, wherein   the second gas detection sensor detects the presence or the absence of the gas of the refrigerant at a place where the second detection element is disposed.   
     
     
         15 . The heat exchange unit according to  claim 10 , wherein
 an opening is formed in the casing, and   the first detection element is disposed in a space adjacent to the opening.   
     
     
         16 . The heat exchange unit according to  claim 10 , further comprising
 a pump that is disposed inside the casing and that sends the liquid medium to the utilization-side equipment, wherein   in plan view, an inside of the casing is sectioned into at least:
 a pump arrangement area where the pump is disposed; and 
 a refrigerant side area where a refrigerant pipe through which the refrigerant flows or the heat exchanger is disposed, and 
   the first detection element is disposed closer to the refrigerant side area than the pump arrangement area in plan view.