A gas injection hose comprising: a hose having a coupler at a distal end thereof, wherein the coupler is adapted to be detachably coupled to a gas inlet/outlet valve of a thermal exchange apparatus; a movable depressor disposed in the coupler, wherein the depressor is configured to depress a valve core , wherein the valve core is disposed in the valve 7 to open or close the valve, wherein the depressor extends from the coupler into the hose in a length direction of the hose ; a depressor-adjustment unit disposed on a middle region of the hose , wherein the unit is configured to allow forward or reward movement of the depressor toward or away from the valve core , wherein when the coupler is coupled to the valve , a depressed extent of the depressor is adjustable by the depressor-adjustment unit , the gas injection hose being characterized in that : the hose is divided into first and second sub-hoses with the depressor-adjustment unit being interposed between the first and second sub-hoses, wherein the depressor-adjustment unit includes first and second hollow plungers coupled to the first and second sub-hoses respectively; and a rotatable hollow cylinder constructed to receive the first and second plungers, wherein the plungers are slidably received in the cylinder , wherein an adjustment plate is received in the cylinder and is integral with the cylinder, wherein the plate has a rectangular hole through which the depressor passes, wherein the depressor is received in a guide tube , wherein the depressor is partially thread-coupled to the tube , wherein a rotation of the cylinder allows a rotation of the depressor to allow forward or reward movement of the depressor toward or away from the valve core along the tube . a hose having a coupler at a distal end thereof, wherein the coupler is adapted to be detachably coupled to a gas inlet/outlet valve of a thermal exchange apparatus; a movable depressor disposed in the coupler, wherein the depressor is configured to depress a valve core , wherein the valve core is disposed in the valve 7 to open or close the valve, wherein the depressor extends from the coupler into the hose in a length direction of the hose ; a depressor-adjustment unit disposed on a middle region of the hose , wherein the unit is configured to allow forward or reward movement of the depressor toward or away from the valve core , wherein when the coupler is coupled to the valve , a depressed extent of the depressor is adjustable by the depressor-adjustment unit , the gas injection hose being characterized in that : the hose is divided into first and second sub-hoses with the depressor-adjustment unit being interposed between the first and second sub-hoses, wherein the depressor-adjustment unit includes first and second hollow plungers coupled to the first and second sub-hoses respectively; and a rotatable hollow cylinder constructed to receive the first and second plungers, wherein the plungers are slidably received in the cylinder , wherein an adjustment plate is received in the cylinder and is integral with the cylinder, wherein the plate has a rectangular hole through which the depressor passes, wherein the depressor is received in a guide tube , wherein the depressor is partially thread-coupled to the tube , wherein a rotation of the cylinder allows a rotation of the depressor to allow forward or reward movement of the depressor toward or away from the valve core along the tube . <EOS>