Leakage test in an air conditioner

Abstract

The invention relates to a method for servicing an air conditioner, particularly in a motor vehicle. According to the method, a test gas is applied at a defined pressure to the air conditioner cooling circuit that is depleted of coolant in order to perform a tightness test, and changes in the pressure are recorded and evaluated during a certain interval. The aim of the invention is to further develop such a method in such a way that the same can be carried out in a highly automated manner, rapidly, and without harming the environment. The aim is achieved by using a gas mixture of nitrogen and hydrogen as a test gas and inspecting the cooling circuit by means of a hydrogen probe once a drop in pressure has been recorded.

1 - 4 . (canceled) 
     
     
         5 . Air conditioner service device for servicing an air conditioner, particularly an automobile air conditioner, whereby the device can be connected, on the one hand, to a test-gas pressure bottle that contains a gas mixture composed of nitrogen and hydrogen, and, on the other hand, can be connected with the air conditioner by way of filling hoses, and whereby the device is set up to carry out the following method steps, for the purpose of the seal test:
 draining the refrigerant from the cooling circuit of the air conditioner,   applying the test gas to the emptied cooling circuit of the air conditioner, at a defined pressure,   recording and analyzing changes in the test gas pressure over a time interval,   generating a request for carrying out a leak localization by means of a hydrogen sensor if a rapid pressure drop is registered,   draining the test gas by way of a drain valve after completion of the seal test, and, if necessary, of the leak localization.   
     
     
         6 . Device according to claim  1 , wherein the test gas is a gas mixture composed of 95% nitrogen (N 2 ) and 5% hydrogen (H 2 ). 
     
     
         7 . Device according to claim  1 , wherein the device is furthermore set up for precipitation of entrained refrigerating machine oil from the drained test gas, and for returning the precipitated amount of refrigerating machine oil into the cooling circuit. 
     
     
         8 . Device according to claim  3 , wherein the precipitated amount of refrigerating machine oil is determined by means of weighing.