Drainage apparatus

A filter apparatus for an internal combustion engine, comprising:

• a water collection chamber;
• a water level sensor arranged in the water collection chamber for detecting a fluid in the water collection chamber;
• a drainage apparatus arranged downstream from the water collection chamber, the drainage apparatus including:
• a housing;
• a solenoid valve disposed in the housing and in fluid communication with the water collection chamber;
• a non-return valve arranged downstream of the solenoid valve, wherein the non-return valve is in the fluid communication with the solenoid valve via a chamber, and the non-return valve is fluidly connected on a downstream side with a drainage line to discharge fluid from the chamber and out of the housing;
• a pressure sensor arranged between the solenoid valve and the non-return valve, wherein the pressure sensor is configured to detect a pressure in the chamber disposed between the solenoid valve and the non-return valve;
• and
• a control apparatus operably connected to the solenoid valve and the water level sensor for draining the fluid from the water collection chamber to the drainage line in response to signals output from the water level sensor, wherein the control apparatus controls the solenoid valve to open and close in response to said signals output from the water level sensor, but does not control the non-return valve in response to said signals;
• a leak detection apparatus connected to the pressure sensor and the control apparatus, wherein the leak detection apparatus monitors the pressure in the chamber and a position of the solenoid valve to detect a leak in response to respective signals output from the pressure sensor and the control apparatus, but does not monitor a position of the non-return valve during operation of the leak detection apparatus.

A method for detecting a leak of a drainage apparatus, comprising:

• monitoring signals output from a water level sensor in a water collection chamber;
• controlling a solenoid valve to switch from a closed position to an at least partially opened position in response to said signals indicating a presence of fluid in the water collection chamber, wherein the solenoid valve is arranged upstream of a non-return valve, and wherein the solenoid valve is in fluid communication with the non-return valve via a chamber disposed between the solenoid valve and the non-return valve;
• communicating a signal indicating a position of the solenoid valve to a leak detection apparatus;
• monitoring signals of a pressure sensor for detecting a pressure in the chamber disposed between the solenoid valve and the non-return valve after controlling the solenoid valve to switch from the closed position to the at least partially opened position;
• and
• outputting a fault notification based on said signals of the pressure sensor unless said signals indicate a pressure increase and the solenoid valve is in the at least partially opened position;
• wherein the leak detection apparatus monitors the position of the solenoid valve and the pressure in the chamber for outputting the fault notification but does not monitor a position of the non-return valve during operation of the leak detection apparatus.