Question Exploded Power Supply Capacitor

[Sneak02]

My power supply exploded after trying to get my system on. Earlier i cleaned everything on my pc including the psu with a brush. After a good 3-4 hours i flicked my avr and theres no light on my motherboard so i switched it off, and unplugged it on the socket then unplugged the psu cable from the system and re-plugged it, plugged the avr on the socket and turned it on and after around 5-8 seconds theres a boom and smoke came out on the bottom so i assumed it was the psu, i unplugged everything from the socket and mobo then took the psu out and i found a blown capacitor, the motherboard lit up after it blew up and before i unplugged everything, psu socket also dont have a smell. What could possibly the cause? maybe shorted?
The capacitor had these tags on it (22oF50v )

 

[Lutfij]

Welcome to the forums, newcomer!

Make and model of your PSU and it's age? An image of the extent of the damage to the PSU would help two fold.