The Spanish right-back and his wife were given bags of unwanted sandwiches from a shop in the Welsh city and decided to try to find homeless people to donate them to.
However, the couple couldn't find a shelter on their own so took to the social network site.
"Anyone knows the location of homeless people in Swansea? I got food going spare! #randomtweet" he wrote.
Rangel has since explained in more detail his evening.
"My wife, Nikki, who is a very caring and charitable person, asked if we could have [the unwanted sandwiches] for the homeless rather than see them thrown in the bin.
"They agreed and we drove around Swansea for over an hour, but couldn't find any homeless people as it was so cold out on the streets with all the snow.
"We decided to tweet a plea and we were guided to a local charity shelter who looked after the homeless."
The 30-year-old, who will be in contention for a starting place against Stoke tomorrow, said that visiting the shelter on a regular basis was the 'least he could do'.
He added: "I don't know if we'll be as lucky with the free sandwiches in future, so I may have to cook some of my special Spanish omelettes instead."