Why would the air conditioner in my car work intermittently and not all the time?

I have a 2008 Honda Civic with about 190k miles on it (yes, it’s time to consider getting a new car). The air conditioner works intermittently. When it works, it’s great – nice and cold like it should be. But then it will stop working. The fan will stay on, the AC light on the dashboard will still be on, but the condenser will stop working.

I can’t predict when it will work. Sometimes it will take a few minutes to go on, sometimes a half hour. Sometimes it shut off after a few minutes and then goes back on, sometimes it will not shut off at all and then it will be fine the whole ride.

The outside temperature seems to have no bearing on the air conditioner’s functioning.

I have had a few times when I was driving at night or in the rain and it stopped working and then the windows got very foggy, which becomes a safety issue.

Do you know why this might be happening? I am willing to take it to be repaired, and I know that these things can cost some bucks, but I am just looking to not get ripped off, which is why it would be nice to try to get an idea of what the problem is.