O.K. guys and gals, here, I believe, is a new one...

Due to suggestions that the problem might be the charcoal filter, I have tried to remove it but have been unable to turn it. I've lifted the bar on top to unlock it but it will not budge. Probably because it's not been removed for the past ten years. I'm thinking about getting an oil filter wrench to see if I can put enough pressure on it to break it free. Any thoughts?