Edit- if you have a dedicated 120v circuit, you can very easily make it 240v. The reason it's 20amp is because that was the lowest amp 240 Breaker I saw at the store and I planned on putting 2 on it anyway. Unless it's in your wheelhouse, you might want to have an electrician make sure you have the space in your panel for the double breaker.
Not here I can't: Only single 120V to the property.
Fair enuf!
I still think itd be worth calling an electrician for a consult. 120v is a single breaker with a single hot and common. 240v is 2 hots on a double breaker. If you have a clothes dryer, it runs on 240v, like your HVAC as well. Its all done at your panel.