electrical calculation please

Amazon wrote:
REMOVES 18 OUNCES PER DAY: Optimal function in room sizes up to 2200 cubic feet (220 sq ft)

That's 1.125 pints/day. It doesn't sound like much. Before you put it in, buy a humidity indicator and let it sit in the room a couple of days. Then bring in the humidifier and let it run a couple of days (make sure to empty the catch pan so it won't shut off) and see if the reading on the indicator changes any. 55% humidity is enough to get a musty smell. You won't know if it works till you try it but don't expect much.

I bought a 20 pint/day Frigidaire dehumidifier from Lowes a few years back. I never thought it was working very well (I ran a hose to the floor drain in my basement so I didn't know exactly how much it was doing). The second season I could tell it wasn't doing anything. It had lost it refrigerant charge - everything was running but nothing was happening. I took it back, they gave me another one just as good and let me keep the first one. The second one didn't do any better than the first one. I sat them aside and bought one Harbor Freight was selling - $100 delivered. It worked great but after many years, I saw a recall notice (fire hazard) that covered it and they sent me another one that I'm still using today. I scraped the old ones out and got about $45 all total for the 3 compressors. The name brand units at Lowes weren't worth bringing them home. If you buy one be sure to get an extended warranty to cover it more than what the mfg does. They don't repair them so if it acts up (as they often do), you end up with nothing to show for your money. I've got the tools and experience to repair them but they're not made to work on.