Last winter I purchased a brand new Dyna-Glo Kerosene heater from
Walmart. It heats 1,000 square feet. It worked wonderfully well.

I used it approximately 2 to 4 times a week.
It stayed in the corner over the summer and was not used (although,
given how cool the sumer was, a few nights, I almost used it...hence
it being left inside and ready for use) I fired it up the other night
and it started with no problems.
I'm wondering if it needs to be cleaned in any way? How can I know if
the efficiency has dropped? the wick burns, just wondering if it
needs to be cleaned in some way?