A:AnswerMark, not sure about the charcoal filter but it does come with a stainless screen which is on the underneath of the microwave that you would clean every so often. Yes this can be used without duct work to the outside, that's how I am using it.
A:AnswerOk. Just read user guide & yours may be in energy saving mode or standby mode. Look online or in user guide to reset so lights & stuff stays on.
A:AnswerOnce a month just fill your sink with hot soapy water and let the filter sit in it for a while and rinse off. It will last forever if you do that.
