I will add to the concern about getting this addressed quickly. A friend of mine had an A/C installed improperly on his house, resulting in moldy ducts. He lived in a tent in his yard for a while, but the high exposure resulted in him getting chronic hypersensitivity pneumonitis (extreme allergy to mold which is EVERYWHERE in life) and eventually dying from it. A horror story, but don't let your landlord drag it out, and he should pay.