Called Cosmopolitan as my furnace was blowing cool air. This happened the previous two years and it was caused by a dirty flame sensor. I dealt with them last year and told them i'm sure it is the same issue. The man on the phone said the charge will be the same as the last service call on record. The Tech came, I told him that i'm sure it was the flame sensor, he checked the unit, cleaned the sensor, and charged twice as much as what i was quoted on the phone. I asked why was i being charged twice more then i was quoted, he said he was not sure about what i was quoted but that was the price for his service (he did not do anything more then the previous tech the year before). He applied a piece of tape on the furnace door safety switch (which you are not suppose to do, will speak to that in a moment) and told me if I continue to have issues I can check the flashing light in the unit and see the cause. Shortly after he left, the unit continued to blow cool air. So I called the tech, a day after he replaced the flame sensor and charged for the replacement. Shortly after he left, the unit still was not working. So I did some research myself, one thing i found was that the purpose of the furnace door safety switch is a safety device to prevent your furnace from pulling toxic gases into your home. When the panel to the furnace is removed, it cuts power. The tech tapped it so he could diagnose the problem, but he should have removed the tape when he left. So, I cut power to the unit, removed the tape, made sure everything was plugged in, restored power and the unit has been working fine since. I read online that taping the safety switch could cause problems, i cant say i understand fully, but i now have heat in my house. I now have doubts that the flame sensor needed to be replaced at all. I called the company, expressed my frustration and my belief that i was over billed, they said the best they can do is give me a credit on my next service call. I told them that there will not be another service all as i will not use their company again.