My chimney for heating in winter has to go out through the window on the door. Some people say that it destroys Feng Shui, right?

You burn briquettes, right? This is normal, otherwise, if it is not ventilated, it will be the same as turning on the gas in the kitchen of commercial housing or not opening the window in the gas water heater in the bathroom, and it will be unconscious and suffocated because of carbon monoxide poisoning. Only with the improvement of living standards and the deepening of urbanization can you change this situation in your family. It has nothing to do with feng shui.