Will closing all but one vent in an apartment with central air cause leaks in the duct work?
Closing off some or most of the vents won’t cause any harm to the ductwork. The blower in your central A/C doesn’t develop much pressure. What it will do is reduce the total airflow through the unit, which causes the evaporator and condenser to run colder. Combined, there will be several effects: • The blower motor and compressor will use less power when they are running • The refrigeration cycle will be less efficient • The air coming out the vent(s) which are still open will be colder • Once warmed up to room temperature, the air will be dryer (less relative humidity) • You might get more noise (from higher air flow through the remaining open vents, and blocked off vents can make their own noise) • If the evaporator coil gets cold enough, it might freeze up, and you’ll have no airflow at all once it’s completely iced over. If this happens enough, you can damage the coil from the ice forcing joints apart. You’ll save some energy from the blower and compressor motors being less loaded,
