It's generally not recommended to place heavy furniture directly over floor vents for a few reasons:
Airflow restriction: Placing furniture over vents can obstruct airflow, reducing the efficiency of your heating or cooling system. It can disrupt the distribution of warm or cool air throughout the room, making it less comfortable.
Potential damage: Heat can damage certain types of furniture or objects placed directly over vents, especially if the vents are distributing warm air. This might cause warping or other issues over time.
Uneven heating/cooling: Blocking vents can create uneven temperature distribution in the room, leading to hot and cold spots.
If you must place furniture over a vent due to limited space, try to elevate the furniture slightly to allow some airflow. You can use vent deflectors or extenders to redirect the airflow away from obstructive furniture.
Regularly checking vents for blockages caused by furniture or other items and ensuring they are unobstructed will help maintain an efficient HVAC system and comfortable temperature levels in your home.