Uneven cooling in a house is frustrating. You might be tempted to keep adjusting the thermostat every time you move from one room to another. Below are some of the possible causes of uneven cooling.
Supply vents deliver cool air to different parts of the room. Anything that blocks the flow of cool air will reduce cooling in the affected area. For example, carelessly placed furniture blocking a bedroom vent will reduce the flow of air into the bedroom. In such a case, other parts of the house will be cooler than the bedroom.
The ductwork is a series of channels that direct air to and from different parts of the house. Again, your house won't cool if something is interfering with the flow of air through the vent. Here are some vent problems that can do that:
Foreign items in the vents block the flow of air. Debris or dead animals are common causes of duct blockages.
Cracks or holes on the vents leak cool air or allow warm air to get into the vents. If that happens, the affected rooms might receive decreased air or warm air, both of which lead to impaired cooling.
The size, diameter or width, of the vent determines the volume of air it supplies. If something, say a fallen tree, crashes the vent, then it will have a reduced volume. The affected rooms will suffer decreased cooling.
Proper house insulation separates the exterior and interior temperatures. That way, the outside temperature doesn't affect your interior temperature. Inadequate insulation, especially in the attic, can allow the outside temperature to affect the air inside the ducts.
The effect will be there even if the technician designed the proper ductwork, and the ductwork hasn't suffered any damage. The affected ductwork will deliver warm air, and the affected rooms will be warmer than other rooms.
Different Cooling Needs
Lastly, your house can also suffer from uneven cooling due to different cooling needs. For example, in a multistory building, the upper level will be warmer than the lower level. The discrepancy arises because warm air is lighter than cool air — hence warm air tends to rise. Thus, if you subject the two levels to the same cooling output, the upper level will remain slightly warmer than the lower level.
Uneven cooling has multiple causes. The best way to deal with it is to get a professional diagnosis from a technician specializing in air conditioning service options.