If your home suffers from uneven cooling, you’re not alone. Many people find that the air temperature in their home differs from floor to floor, and even room to room — sometimes significantly. Various factors in your home, including system age, ductwork problems and even dirty filters can reduce a system's ability to cool your home evenly. Multi-level homes are particularly prone to uneven cooling issues. Because heat rises, it is difficult to cool a two story or multi-level home with a conventional central air conditioning system. An upstairs room in the house feels hot even though a room downstairs stays cool and comfortable.
Following are considerations if you are experiencing uneven cooling in your home.
#1 Dirty filters
Filters become dirty over time as they remove contaminants from the air. Once dirty, they need to be replaced or they can create a blockage that prevents the air conditioner from moving enough air through the system to keep your indoor spaces cool.
How often should air filters be changed? There is no hard and fast rule. It will depend upon how often your system is running, if it is subjected to dusty conditions, or if you have fur-bearing pets in the house. It will also depend upon the type of filter you have.
#2 Blocked vents
Room vents distribute cold air from supply ducts. When vents are blocked, rooms do not receive the cool air intended for that area. Vents can be inadvertently blocked by carpeting, furniture, and other items, or louvered vents could be left in the closed position. When air hits a blocked vent, it will redirect to other areas of your home with open vents.
You can redirect air to certain areas by partially (but not fully) closing some vents in the cooler areas. This way, more cool air will redirect to the warmer areas. By only partially closing the vents you can reduce the pressure build up in the system that would be caused if you were to fully close them. It is important not to fully close or block vents. Doing so results in pressure buildup in your ductwork that can lead to equipment strain and damage.
#3 Clogged ductwork
Over time, air ducts can become clogged with dirt, dust, debris, and other matter. The worse the buildup becomes inside the ducts, the harder your air conditioner has to work to push cool air through. If air ducts get blocked by built-up debris, a common side effect is hotter rooms in some areas of your house.
If you suspect this might be your problem, consider having your air duct system cleaned. With this service, all of that built-up debris is removed, along with particulate matter and allergens that can cause respiratory irritation. You’ll have fresher and cleaner indoor air and a home that cools more evenly from room to room.
#4 Ductwork leakage
When there’s an air leak present within your duct system, the air meant for a specific destination bleeds off before it can arrive there. These leaks in your ducts will definitely make your central air system work harder to compensate for the missing air. That, in turn, can lead to even more problems. You might have a professional inspect your ducts if you suspect that leaks are contributing to uneven cooling in your home.
#5 Fan setting
Thermostats have a fan switch that you can set for either “on”, or “auto”. Some modern thermostats have even more fan control settings. You might try turning the switch to the "on" position rather than the "auto" setting. When in "auto", the fan runs only when there is a call for cooling and the outdoor unit is on. In the "on" position, your system’s fan stays on and circulates air, even after the cooling cycle goes off. This serves to continually circulate the air in your home to help even out temperatures.
Depending on the type of furnace blower you have, running the fan continuously will add a little to your electricity use.
Your attic’s insulation serves the dual purpose of keeping your cool air in and the hot outside air out. If you lack the proper amount or quality of insulation, you may not be getting the full benefit and comfort of your valuable cool air. Make sure you have the proper amount of insulation in your attic. Also, make sure that the insulation has the proper R-Value for your type of home and region. Add insulating material where needed.
#7 Short cycling
Short cycling refers to when the air conditioner compressor starts and stops before a full cooling cycle is complete. You can listen to your central air conditioning system to determine if this is occurring. Generally, the compressor should run for more than 10 minutes at a time. A compressor running for less time won’t allow cool air to reach every room.
Some of the possible reasons for short cycling are; a dirty air filter causing the system to overheat, frozen evaporator coils, a poor thermostat location or malfunction, wiring and electrical problems or an incorrectly sized air conditioning system. Solving short cycling should be done right away. This issue can damage your system and lead to higher utility bills.
#8 Add a zoning system
While a zoning system is a large investment, it can be one of the most effective ways to deal with uneven cooling. These systems allow you to directly control the temperature in individual areas or floors. The number of zones recommended will depend on your current heating and cooling situation and the type, size and layout of your home.
One type of zoning system you might consider uses dampers in your ductwork as well as individual thermostats in each zone to control cool air distribution. When you set the thermostat temperature in one zone, the thermostat communicates with your AC unit, the fan, and dampers installed within the home’s ductwork to direct cool, conditioned air to that space alone. With zoning, it’s easier to send cooled air only where you need it.
Another type of zoned HVAC system involves ductless mini-split units. Instead of using dampers, multiple indoor air handlers are installed throughout your home, each with its own thermostat. You can install up to 9 indoor mini-split units for each outdoor condenser.
#9 Air conditioner age
During its years of use, your air conditioner loses efficiency and the ability to cool your home. A room that is located farthest from the unit will stay warmer while a room closer to the air conditioner can be cooled down. If your air conditioner is between 15 and 20 years old it may be time to consider its replacement. Today’s newer equipment is much more efficient and should not only cool your home better but result in a lower utility bill.
We would be happy to evaluate and make suggestions to reduce the uneven cooling in your home. Just give us a call to schedule our visit.