The cause of the different temperatures is actually very simple. Warm air goes up and cold air goes down. You can feel the difference in the air temperature moving up and down your stairs by crawling up the stairs. Cold air will hit you in the face as you crawl up the stairs.
Now that you know why it happens, what is the cure? Well, that is not as simple. Although it does not have to be expensive. It may even involve a simple flip of a switch. Fan switch that is.
We know that cold air is heavier than warm air. Cold air will work its way down until it finds the lowest level of the home or a room that it can not go any further. This leaves the warm air to move up and occupy the upper levels. In a 3 level split, the middle level gets the pressure from the bottom and the top. You could say it may even be a happy medium of comfort. The key to larger home comfort is to mix the air up and get a turn over effect. Here are some tips on how to make that happen.
- Leave Furnace Fan In “On” Mode. – This will move the air in your house creating a movement that will force cool air up and warm air down. Return air ducts in the lower level will suck in the cooler air and dispatch it to the warmer area of the house. The return air ducts will always be sucking warm air from the upper levels and mixing it with the cooler air in the lower levels.
- Use a Ceiling Fan – This will force the movement of air causing warm air to go down and cool air up. This is a way to move the air in an open floor plan and stairwell situation. This is a quiet and more energy-efficient way to move air. You can set the fan for quicker cooling or a nice steady flow movement.
- Close Off a Lower Room – A house may have a level that can be closed off by a door. This will hold up the cooler air from going further down. A return vent in that room will still allow cooler air to escape into the furnace return to circulate to the upper levels.
- Put a Box Fan in Stairwell - This is not the best option, but is an option. Be careful about bringing too much damp air from the basement into your living area.
The option of leaving your furnace fan on is the best option if you have a high-efficiency furnace with a variable speed fan. This would allow for a very low flow of continuous air that would not be heard but yet keep the flow of air going. The variable speed would be very efficient and save you money in comparison to an 80 percent furnace with a regular 2 stage fan.
Remember to check your supply vents to make sure they are open and supplying air from the furnace. It is common to open the vents in the lower levels and close the vents in the upper level during the heating season. Leaving your vents like with would cause the air-conditioned air to go to the lower levels. Opening the supply vents in the upper levels of the home and closing them in the bottom levels during the cooling season will push the cold air up to the heat where it is needed.
These tips are designed to help when your forced air system is sized correctly for your home. ContactMinneapolis Saint Paul Plumbing Heating Air to learn more about your system and to learn what we can do to help you experience the most comfort in your Twin Cities area home.