Air Cooling System for Home

[SimonWillis]

Hello everyone,

Is it more economical to operate the fan on my air-conditioning unit continuously or just turn on ceiling fans in the rooms in use?

Thank you

 

[Ralston18]

Window AC or central air?

I would expect that the AC would overall use more energy (KW) than the ceiling fans. Especially if the AC's BTU rating is too low for the room, rooms, and house.

Many factors involved.

Start with the following link:

http://www.consumerreports.org/cro/news/2014/06/how-to-size-up-your-air-conditioner-needs/index.htm

Overall, for my home, we use the ceiling fans first and then, if the room or rooms become too hot (and more likely too humid) we go to the AC's. A couple of rooms also have window ACs for the really brutal days and nights. Or visitors staying overnight in rooms normally not used that much. Two story house so the upper floor is often much hotter. Focus the cooling up there and let the cooler air flow downstairs. Vice versa in winter with respect to heating.

Trick is not to let the room get too hot/humid to where the AC has to run longer to get the room back to being comfortable. Or go even further and overcool the room.

See if you can figure out the power usage/requirements for the fan and AC. May be labels etc. on the AC especially for newer products. Maybe something on the ceiling fan or in its documentation. Check online as well.

A Kilowatt meter may help you monitor the AC's power use if you have window units.

Key is to keep the room temperature as steady as possible. It is the heating up and needing to again cool down that runs up the utility bill.

 

[mjslakeridge]

In the Spring, I start out with the ceiling fan and a small room fan in my upstairs office (400 Square feet). By mid-day, I turn on a portable room air conditioner (10,000 btu, not a window unit, but a free standing unit that vents the hot air to the outside via a flexible duct through the window). By late Spring/early Summer I will have to use the portable unit in conjunction with the central air conditioning unit upstairs (5 ton unit cooling almost 3,000 square feet). I keep the vents closed in the rooms not being used, and a good amount of cool air spills down the front staircase and over a balcony upstairs to cool 1/2 of my first floor which is isolated by doors from the other 1/2. For the 1/2 of my first floor that is used the most (kitchen, laundry room, breakfast room and master bedroom), I use the central air conditioning unit for that part of the house (2.5 ton unit) that is pretty efficient.

My biggest cost reduction came from switching from a high cost energy plan to one that offers a lower cost/kilowatt hour once I reach 1,000 KWH used per month. Living in southeast Texas near the Gulf Coast, in the summer I can easily reach 3,000 KWH used per month for 3-4 of the hottest months. During the hottest days, at night the temperature may only cool down to 80F at night and can reach over 100f in the afternoon (not for weeks on end, but mid 90f is common for about 3 months).