We have a reverse cycle airconditioner and when the technician was explaining the best way to use it he suggested using the FAN facility to keep cool in the evenings and advised that there really was no need to also install ceiling fans for air movement and cooling.
We had never thought to use our previous reverse cycle that way as we already had fans installed in our other house. Is anyone using the fan facility in their aircon to move air around to keep cool at night?
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I would not even consider to do that up here in FNQ.
The aircon would need to be on a high speed fan setting to even try to emulate the vastly better, and virtually silent, air distribution of a ceiling fan.
All three of our homes had ceiling fans in every room and we used them on most days of the year.
I would expect that the large circunference of a ceiling fan would push far more air, and with much less sound than an aircon running on fan only, and might be more economical.
And as the ceiling fan is pushing the air down in the middle of a room, it is likely to be better than an aircon blowing out air in just one direction or slowly sweeping across the room.
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Yes. Mainly when the temperature drops at night and the house is too hot to sleep. Open the windows and use the fan to spread the cooler air round the house.
You can also use it effectively in the winter if you have a fuel stove, the fan mode will spread the warm air around. Similarly if you have a sunny end of the house that gets the winter sun you can spread the heat to other rooms rather than open the windows of that room to cool it.
Fan mode is not as good as ceiling fans for evaporative cooling as the air current is not as strong or direct but it is good for redistributing heat.
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In NE Melbourne we have an evaporative system, 2 splits, and then ceiling fans in each room. Each provides a different level of comfort under different conditions.
Depending on the overnight temperatures and humidity when we go to bed we might run the evaporative system, the split, or mostly the ceiling fan. To your point, the ceiling fan moves more air gently throughout the room while the split will circulate it in a different manner with a different affect on comfort, blowing the air across the ceiling or right down on us, and the evaporative system is susceptible to temperature vs humidity so is only used when it will be efficacious.
YMMV in which combination or product you prefer but I would go with adding a ceiling fan.
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Itâs not that effective. The barrel fans in the splits will use more power than a ceiling fan and not be as effective in larger rooms.
When running our split systems for cooling we always run the ceiling fan/s on low at the same time. There are too many complaints that the air conditioner must be broken or needs to be set to freezing cold for comfort, otherwise. The same comment applies to the bedroom which is only 12m2, but does have 3.2m ceilings. The installed ceiling fan helps to circulate the air and promote more even cooling.
In our previous hot tropical North Queensland house - slab on ground with tiled flooring, thick block walls and insulated roof. Weâd often rely on just the ceiling fans for keeping cool. The fans were effective at circulating air from ceiling to floor where the cooler slab helped to keep the air temperature in the comfort zone. Depending on your bedroom or house construction YMMV.
I think it is more a perception thing than a science thing. Your Aircon expertâs not the one who will need to live with the consequences.
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I agree, unless one can feel the air being pushed by the fan.
Fans work by air moving over the skin, removing moisture (accelerated evaporation), causing a cooling effect. If one isnât subject to air being blown directly onto the skin, then the aircon fan will be as useful on as it would be off (possibly better off as it wonât be making any noise to disturb you including when sleeping).
Ceiling fans and mobile fans work best when the âbreezeâ created by these fans is directed to the mattress where one is sleeping.
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Lol. Well I got to test it out last night and you are correct about the noise. Like a small freight train in the background. Definitely think I will get fans.
Thanks.
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It had never occurred to me to use the fan that much anyway, so I was intrigued when he suggested it. You are correct it is not as effective in creating a breeze to cool the skin.
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I would not use the fan for my aircon as I have a fully ducted system and the ducts run through the roof space. In summer warm air is blasted out, and in winter cold air is blasted out until the cooled or heated air arrives.
I did try running the fan and checked the air coming out the vent at the furthest point. I monitored the temperature with an infra-red thermometer, which indicated when the air first came out, the temperature was much higher than the ambient and even after 15-minutes it remained well above the ambient. So, the air moving through the duct in the roof space was being heated as it travelled to the outlet!
So, using the aircon fan is quite useless and probably has a detrimental outcome!
(PS I live in Canberra).
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I live on the Gold Coast with fully ducted aircon and I use the fan setting a lot. I have a 2 x storey house and when I get home, upstairs is hot. I get nice breezes off the golf course, so I just open everything up and run the fan, I also put on the exhaust fans in the bathroom. I find it makes a huge difference and just gets the air moving. I sometimes just use it at night on timer for a couple of hoursâŠI quite like the background noise too!
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I am in Western Vic so summer temps often in 40C range. I have evap ducted system (original to house so now 13yo) and ceiling fans in every room of large house and did not even consider split system in recent reno. I put the money into improved insulation and ventilation in roof. Together with attention to room air circulation (doors and windows) that is more than enough for comfort.
It is NOT necessary to have your house at 20C in summer when itâs 35C* on the other side of the door. 28C with good ceiling fans and cross ventilation is very comfortable and I get that with minimal energy consumption. New ceiling fans are DC low energy and very quiet. They cost little to run and are much more comfortable to live with. They also offer benefits in winter if reversed to aid heat distribution and keep damp chill at bay. My ceiling fans are turned off only twice a year when I reset the direction with the change of season.
Needs will vary with nature of residence. If you are in a high density area with massive paved areas and reflected heat issues you may have no choice. But if you are in a free standing house consider improving roof insulation, tinting/insulating existing windows (way cheaper than replacing with double glazed), ceiling fans and air circulation.
If you have a particular area you use that gets very hot consider a floor fan. I recently invested in a fan that is part of a tool range so runs off standard rechargeable batteries for drills etc. The feeling of air moving at floor level can be very cooling and on batteries there are no cord issues to address. My fan runs for many many hours on one charge and has made a north facing corner room comfortable for me for comparatively low one off cost (buying fan that can be moved or packed away when not in use) and minimal running cost (recharge a battery).
Split systems offer fast and easy temperature modification but that does not make them the âbestâ. There are better ways to consider even if you already have a split system in your wall.
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Whatâs best - would seem to vary with where you live?
What might work best for existing housing designs for the tropical coast?
What does it take to build a comfortable tropical house free of air conditioning needs?
One that is typically nestled in a modern housing estate on a 350m2 âtraditionalâ mini block.
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We have ducted evaporative cooling here in Adelaide. For many years relied on that or on occasion just the fan function on many warm nights, often together with a pedestal fan.
Finally, we have recently also installed a ceiling fan over our bed. What a HUGE improvement to our comfort ⊠wish weâd done this years ago. Now, often the ceiling fan alone is satisfactory, and together (when needed) with the evap cooling or system fan, we feel confident about getting through even the hottest nights in reasonable comfort.
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It is not necessary, but personal comfort is an individual experience, and depending on the humidity evap systems can be all but worthless. In the early 2000s hot days locally had 15-20% relative humidity. Today it is commonly 30-35%.
This is the theoretical best case for air temp from an evap system, not including any impacts from heat buildup in the ceiling.
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Yes. Always use it when the day (and the house) begin to cool down, or just when we want a bit of gentle cooling. Why would you not? Depends on where you live I guess. Works well for us in Margaret River.
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Absolutely agree. Depends on where you are, type of housing, humidity, etc.
I deal mostly with dry heat. High humidity is entirely different but still benefits most from high air flow - fans and cross ventilation - which is not necessarily achieved by split systems.
We keep putting a peg in the ground about what environment we want to live in and using energy hungry technologies to bend our immediate surrounds to fit that perceived ideal. We need to bend at least a little to fit with nature. Fighting it is a battle we are never going to win.
Not looking to start an argument about benefits of rival systems. âBestâ is a personal perception based on individual circumstance. Just saying I was surprised how easy it was to achieve a very comfortable environment without hi tech system. Alternatives can and should be considered, esp when renovating or building from scratch. I have had friends used to their air con homes comment how cool my house is in summer and I point to thermometer read of 27-28C. They walk in from much higher external temp and feel air movement. It is probably 10deg cooler than outside, but not the 20-22C they have their home systems set for.
BTW - currently 34C outside and rising fast with blustery north wind. I have appropriate windows and doors open and ceiling fans only running and it is 21C inside. Brick house 15yo surrounded by paving, no trees and black tile roof (came with the house unfortunately!) after a very mild night where temp did not dip below 20C and four pretty hot days. Might or might not turn evap system on for an hour late this afternoon when sun hits big north facing windows. But not bad for an older house with minimal ongoing energy cost.
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We have a ducted full home airconditioning system. When we had it installed we had a fresh air feature also installed, which means that when we select that option half the recycled air is replaced with fresh air from outside. Please note I am not talking about the tiny little fresh air vent that some installers use, ours is a full size intake on the roof and supplies 50% of the return air when used. So what we do is everytime the outside temperature is cool enough, which is most nights, we just choose the Fresh button and this stops the heat pump, shuts off half of the return air vent and opens the outside intake. This means we get filtered air and little cost. It is a brilliant system and I canât understand why other air conditioning installers are not doing it.
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Thatâs what we set our split systems to in summer where we now live in coastal Qld. Comfort here is not about temperature. Itâs all about lowering the relative humidity to achieve comfort.
Outside today itâs overcast, itâs 28C and 64% RH. The BOM says it feels like 31C. Is there an environmental cost to running a split system on such a day? Not if itâs properly maintained and run from our rooftop solar. And not the sort of conditions in which evaporative coolers will be effective.
Some good news is the more tropical parts donât have miserable wet and cold winters like the southern half of Australia. When occasionally it does get cold and wet here in winter, a reverse cycle split air conditioner is also a great way to warm the room, without using gas or large amounts of electricity - grid or rooftop PV.
Itâs not about whether evaporative or refrigerant air conditioners are better. They deliver different outcomes because of the way they work.
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We have reverse cycle aircon and 2 years ago installed ceiling fan to improve air circulation. It is most efficient and reduces considerably the time the aircon is switched on, in both winter and summer.
JC Adelaide.
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