12 Air Conditioner Tips to Beat the Heat

Leave a Comment - 119


John Carston

Subject: Air conditioning tips

This is helpful information to add to my list of methods I use for staying cool. I haven't had working air conditioning in quite some time but I've managed to keep a manageable temperature in my apartment. I'll use these weatherizing tips as I look for a suitable repair service to cool my home.


Subject: Ceiling Fans

It's great to run ceiling fans in the summer, but not to blow the cool air down. Cool air is heavier than warm air.


Subject: A/C Thermostat Temp. Adjustments?

Someone told me that we should not be adjusting our thermostat to our A/C by more than 3 degrees at a time, because this will burn up and wear out our compressor faster. Is this true?


Subject: Question about leaving fan "on" when unit it off

Hello, I have two Amana Heat Pump/Airconditioner units one upstairs and one down. The upstairs one is not working - needs a coil replacement and recharging. The AC tech told me to leave the fan "on" but the he shut the unit off and told me I could not run it until it was fixed. That unit sits in the attic. Last night it was 90 degrees upstairs (no lie) but it was much cooler outside. We have been sleeping in the living room. My question is... since the unit is located in the attic.. am I circulating the air in the attic (which is much hotter than ANYWHERE on the planet) into my upstairs by leaving the fan in ON position while the unit is off due to the broken coil? I think the tech was wrong to do that... thanks


Subject: Energy saving tips

1) Install a couple of blue ice "radiator packs: set at a 45 degree angle in front of a box fan mounted on the floor. This acts as an additional AC "Plenum". When the packs are no longer cool, simply refreeze them in your refrig freezer then repeat the cycle. 2) have a trusted energy contractor install an aluminum sheet like radiant barrier "shield" as a lay over in your attic. This will keep attic heat from radiating down to your home rooms. Do not install an attic vent fan. Though removing hot air out of your attic, this defeats the purpose when it can also draw in hot outside air. Also, know the formula: volts times amps = watts. Vent fans can use 7 or more amps of electricity. When multiplied by a 110 volt outlet, this equates to 800 watts or more. And it is the wattage that your electric company charges you for. Such vent fans are not economical.


Subject: attic fan

i have a attic fan that runs when my attic temp is 110 and shut off at 87 degrees.My attic only heats up to 122 degress.I dont mine spending money keeping my house cool .On most nights my fan shuts off by 1030 pm when your attic is still 100 plus.Then by 1 pm your attic is 150 and mine is 110. I hope this helps.


Subject: Additional Tip That Should Have Been Mentioned

A tip that wasn't mentioned but should have been is to close the shades on your windows directly exposed to the sun. For us this made a huge difference. We have 3 air conditioning units, one for the basement and one for each of the other two floors of our home (it's a huge home) with significant exposure to the sun on the second floor. When our second floor air conditioning unit went out we closed the blinds to all windows exposed to the sun during the day and that alone dropped the temperature by 4 to 5 degrees on the second floor. We now keep our shades closed while the windows are directly exposed to the sun.

Definitely worth considering if you're looking to save on your cooling costs.

Chris Jenkins

Subject: HVAC shade

A point in you're article is to keep the AC unit shaded. That's difficult to do artificially. Trees are great. But don't try to shade it by building something over it or having a new one installed under a deck. Most current AC units require at least 4' of clearance above them. The unit expels heat out of the top. That is heat removed from your home through the your refrigerant. Not enough clearance will make your unit work harder or fail prematurely. Check your units manual for proper minimum clearances.


Subject: More WINDOW air conditioner hints NEEDED , please...

Many of your readers have window units becausea) live in older housing stock, b) are apartment/condo/co-op dweller or c) have areas in their homes not frequently used or where using the CA is just plain silly(attached garage,anyone?)
I would love to see some attention paid to those of us who must wrestle with wildly high summer electric bills, lack of better filters than the cheap minimal filter usually supplied with the unit &, living on the 7th floor for example, can't water the building(!) or step outside to the clean outer coils. It is rare that the window units themselves last more than 2-3 years-/seasons. Any tips?


Subject: Split systems

Everyone is writing about central air (or window AC. But mini split systems like Mitsubishi can be more efficient and quiet than both. You don't have to cool the whole house, they're silent, low energy. I have two units outside with 4 heads cooling most of a 3 story house, though they almost never all run at once. It's zoned.


Subject: Mitsubishi Split AC

Ditto. I have a few Mitsubishi split AC units for my home and they work extremely well. They are very quiet and use much less electricity than central AC.


Subject: fan on all the time

What about leaving the AC unit fan "ON" rather than "AUTO"? The only disadvantage I can think of is....noise and the electricity it takes to run a fan. I wouldn't think it take too much to run a fan, and it may be offset by the savings of eliminating "hotter spots" in the house? Also, maybe the air would be slightly cleaner?


Subject: re: Fan On All The Time

When doing this in the cooling season a disadvantage is that the fan will evaporate the moisture left on the A-coil when the AC compressor turns off. This will put some of the moisture back into your home that you just spent precious $$ taking out of the air. I figured this out the hard way last summer (2015) when I set our system to run the fan continuously. I couldn't figure out why the indoor humidity wasn't as low as in previous years. Turning the fan switch on the t-stat back to auto dropped the humidity 5 to 10%. We live in mid-Michigan. Agreed that leaving the fan on will more evenly distribute the air and more effectively filter it. The new electronically controlled variable speed fans take very little energy to run.


Subject: Its good ideas about air

Its good ideas about air conditioning,thanks for all your comments,as though i came to learn about many things from your comments,thanks for sharing this blog,waiting for your coming threads.


Subject: Leave it on 80 or Turn it off?

I work in an office that is on the 2nd floor of a home. The owner turns the A/C to 85+ degrees at night. When I get to work in the morning, I turn it down to 75+ because it's so hot. I think (and I kind of remember being told this by an A/C person) that it takes more energy to cool it down from 85 to 75 than 80 to 75. It seems like it takes all day to cool the office. We have blinds on all the windows, use 2 large ceiling fans, and use desk lamps instead of overhead lights because they are just too hot.

I want to tell her, but I don't think she will believe me. Am I right or wrong? This is 97-98 degrees in Houston, TX.

Thanks...appreciate your opinions, especially if you are an A/C installer/repairman/manufacturer.

David Dean

Subject: Leave the AC near desired Temp for savings

If you turn the AC off at night when it is most efficient (no sun and cooler temps allow it transfer heat better) and let your rooms heat up and then try to cool the air, furniture, walls, etc. when the heat is building up outside you're forcing the system to run hard and never achieve comfort for anyone. If staff is uncomfortable, they will also be less efficient to some degree.
If it takes more that 30 minutes to achieve the comfortable setting, you have lost any potential savings. You may also be shortening the life of an expensive AC or Heat Pump unit.
We have found that raising the temp by 2 degrees at night works best. The unit can quickly recover the desired temp in the morning before the daytime heat hits. Everyone is happy and the unit will last. Let your boss know.


Subject: Cool at night. Off during day.

For optimal performance you should run the a/c at night to chill things off (maybe even a little chilly) and turn it off (or as high as you can tolerate) during the day. Leave your blinds down and still try to minimize heat input in the house and you'll be comfortable for most of the day. The load (energy) of an A/C is partly based on the temperature differential of the outside air vs. the inside air. The greater the temperature difference the harder a unit has to work. At night time the temperature difference is the least. You'll benefit from the a/c running most efficiently at night to dehumidify the air (a major factor that makes us feel hot and uncomfortable)as well as to cool the "mass" of the house, which because of different thermal properties "holds" cooler temperatures longer. And will keep the house cooler throughout the day.


Subject: leave it on

We had this issue at our church building. It's only used for any extended time a few days per week and we had been turning it off. We brainstormed with a super credible HVAC guy and he told us that turning it off was a mistake because when you turn it on the unit has to cool both the air and all the items in the rooms that had also been raised above the desired temperature. That makes the unit work harder than it ought to and also asks it to do something that may not be possible. Cooling off the items in the room is much harder than cooling the air.

If she is leaving it on at 85 already then your issue isn't as bad as ours where we turned it off completely, but it seems like a few degrees closer to your desired temperature will probably make a huge difference in getting the office to temperature but I don't know about energy savings.

Scentsy Katie Jones

Subject: Water on Central Air Condenser?

It has been above 90 degrees for the past month in Utah, where we don't have humidity. So I am wondering, will it help or hurt to spray water on the outside of our central air unit to help reduce cooling costs?

George Williamson

Subject: Water sprayed on a central air condenser

The outside unit of a central air conditioner is taking heat that has been pumped from the inside unit, and expelling that heat into the outside air. Cooling the coils on outside unit will cause heat to be expelled more efficiently. So it stands to reason that spraying water on the outside coils will help in cooling. This will not add humidity to the inside air. But CAUTION. Spraying water into an air conditioning unit that is running could be hazardous and may not be advisable.


Subject: water on central air condenser

one of the jobs of the air conditioner is to take the moisture out of the air to make us feel more comfortable. it sounds to me like it would increase the cost by making the part of the air conditioner that takes the moisture out of the air work harder using more energy to complete the task.


Subject: Math

The 8% math in this article is wrong. Not the figure, the math.


Subject: Depends On Where You Live

The percent savings per degree of setback is based on the typical indoor/outdoor temperature difference in summer. If you divide the temperature difference into 100%, you get the percent per degree. So the 8% figure would be based on a location with a typical indoor/outdoor temperature difference of about 12 degrees.


Subject: Article

I am not a professional but have had ac guys at the house all the time working through things for health issues and finally got it right. Anyway, as to the ceiling fan issue, if it is blowing the air on you (down) in the summer it does make you feel better b/c it helps evaporate the sweat and you feel cooler. But you will notice the air temperature goes up in the room . If you have the fan pull the air up then the air temp does go down a degree or so in the room b/c it is not pushing the hot air down. It is your preference. Also DO NOT leave the ac on auto with the fan on all the time or your humidity will rise quickly and even though your house may be cool, the humidity rises and you don't feel as comfortable. Believe me I have worked through that. The ac air that comes out of the vents can be slowed down which also helps with the humidity level. Also I did a test and left my ac on 75 all day and all night one month followed by leaving it at 80 when at work all day and then put on 75 when got home. This was during the summer months and found that there really is no significant savings on your bill. I am in Dallas, Texas. Learned a lot more as well b/c I have significant allergies and have to worry about humidity levels, etc. :-)


Subject: Ac unit

I'm hour south trying figure out good temp keep unit on

Bob McQuillan

Subject: A/C tune up

Be careful of companies offering discount prices for furnace ,boiler and air conditioning tune-ups . I have been in the business 33 years and people always ask me why I dont offer pre-season specials . It still cost the same to put a truck and a employee on the street summer or winter. Those companies that offer discounts have to find something wrong with your equipment in order to put that truck on the street. ie. they must sell you parts in order to cover overhead

Richard Lutes

Subject: Air conditioning

I have been in the air conditioning business for over 25 years and still have people ask me if I run free service calls like other companies do. There is no such thing as a free service call, they will find something wrong or tell you you need a whole new system in order to pay for that call. It is impossible to drive around all day checking air conditioning systems for free and still be able to eat. Pay the service fee and you are more likely to get an honest repair.


Subject: AC efficiency

We try to avoid running the AC when it's illuminated by the the sun during the heat of the day: That's when it's running least efficiently.

Another tip: If you find the bedroom gets too cold with an AC on in the wee hours of the morning, start cooling the room at a lowish setting about an hour before bedtime. Then, at bedtime, set the thermostat a couple of degrees higher. There is a lot more heat stored in the walls, floor and ceiling than in the room air. Once that solid stuff is cooled down, the full brunt of the cooled air chills YOU.



Our mobile home is 5 years old and in the summer months it becomes extremly hot. We clean the coils regularly. We have a 5 ton unit for a 2300 sqft home but some rooms tend to stay hot even in the evening although you can feel the air coming thru the vents. Our electric bill runs about 450-600 a month during the hot months hear in florida. Any suggestions as how to help with this issue and help us save money. Also it probably doesnt help that we only have 1 tree in the entire yard which doesnt give us much shade. We do have ceiling fans in all the rooms that somewhat help but the the house stays around 79 mid day when with the air condition is running and set to 75.


Subject: Solar Gains

We deal with a rise in temperature in summer months during specific times of day, depending where in the country you live. Example, in Chicago IL the highest solar gain is between 3pm and 5pm. What does this mean? It means the sun is at almost a direct angle into your building or home at this time. Most people think noon is high time for heating from the sun, which when it comes to our homes, the roof takes the beating for that time. During peak solar gain times, the sun is beaming its energy directly into the Windows, siding and ground. It causes the rise in temperature within our homes and structures. For those wondering why your AC unit is having a hard time keeping temperature in the late afternoon, this is exactly why. Use blinds or tint on those windows taking the direct hit. Also this is where insulation comes into play. If you live in a prefab home or mobile home, it's known the insulation inside the walls is not usually at maximum ratings. Only custom build homes or those people building structures with an architect or design engineer would have the foresight to increase insulation R-values in the high solar gain directions.
Solar gain however can help reduce Heating costs in winter time, due to the same principle.

D Zipper

Subject: A/C Tip No. 9

I have been hearing about clockwise vs. counterclockwise for many, many years. But, which is which?
No one has yet been able to tell me if the directions are determined while looking up from below or looking down from above the fan.
Anyone have an answer?????


Subject: Directions

If you look at the slant of the blade you can tell which direction the air will move and the direction of the spin is actually irrelevant. If the leading edge of the blade is higher as the fan spins, then it will blow air down. If you reverse the direction the fan spins, the the lower edge of the blade will be the leading edge and pull air up.
My fans happen to blow air downwards when spinning counter-clockwise when looking up at them. Its probably the industry standard but its not like there is a law requiring it.


Subject: three years ago- but for future reference

it's looking up at the fan. If you're looking up at the fan and it's going counter-clockwise, it's pushing air down. If you're looking up at the fan and it's going clockwise, it's pushing air up.

Nancy Cosier

Subject: A/C Tips

Here are some cheap, obvious ideas not mentioned--
Draw down the shades to the windows. This alone can keep rooms cooler. Consider investing in replacing windows/sliding doors with triple pane ones that are designed to work in your enviroment
Buy vent deflectors--can redirect air from flloor or ceiling vents to center of rooms.
Close off vents in rooms not used
Close doors to closets, pantries, unsed rooms unless it will effect airflow. I close off the laundry room so the heat from the dryer will not "spill" into the other rooms
Vaccuum the vents weekly


Subject: deflectors on return register

I have deflectors in the Summer on all of my supply vents, which were originally for just a forced air heating system. Does it make any sense to use deflectors on the returns? Or are deflectors only useful on the supply vents?


Subject: window tint

How does tint help keep your home warmer in the winter. It doesn't! All those energy tax credits on new windows are a joke for anywhere that gets below 40 in the winter. In these areas there are way more heating days than cooling days. Yeah I want to keep the sun out if I live in Duluth or Fargo, etc.



#9 ceiling fan:
I believe the only two times to run the ceiling fan are:
1. When you are actually IN the room.
2. When you have a short period of time to "harvest" the outside cold night air. The fan breeze will speed and deepen the cool-down of your walls, floor, and furniture.



Our July electric bill more than doubled after our shade trees all blew down.



about the ceiling fan it has to be going left to trow more air. if it goes right you can hardly fill it. i recommend left.



regarding item #12 on installing window film -- be aware that it may void the warranty on your windows.



G.A. Dadomo wrote:
contact coolnsave company, inexpensive easy to install money saver

This looks a bit like blog-spam, but perhaps deserves a comment:
Cool-N-Save makes a small system designed to spray mist on outdoor air conditioning coils. The evaporating water can, in fact, help the unit cool. The thing that *might* make this idea practical for a home-owner is that it can be installed without adding any electrical control valves. It uses a valve that is operated by air flow from the fan on the outdoor AC coil. Their web site markets the product with great enthusiasm.

It's not like there's nothing to it ... The misting theory works in practice *if* the valve is reliable, and *if* the misting nozzles perform as designed. A few cautionary words ...

I have no experience with this particular valve, so can't comment about its reliability. I have experience with commercial and industrial misting systems, though ... systems that cost thousands of dollars. The nozzles are cranky. They clog easily. They really don't like hard water. And they don't help as much when the weather is humid. Commercial misting systems used for cooling and humidification take a lot of maintenance time. Your money, and the worth of the maintenance time, might be better spent on a more efficient outdoor AC unit. An outdoor coil with a larger surface area gets the same efficiency job done, and will need a lot less maintenance. Maintenance that would need to be done anyway, even without the misting system.


Subject: Ac cooling

U wouldnt want to spray water directly on the coils causing hard water deposit build up which then u would need to have the coils cleaned causing more maintenance fees



It would be helpful to have two lists, one for central ail and one for only window units.



No. 10 is somewhat inaccurate. Concrete and cement-based products can help cool landscapes because it reflects the sunlight off of its light-colored surface whereas asphalt and dark-colored pavements absorb sunlight and cause the surroundings to become even hotter. This is similar to the urban heat island effect. Areas such as Hotlanta have successfully lowered their annual temperatures by adding trees and replacing asphalt with light-colored pavements.


Subject: Concrete & summer heat

This depends on region you live in. Our family resides in southwest states. Concrete, landscape rocks, sand, asphalt, boulders & cinder blocks all absorb heat May - October. 'Kool decking' around pools is a necessity, even with Flip flop type sandals. Small any color landscaping rocks, river rock, gravel & sand will fry plants in summer heat & hamper trees Death Valley warns that Summer ground temps get 13-20 degrees hotter than air temps. Hence the'hot August nights' festival, when hot breezes are 24/7. We found out that regularly wearing flat or low heel sandals in summer causes PAIN from dry & cracked bottoms of feet & toes. Even after 25 yrs, Healing requires swabbing with antibiotic type Ointment, wrap with gauze & cover with cotton socks during night time regularly. Mature palm trees offer cooler areas, as does the shady side of a cinder block wall, misting units, umbrellas & balconies. Because of small yards close together, our central AC/heat units frequently are engineered onto the rear roof of homes, unseen at frontal views. When installed properly, vibration, noise & leaks are minimal. 30% of our 20+ yr old subdivision still have original units. Northeast has 7-8 mos of winter, South has humidity year round, northeast has rainfall & southwest has ground heat. Fact of life.

G.A. Dadomo


contact coolnsave company, inexpensive easy to install money saver



If you want the science on ceiling fans, I recommend that you do a scientific experiment of your own. Try running the fan at its different speeds, and in each direction. (Some fans only run in one direction. Some fans reverse by reversing the pitch of the blades) Then sit or stand in the places in the room where you ordinarily expect to be. Use the set-up that gives *you* the most comfort improvement in *your* situation. Then walk over to your thermostat and turn the air conditioning temperature up a little bit ... and smile about the very real energy savings you just arranged for.

When you aren't in the room, turn the ceiling fan off. It only helps if it's blowing on you. If you aren't there to enjoy it , it's wasting its energy.



Don has it right about the fan motor energy. Cycling the fan uses less fan enrgy than running it full time. The starting load is high, but lasts only an instant. Also, the energy lost from re-evaporating moisture from the coil is an additional efficiency loss when using full-time fan. This is less of an issue in dry climates.

There are two effects that compete in importance when it comes to getting best comfort from whole-house AC. Intermittent fan gives better humidity control and uses less fan energy. However ... many installations fail to move enough return air from the upper level of a multi-story house. Typical recommendation is that *at least* 60% of the return air should come from upstairs. However, the ductwork is often not installed to do this properly. Some builders won't allow the heat/cool contractor to cut enough floor penetrations to get the job done. Or the new owner doesn't want to lose a square foot of precious closet space to accommodate an adequate return duct. Some older homes only have a common return on the first floor. In situations like these, it can be difficult to cool the upstairs adequately without running the fan full-time. If this is your situation, you may have to give up the energy savings and humidity control to have adequate upstairs comfort.



Everyone keeps referring to cleaning something in the attic with bleach? I don't have an attic so can anyone say where I should be cleaning?? My AC is running but not cool air, like room temp.



sheila, there is a switch on the fan herself. turn it off and you can switch it to the other direction.



To clarify the confusion on tip No. 9, the idea is that running a ceiling fan counterclockwise will create a downward flowing draft that makes the air feel cooler because it's blowing across your skin. This allows for some added comfort without having to lower the temperature on your thermostat.

Thank you for your comments.

Mark Mandel


We have window air conditioners, not central. Does this part of Pat Gallina's comment (7/20/2011) apply to window a/c?:
"Once you get the unit professionally cleaned keep the outside unit hosed down every few months to keep dirt build up"



How do i change the direction that my ceiling fan is turning?



Re ceiling fan direction: Imho, if your ceiling fan is close to an a/c vent, it should push the cool air downward in summer. If far away from a/c vent, pulling hot air up works better. Stand under the fan when it's pushing air down; does it feel cooler, or do you just feel movement? In our l/r the fan is very close to the a/c vent & makes a tremendous difference to have it pushing the cool air down more quickly.



I leave the ceiling fans off in the winter. They just create a draft that makes me cooler and less comfortable, not warmer. The normal starting and stopping of my single story system keeps the air mixed well enough.
Also, setting the fan to ON is not always the best thing to do. My air handling unit and ductwork is in the attic. Constantly moving the air through that unheated, uncooled space will just cost you dollars. In addition, my A/C unit is a high efficiency unit with a variable speed blower. It is designed to supercool the coils each time before the blower starts. This operation pulls a great deal more humidity out of the air than the type of system I grew up with. So its important to have the start/stop cycle functioning to reduce humidity.

Ric Secor


Make sure you maintain your equipment! This should take at least an hour, they should;
check airflow
static pressure
is the indoor coil and blower clean?
check superheat
May cost more $150.00



Running the AC's indoor fan intermittently leads to better humidity control, increasing system efficiency. Ideally, the fan should run for a minute or two after the compressor turns off. This scavenges the last of the cooling from the cold refrigerant remaining in the coil after the compressor shuts down. Modern electronic thermostats can often arrange for the indoor fan to act this way.

When the compressor runs, a lot of its energy is used to condense moisture on the cooling coil. This reduces the humidity indoors and increases the comfort. If the indoor fan runs full time, it re-evaporates the moisture that you just paid to condense on the coil. That moisture goes back into the living space, raising the humidity, and you get to pay to condense it again. For best comfort and system efficiency maximize the amount of moisture that drains from the cooling coil.



Ceiling fans are often misunderstood. Yes, the fan's motor adds a tiny bit of heat to the room it's in. But it creates much more comfort by increasing the evaporative cooling of the occupant's skin than it loses through that small amount of heat. You can be comfortable at a higher room temperature with a ceiling fan than without. So the air conditioning savings can greatly outweigh the fan's small energy contribution. Especially true if the air conditioner provides good humidity control

No matter which direction the ceiling fan runs, it tends to "de-stratify" the air in the room, making for more even temperatures. However, setting the fan so that the air blows down is generally better in the cooling season, and blowing up better in the heating season. In the cooling season, the downward flow's "wind chill effect" adds to the comfort. In the heating season it subtracts. These statements depend somewhat on where the people are arranged in the room.



Item #7 - regarding air conditioner sizing - not only will excessive cycling reduce the efficiency, it can contribute to humidity control issues. In my professional opinion, you are better off with an AC that is a bit undersized rather than oversized. It will only "fall behind" on the warmest days - but you'll be comfy anyway, because the indoor humidity will be lower. (This is an admittedly controversial opinion among professionals.)



Chuck, I believe you are wrong about the auto thermostat. If you are at work all day you should raise the temp a few degrees. Yes the system will run longer when you return, but will use less energy overall. The walls aren't going to warm up that much . its the air that fluctuates quickly. Also, don't downplay the effectiveness of the ceiling fan. It can make a room feel several degrees cooler.



i am totally confused about the use of ceiling fans and in which direction they should be spinning in the summer. would someone who really has the correct scientific answer tell me what to do. thanks



"A point not mentioned is the benefit of setting your A/C FAN switch to always "ON" rather than automatic. This keeps the air circulating throughout the house more uniformly; better balances the air temperature between basement, 1st and 2nd floors (when only a single unit or thermostat is controlling the cooling); and recognizes that the max electrical load on the fan is the starting load, so leaving the fan running 24/7 is equal or cheaper than having it stop and start with the A/C compressor. "

I think this is incorrect. I've put ammeters on fan motors and the starting current jumps only for about a second. A better idea is to run your fan for 60-90 seconds after the "demand for cooling" stops. I have a fancy thermostat (Honeywell TH8321u) which supports this. Even though the AC stops, the forced air fan runs for 90 seconds after. This not only circulates the air, but pulls some extra cooling off the coils.


Subject: Fan to ON is a bad idea.

Here in the south. Leaving your Tstats fan ON constantly will only increase humidity making the air seem sticky and not comfortable. Unless you have another source for dehumidifying the air when AC is not calling at T stat, leave stat on Auto to avoid high humdilty levels.

L Edwards


Having your unit serviced is a good idea. My service man found some worn out wires and a mouse nest in the electrical section.



If you have a hose, wetting down the outside of the building on the south/west side will take away a lot of heat, especially if your exterior is masonry. Ditto the concrete patio, stone landscaping close to the building. Do it as you water your plants each evening and the AC will go off much earlier because the walls will stop radiating to the interior.



Window film's good, but don't ignore outside hanging shades from stores like Home Depot. They cut some sun BDEFORE it hits the glass, will last a couple of years (if you take them down before southern hurricanes, round $26



As long as your unit has the power to bring the temperature down within a reasonable time, you WILL save by letting the unit off when you are away. That's basic high school physics.

Be sure to seal around window units. I use packing tape to cover the pleated panels on the side of the unit - these panels don't seal out the air. I cut a swim noodle in half and use a piece to seal the gap between the sashes.

When replacing a roof or siding, go with white or close to white to reduce heat absorption.

In humid weather, check your window units occasionally to see if they froze up. Condensation will freeze on the inside coils and stop the airflow. If this happens, turn the unit to fan only for a few minutes to melt the ice.



Great ideas about the air conditioning. As for ceiling fans, they run counter-clockwise in summer and concentrate the breeze straight down into the room where you can feel it's effects. In winter they should be run clockwise, then the warm air above them is pushed down along the walls.

Mike P


A word of warning about just "your A/C FAN switch to always "ON" rather than automatic." On some units this creates a pressure that prevent the condensate from draining properly and overflowing the pan. I'd turn it off for an hour or so a day to allow all to drain, maybe more in high humidity areas.


Subject: draining issues, fan on

We have installed systems with advance or ECM indoor blower motors. With these systems the fan never shut off, it will run 24 hours a day seven days a week. These fans run at lower speed when circulating air without a call for heat or cool. Running these fans cost roughly $50.00 - $70.00 a year. When in the on position you cant here the air moving, and in most cases you dont feel the air. Not only does this save money on cooling or heating cost, because the air is always moving and circulating between levels. This also keeps the air cleaner in the house, with the air exchanges constantly over the filtration system. Keep in mind you will need to clean, or replace your filters more often. Convential fan motors (PCS motors) can cost $400.00- $600.00 a year to operate constantly. The drain issue mentioned should never happen, if the system is properly installed with a drain trap, coil installed correctly, and the drain is primed before the cooling season. If the drain is primed, it eliminates the air lock which prevents the water from draining into the trap. If you have a furnace with air conditioning in the attic, you should always have a drain pan under the equipment with a safety switch installed in the pan. The safety switch should be wired into the low voltage circuit of the a/c system. The switch will active if water is present in the pan due to an overflow from the indoor coil or drain blockage. This can save costley sheet rock repairs. It is always best to have your equipment serviced each year by a certified contractor. The cost for this varies, but should take the technician at least 1 1/2 hours to do. We charge $159.00 for an a/c tune up. In all cases for tune ups you should have a journeyman technician performing this work for you. Many companies will hire and use a tranie to perform this work. This cuts there cost, and allows them to offer the service at a much lower rate. You get what you pay for.



OK, guys, if the ceiling fan thing is confusing you, just concentrate on the other 10 things to do. Let's not worry about the "gnat" and ignore the intent of the article.



I disagree with the comments that say #3 & 11 are the same. #3 is stating that shading your unit will assist it's effectiveness.
#11 Is in saying if you have shrubs near your unit. trim them to keep them a 2-4 ft distance from the unit so it can "breathe."

Mark Piscitelli


The ceiling fan will also generate heat all on it's own which contributes to the problem. Follow Chuck's advice and just turn on your furnace fan and leave it on, this is the BEST way to move air.
A thorough tune-up may cost upwards of $189 and can include a cleaning of the indoor coil. Dirty coils are the #1 problem with inefficient air conditioning. If you have a dirty coil (which way too many systems do) then none of these tips will make a significant difference, they amount to putting band-aids on a sinking boat.



Re #9 - It really doesn't matter which direction the fan is turning because the fan is circulating a fixed amount of air in the room. If it pushes it in the middle of the room, odds are the ENTIRE room's air is being mixed. The ceiling fan is for PERCEIVED cooler temperatures, not actual temperature change. All they do is move the air around, they don't cool it.

Michelle Jolly


Chuck is obviously an HVAC professional; like me.
I was all charged up; ready to say what he did... but he covered pretty much everything I would have.
The only thing I would add is a comment on the "shade" suggestion. Do Not build a shade over the top of your unit - or interfere with the air flow in any way... your unit needs to have 36" clear on the coils all around.
I might also add that many companies pay their employees based on a commission of what they sell.
Just a head’s up. Buyer Beware.

Michelle Jolly


Chuck is obviously an HVAC professional; like me.
I was all charged up; ready to say what he did... but he covered pretty much everything I would have.
The only thing I would add is a comment on the "shade" suggestion. Do Not build a shade over the top of your unit - or interfere with the air flow in any way... your unit needs to have 36" clear on the coils all around.
I might also add that many companies pay their employees based on a commission of what they sell.
Just a head’s up. Buyer Beware.

Linda Dyson


I wish I know which way to set the fan in number 9. I am more confused now after reading the comments


Subject: fan direction

It really doesn't matter which way you have your ceiling fan set. The point is, you are moving the air in the room, and that might make it so you can set the thermostat a touch warmer in the summer, and still feel comfortable. That will save you money. Experiment to see which way you like the fan set to turn. It is not as if one direction warms the air, and the other direction cools it. The fan is just stirring the air in the room.



well, so much for Angie's List's highly rated heating and cooling contractors.

Janee Jarrell


Pour a cup of bleach, followed by a good gallon of warm/hot water into the vent pipes in the attic when you turn the unit off for the season and then, before you turn it back on. It's worth crawling over whatever's in the attic to do it. If you need to call for service if it clogs and over-flows the drain pan, after emptying the drain pan, that's essentially all the service tech will do. The same goes for spraying out the bottom of the unit, if there is a space for leaves and debris to clog up. That too, was a $60 service all for the tech to use our hose. Also, if you have serious winter, consider getting a cover for the unit, it cuts down on the debris that can collect.

And an air conditioner should never need freon or coolant added unless there wasn't enough put in to start with. It's a closed system which means that an older unit does not use freon like your car uses oil. If it's not cooling because there's not enough freon, there is a leak. Period.



Re; #9 Since when does cold air rise ?



Don't forget about switching to CFL lighting instead of incandescent. Incandescent light is 90% heat while fluorescents not only burn cooler but also use 25% of the energy for the same amount of brightness, and last about 10X longer, win/win.


Subject: LED not CFL

If you talk to someone who really knows light bulbs they will tell you to buy newer LED's instead of CFL. Number one, if you buy CFL at all, make sure you have purchased ones which are MERCURY FREE. Many are not, and if you break a bulb you literally have a hazmat situation on your hands, as in don't vacuum, tear up and throw away rugs, throw away contaminated clothing and bedding. Seriously, read up on how to clean up a broken CFL if it contains mercury.
Second, the lifespan of CFL's seriously diminish if you turn them on and off alot. They are really a technology for commercial applications where the lights go on and stay on for 12-18 hours, or continuously. Also, if you have multiple recessed or other lamps on same switch/circuit, make sure you are using all the same bulbs, don't mix. Also reduces life.
LED's deal well with the on/off, the color of the light is better, and they never have mercury.



Re: number 9...Correct summer setting is forward, or counter-clockwise. Winter setting is reverse, or clockwise.



Kelly, No. 9 Is correct you always want your fan turning counter clock wise in the summer. This causes a downward breeze causing you to feel cooler, In the winter time you turn your fan to run clockwise which pulls cool air from the floor to the ceiling where warmer air is forcing the warmer air down.

Chuck Miller


• BEWARE of the "Annual Tune-ups" for discounted prices! These sales are often used by the vendor to "find" extras that are bogus and not included in the price -- charging inflated prices for material and labor for parts that are not needed; venting freon and then charging excess cost to replace; and charging exorbitant rates for house cleaning that the average home owner can easily accomplish.
• That's only ELEVEN -- Number 3 and number 11 are the same!
• Number 5 is not contextually correct, If you increase 8% for each degree colder than (BELOW) 78 degrees, that has no direct correlation with saving 8% for each degree (ABOVE) 78 degrees that you set your thermostat.
• Number 6 is INCORRECT. Setting back the thermostat for short durations (less than 24 hours or less) is easily demonstrated as NOT cost effective, and less comfortable. It takes a lot more energy to cool down a home over a short period, than it does to retain a steady state interior temperature. Allowing the home to increase inside temperature during shorter periods, allows building materials to heat soak which takes longer to return it to cooler states; to re-cool the house usually will occur during hotter periods of the day, rather than the cooler periods; and it allows humidity levels (moisture) to rise during the setback time, which causes the air to feel warmer and less comfortable and takes a much longer time to reduce again after the fact.
• Number 9 is factually incorrect. Heat rises, so static air closer to the ceiling is always several degrees warmer than near the floor. Using a ceiling fan PUSHES THE HOTTER AIR DOWNWARD, not the cool air! The main advantage to a ceiling fan is that it causes the air to be more uniformly mixed, floor to ceiling, AND it causes more rapid air circulation which allows perspiration to evaporate more quickly, thus cooling the skin and increasing comfort.
• A point not mentioned is the benefit of setting your A/C FAN switch to always "ON" rather than automatic. This keeps the air circulating throughout the house more uniformly; better balances the air temperature between basement, 1st and 2nd floors (when only a single unit or thermostat is controlling the cooling); and recognizes that the max electrical load on the fan is the starting load, so leaving the fan running 24/7 is equal or cheaper than having it stop and start with the A/C compressor.

Good Neighbor

Subject: Keep the Fan on A/C unit On instead of Auto

My A/C Specialist advises that you should leave the fan running all the time by turning the switch from "Auto" to "On". It takes more electricity to start and stop the fan than to run constantly. Second, it does keep the air circulated thought the house without having the cold and hot air pockets.



Re:number 9. Hot air rises, does it not? So you want to run the fan counter-clockwise in the winter, I believe.

Jim Wall


This advice is pure gold, as we have spent hundreds of $$$ and misery this year on our 17-year old unit for our home built in 1956...the cost soars quickly and miserably.

anne auguste


i would like to install window film to a few windows, Can you please tell me which type should I used.

Pat Gallina


Once you get the unit professionally cleaned
keep the outside unit hosed down every few months to keep dirt build up plus keep a check on your drainage line to make sure it does not back up in your attic. My husband suggests pouring some Clorox in the drain to eat mold build-up. He also has safety switches on our units so if there is a power surge, etc. it will not destroy the units. Our units are 20 years old and running strong.


Subject: 20 yrs running strong

Your system is 20 years old and running strong? That's great!! But how much is your out of warranty system costing you to run each month? Knowing you would save anywhere from 30 to 50% each month, having a new system will help you to breath a heathier environment. How can anyone choose to keep a system 20 yrs old? I would bet you will begin to have problems sooner than later and that your systems days are numbered. Btw. Are you checking capacitors and contractor points for wear? This is just a few more things needed to check your systems performance.



Great ideas. The dark film is one I am going to start with especially in my sunroom.

Most of your suggestions I already do except for the thermostat. We keep it at 75 degrees because we're comfortable with that temperture.

Nancy L Young

Subject: room temperature

It's not difficult to be comfortable with the termostat set at 65 or even 55 in the winter. If you're used to having it set at 75 and want to save money and contribute less to global warming, you can gradually reduce the setting a month at a time. If you feel cold, put on warmer clothes. If you've been sitting, stand up and do some vigorous exercise like jumping jacks, running up and down stairs or jumping rope. It's good for your body, your brain and the planet.



Window film voids your window warranty!!! Solar Screens are much better and the added benefits are to many to list.

B. Wulfe

Subject: ????????

Come on! IF something were to go wrong with the glass ( unlikely) it isn't that difficult to remove window film. A major differentiating factor between film and a solar screen is the view. If the window has a limited view or isn't something you care about; then screens are fine. If you want to have the clearest possible view (while reducing heat transmission) then film is a better choice. Also, most fixed windows will not provide a means of installing a screen; without screwing into the exterior frame (which would definitely void your warranty; with no option of reversing the install). You could mount on the side of your house, past the actual window frame; but this typically is not very aesthetic.

in the end, either solution is debatable; depending upon the specific installation. Neither should be automatically ruled out or in; without consideration of multiple factors (Cost, Savings to be gained depending upon regional environment, Aesthetics Desired, etc. ). Depending upon the age of your existing windows, it might even make more sense to replace them with modern Low-E or alternative insulating windows.



#9 makes no sense the way it is worded. Hot air rises and cool air sinks!



I have a friend in the AC business. His comment was if the AC is working well (15 degree or better differential) then leave it alose or you will waste your money


Subject: Friend in AC business

If your friend in the AC business has given you this advise. Your friend is probably old school. And if he is licensed, his license should be reconsidered offering this kind of advise. What is this AC friends of yours company name? He is giving you wrong advise. So don't listen to him. Let me ask you this, do you feel the same about your car? Don't service your car. What will happen if you take that advise? Your engine will eventually fail, leaving you stranded when you least expect it. My advice, don't listen to this friend of yours. NOT GOOD ADVICE.

Kurt Erickson


Another tip is consider installing radient heat barrier in the attic. I used Alenco (local KC company) to install their eShield product which is garanteed to save 25% in cooling and heating costs. I can really tell the difference in the 2nd floor this summer.

Bob Rinehuls

Subject: radiant heat barrier

Radiant heat barriers are something to possibly consider when building a home, but trying to retrofit one is probably cost prohibitive. Same result can be achieved by increasing attic floor insulation.

ty stover


I believe that #9 should read "Pull the cool air up" not down. Warm air rises and cool air sinks. Like a hot air balloon. That is why in the winter you run the fans the other direction to pull the warm air down.

Richard Dawson


Solar window screens are much more energy efficient than window film. Screens stop the solar heat gain BEFORE it hits the glass



#3 & #11 Are the same I'm sure you heard this befor


Subject: #3 & #11

Actually these are not the same. I re-read them and one is to keep the unit free of debris and the other is to have it shaded if possible.
Unless someone changed those tips before i read it, at least they are different now.

Mary Jo Dailey


re #9 Tpo... You want to pull the cool air up. Warm air rises, cool air sinks :-)



VJMOOSE, how's this - warm air rises and cool air sinks. Set the ceiling fan counter-clockwise in the summer to pull up the cool air and distribute it throughout the room. Set the fan clockwise in the winter to send the warm air downward and distribute it throughout the room.


Subject: Fan circulates the air no matter which direction

As it has been explained to me, and makes sense: either direction creates a convection which will push the warm air down and pull the cool air up, it's just a matter of whether that is happening directly under the fan or at the outer edges of the room. If the fan is sufficiently sized for the room and running at a sufficient speed, the temperature variation from the floor to the ceiling will be minimal. Having the fan blow the air down will provide a breeze, making it seem cooler (preferred in the summer). Having the fan pull the air up will prevent the breeze from hitting you (preferred in the winter). [Note: using the terms clockwise and counter-clockwise might not be the best way to describe how to set them, as our fans blow the air down when they are running counter-clockwise.]

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what should you pay.  You pay what you can afford.  1100sqft unit requires a min. of a two ton unit.  prices range from 2100-2900 depending upon the seers of the system.  13 seer is the min. the law requires  and for your situation with 1100 sqft.  do not worry about the seers as long as it is to code.  the bigger the house the more seers for economy.  1100 sqft is at the border line for a two ton system.  It is more important to have your new system balance, there is where you get the economy on your electric bill and gas.  Bryant, lenox, ruud and carrier are the brands you should stay with.All have the same basic factory warrantee and will last you longer than you expect as long as you maintain it with regular check ups twice a year once in the spring and then in the fall.

raymond gonzalez
koolray heating and air

APRStore.com offers a nice sizing chart for HVAC capacitors and furnace capacitors. Most of the capacitors I've looked at are $5 to $15 dollars, so a little less than Home Depot and Lowes.


Replacement is really easy, but be sure to watch a youtube video on how to replace it like this one: https://www.youtube.com/watch?v=_IpydZIsOJg


Stay safe and hire a professional if you feel unsure about doing it yourself!

The only thing of importance, is the hvac professional you choose to use. Alot of manufacturer's pieces are built relatively the same, and will last about the same amount of time. The thing that matters most is what you can not compare between companies, and that is the installation. Purchasing a system is not like purchasing a car, where no matter where you buy it, they are all the same. Each installation is different, and usually what you are paying for is the level of expertise, and quality of the installation, the company who will actual give you the warranty, and the comfort that you will receive. Manufacturers warranties disappear every day. They always have a loophole where they can get out of paying, but your local dealer wants to keep you happy for future work, and to protect his reputation in the communiy. Look up 4 year old Nordyne and Goodman warranty problems. Choose the HVAC professional first. It will cost you the least in the long run. I have had to totally redo plenty of installations that were just performed because of an uncomfortable customer, and a system that keeps breaking down. The equipment is only as good as it's installation, and over 70% are not installed correctly.
I think maybe you are confusing SEER, which is an efficiency-related rating (higher SEER means more effective use of the electric power used to compress the gas), and TONS rating, which is a measure of the total cooling power of the system. (Tons used to mean how many tons per hour of ice was used in evaporative cooling building systems - a Refrigeration or Cooling Ton equals 12,000 Btu/Hour of energy exchange. A BTU, which is another antique measure but still used, is the energy needed to change the temperature of a pound of water one degree fahrenheit. Unfortunately, because of varying humidity and evaporation, this is not readily related to house air heating or cooling without a lot of assumptions and some computations. Relating this to today's world - the Manuals BayAreaAc referred to account for all these energy conversions and determine an estimated cooling (or heating) requirement for your specific house. The type of construction, solar exposure, general climatic conditions such as average temperatures, humidity, and hottest and coldest normal ambient temperatures and desired inside temperture are all taken into account in the more sophisticated versions of the analysis, so there is no "standard", though a rough old rule of thumb was about 1 ton of cooling per 500SF of house. Obviously, this was a WAG only because it did not account for insulation, type of roofing, whether you live in Alaska or Miami, etc. The ACCA manuals do a very simplified form of evaluation to arrive at a "design", which generally will be adequate. OF course, highly precise calculations are not really needed because A/C units generally come in even ton ratings - so if you are at say 2.6 ton requirement you will be getting a 3-ton unit anyway. SEER ratings are not a direct measure of efficiency, but the relative difference between ratings gives you good idea of the unit's relative efficency in using electricity - so a 16 SEER should be about 19% more efficient (so roughly comparable lower electricity bill) than a comparably sized 13 SEER unit. 13 SEER is the lowest efficiency currently allowed to be built for general use, 19 SEER is about the highest efficiency made by pretty much all manufacturers, and about 25 SEER is the highest rated though very pricey shelf-item units, though special construction custom units can reach about 30 SEER. Note however, like any government sponsored rating, much of it is hooey when you get down to it - for instance, SEER ratings are figured based on 80 degree inside air temp and 82 degrees outside, when that is far from the normal case of mid to low seventies inside and high eighties or above outdoors. This makes the absolute SEER rating meaningless, but relative numbers still have meaning in comparing units. Note these efficiency ratings are for conventional air conditoners and heat pumps working in ambient air conditions. Ground sourced Geothermal or lake/river exchange cooling units, though initially more expensive in most cases, can greatly exceed the air-exchange unit efficiencies because they are exchanging heat with cold natural water rather than with a high-temperature outside air, and instead of continually compressing a gas are just circulating cold water. I worked on one geothermal cooling project which had almost infinite efficiency, which of course makes no sense - but the only power was for sensors and a control valve as the water flow was single-pass under gravity flow, so no power was used to circulate the water.