Looking for a quiet portable air conditioner can be a big chore when it comes time to find an air conditioner that won’t annoy you every time you turn it on. Trust me, I’ve recently been through this task so I understand the frustration. As far as I’m concerned, if you’re going to spend the money on a portable air conditioner make sure it’s one that’s quiet.
Yes, it will cost a little more money to get a quiet portable air conditioner but it’s not much more and in the long run you’ll be better off, not to mention that you’ll sleep better at night.
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Best Quiet Portable Air Conditioner
Now that we’re in the middle of summer, keeping our homes and workplaces cool is at its most important. A portable air conditioner is a fantastic way to keep a room cool if you don’t have a central AC unit. In some buildings, central air conditioning cannot cope with certain rooms that get hotter than the rest of the building, a portable AC is the best way to add that additional cooling power to make it comfortable in an area that could, otherwise, be unbearable.
We rely heavily on our air conditioners in summer, but an energy efficient AC with a heat pump is just as good at keeping us warm in winter, so getting a good unit is worth the investment.
In areas where humidity is a factor affecting our comfort, an air conditioner is the best way to control this. Cooling the air will reduce humidity by the mere fact that cooler air cannot hold the same amount of water vapor as warm air. Most AC units have additional features that allow for increased dehumidifying and in hot coastal areas, this can be a huge advantage.
Having an air conditioner in the same room as where you are working or relaxing can be a major distraction. Noise levels can be excessive with some AC units. An air conditioner in the bedroom can keep you awake at night and a quiet machine will make the world of difference. So we’ve looked for quiet air conditioners that can be placed anywhere without causing a disturbance. Modern engineering has made it possible for an AC unit to generate noise levels that are low enough to be below the sound of a normal conversation.
Having selected a good variety of quiet air conditioners, we’ve set about to review these models in an effort to help you make the right choice. This article intends to help you find the best quiet air conditioner that will service your needs, match your budget and won’t look out of place in your living room, bedroom or office.
When choosing a quiet air conditioner, you’re bombarded with so many facts and figures. So it’s understandable if you’re left scratching head and asking a lot of questions. What is CFM? What does BTU mean? What is EER? What is the best dB for a quiet air conditioner?
After reviewing what we consider to be the best quiet air conditioners, we’ll answer all these questions and more. We’ll help you to fully understand the terminology used when looking at air conditioner specifications. To make things clear, we’ll inform you as to how an air conditioner works, this will help you better understand what to look for in a quiet portable air conditioner.
But first, let’s take a look what your options are and then we’ll move on to informing you on the ins and outs of choosing a quiet air conditioner that works for you.
Whynter ARC-122DS Elite — 52 dB
Although this is a dual-hose air conditioner it can also be operated with a single hose. Dual-hose is far more efficient but at least you have the flexibility to choose with this model.
Features:
- 12,000 BTU Cooling
- ECO-FRIENDLY CFC free GREEN R-410A refrigerant
- Lead free RoHS compliant components
- Patented auto drain function fully exhausts all condensate automatically in most environments
- Three operational modes: Cool, Dehumidify, and Fan
- Digital and remote control
- LCDI (Leakage-Current Detection and Interruption) plug
- Dehumidifying Capacity: 76 Pts / day
- Upper and lower drain ports for continuous operation
- Designed to provide quiet and efficient cooling to any room, with no permanent installation
- 3 speed fan with 2-way directional air louvers
- Equipped with Carbon air filter and washable pre-filter
- Full thermostatic control (61°F – 89°F)
- Casters for easy mobility
- 24 hour programmable timer
- Noise level (dBA): <52
- Auto restart after power outage
- Extendable exhaust hose (up to 60″)
- Upgraded Plastic window kit included
- Window kit length: Max. 46″
- Air Flow (at high speed): 264m3/h / 155CFM
- Maximum cooling power consumption: 1000W / 9.0A
Overview | Whynter ARC-122DS Elite
In my opinion, a portable air conditioner has to be good looking. It’s an appliance that has to blend in with your décor, especially if it’s going to be placed in your living room or office reception area. The Whynter ARC-122DS scores average points in the looks department, it’s very neat and compact and has a clean look in an attractive silver color. Though, I think the shape is a little box-like. Maybe that’s just me.
Moving beyond looks, we really want to know how the unit performs. After all, you’re spending your money on something that needs to get the job done efficiently. As far as noise levels go, the Whynter is excellent. At 52 dB, you can place it anywhere and you’ll hardly notice that it’s there. The compressor is virtually inaudible and you really only hear the sound of the air that is being moved by the quiet running fan. It’s a noise that is by no means unpleasant, pretty much like the sound of a refreshing breeze, which what it is.
A dual hose system makes it very efficient, by taking in fresh air and expelling the hot air. The window kit provided for the hoses has a maximum length of 46” and the maximum hose length is 60”. This means that you can place it at a good length away from the window that you use for the intake and exhaust hoses. You can choose to use it with only one hose if this suits you better.
While the Whynter ARC-122DS Elite has a very square design with a functional look, it’s very compact and this compensates for the rather unimaginative shape of the machine. It has a width of 17”, the depth is 16” and it stands 29.5” tall. These dimensions give it a very inconspicuous presence, even in the most elegant of rooms.
A 3-speed fan with directional louvers that move in two directions, give you good control over the airspeed and flow. This allows you obtain the maximum cooling effect without the discomfort of being blasted by a gust of cold air. With the fan set at a low speed, you’ll hardly the machine at all. The fan has an air movement capacity of 155 CFM. This is powerful enough to circulate the cool air in an area of up to 400 square feet. It is highly effective for cooling the area with a 12000 BTU cooling capacity.
It’s very efficient and eco-friendly, making use of Green R-410A refrigerant, which is free of CFCs. With the compressor running, it uses 900W of power (maximum power rating is 1000W), giving it an excellent energy efficiency ratio (EER) of 12. Later in the article, we’ll look at how to view the EER of an AC unit.
A programmable 24-hour timer helps increase your energy savings. You can program the unit to switch on at a time that ensures that the room is comfortably cool before you enter and then switch off when you’re not there, only using power when needed. It has a very accurate thermostat that can be set from 61°F – 89°F. A remote control adds to convenience of owning an air conditioner by putting all of the functionality at your fingertips. Let’s be honest, we all expect our gadgets to have a remote control nowadays.
Both your health and comfort are well taken care of, the Whynter ARC-122DS has a carbon filter, a washable pre-filter and a dehumidifier that is capable of removing 76 pts/day. It has three modes of operation: Cooling, fan and dehumidifying. Components are lead-free and RoHS certified. It’s also fitted with an LCDI (Leakage-Current Detection and Interruption) plug, this adds to your safety when using it. As an extra convenience, the Whynter will automatically restart after a power interruption, like when the power trips or there’s a power failure.
It has both upper and lower drain ports and the Patented auto drain function exhausts 100% of all condensates in most environments. You don’t need to worry about water collecting around the unit. Weighing 60 LBS, it’s not a very heavy piece of equipment, though you shouldn’t need to lift too often as it has castor wheels which make it easy to move about.
In a nutshell, the Whynter ARC-122DS is a compact and very quiet room air conditioner with excellent features. Designed and built to exceptionally high quality standards, it comes with a 1-year warranty for the complete unit and a 3-year warranty on the compressor.
Learn more about the Whynter brand.
De’Longhi PAC N130HPE — 51 dB
- 13,000 BTU/hr cooling power – For rooms up to 500 sq feet
- 4 in 1 operation – Cooling, Dehumidifier, Fan and 3810W Heat pump for all season use
- Removes from 54 to 86 pints/day of excess humidity
- Easily portable due to its durable castor wheels, tool free installation in minutes
- Easy-to-use with digital controls with LCD display, Timer function and fully featured remote control
- Dehumidifies While Conditioning: Removes 54,95 pints/24h of excess moisture.
- Dehumidifying Only Function: Removes 86,65 pints/24h of excess moisture.
- 3 Fan Speeds: Including QUIET mode to ensure the maximum quietness.
- No Drip Technology: Exclusive condensate re-circulation system with No Drip Technology. More efficient and more user friendly – never empty a bucket again.
- Easy Access Washable Air Filter.
- 12h Digital Timer and Thermostat.
- “Fan Only” Function.
- Handles and Castors.
Overview | De’Longhi PAC N130HPE
I’m particularly fond of De’Longhi products, so this one really appeals to me. All their designs have a certain flair that adds a touch of grace to an otherwise purely functional item. The De’Longhi PAC N130HPE is without a doubt a good looking appliance. It’s graced with curved lines and a tapered look that gives it a very minimal appearance. Not that it’s a large machine, measuring 17” X 16” X 29.5”. It’s exactly the same size as the Whynter ARC-122DS but its design gives it a less bulky feel. It’s just as easy to move around with handles and castors.
As for performance, the De’Longhi is a real winner. Delivering a 13000 BTU cooling capacity and airflow of 250 CFM at low fan speed and 206 CFM at maximum fan speed, the fan is adjustable with three speeds, including a quiet mode. This means that it is powerful enough to provide sufficient cooling for a room measuring 500 square feet. When used as a heat pump, the De’Longhi PAC N130HPE is able to produce 3810 watts of heating energy.
This comes from a very efficient and quiet running compressor that uses R-410A (CFC-free) gas. Even though the De’longhi has better performance figures than the Whynter alternative, it’s a little quieter. Though the difference between this model’s 51dB and the other one’s 52dB won’t really be noticeable. They are both incredibly quiet. It fairs better at dehumidifying too at 86.65 pts/day with the dehumidifier setting and 54.95 pts/day when in air conditioner mode. Like its counterpart, it can operate as an AC, fan only or dehumidifier, with the added benefit of heating in winter.
It has easy to use controls and also has a remote control. The De’Longhi PAC N130HPE has great programming functions which include a 24-hour timer, sleep mode, and a smart mode – though I’m not exactly sure what this smart mode does. From what I can figure, the De’Longhi smart mode is a self-diagnostic setting that checks for problems with the unit. By making use of no drip technology which recycles the condensate, there is no moisture collection. The washable air filter is very convenient and easy to access. It makes use of a single hose that has a window attachment.
So I would say that in this size range, the D’Longhi Pinguino PAC N130HPE is a real winner. It’s wonderful to look at in classic black and packed with feature. When it comes to performance, this air conditioner offers amazing cooling power and a good heating capacity at an incredibly low operating noise level. A truly magnificent product.
Learn more by visiting the De’Longhi site.
Whynter ARC-142BX — 53 dB
Recommended for spaces up to a 500 sq. ft.
Features:
- 14,000 BTU cooling capacity
- 2 in 1 silver-ion coated washable pre-filter and activated carbon filter
- Adjustable digital thermostat control range from 62° – 88°F
- Casters for easy mobility
- 24 hour programmable timer
- Noise level : up to 53 dB
- Auto restart after power outage
- Extendable exhaust hose (up to 59″)
- Upgraded Plastic window kit included
- Window kit length: Max. 48″
- Refrigerant: R-410A
- Air Flow (at high speed): 540 m3/h / 317 CFM
- Maximum power consumption: 1480W / 12A
- Power supply: 115 V / 60Hz
- Unit dimensions: 19.25″ W x 15.75″ D x 32″ H
- Net weight: 76 lbs
✓ View or download the MANUAL for the Whynter ARC-142BX .
Overview | Whynter ARC-142BX
The Whynter ARC-1428BX is similar in its function the smaller ARC-122DS. It has a completely different look and the overall impression is much more stylish and modern. It looks great in black. While larger, it remains portable and neatly compact, measuring 19.25” (Width) X 20” (Depth) X 32” (Height). Strong casters make it easy to move around when needed.
This portable air conditioner has a greater cooling capacity of 14000BTU, making it suitable to provide excellent cooling for an area of up to 500 square feet. The increased capacity of the Whynter ARC-142BX means that it has a higher power consumption (1480W Max power) and is slightly louder when running at full power, though this will be hardly noticeable at 53dB. The weight also increases marginally to 76 LBS – not exceptionally heavy for an AC of this size.
It has a four-speed fan with directional louvers to ensure excellent air flow which, at maximum fan speed, reaches 317 CFM. It has programming functions that include a 24-hour timer and can operate in four different modes – auto, air conditioner, fan or dehumidifier. When set to the dehumidifying function, it will extract 71 pts/day of moisture from the air. A digitally controlled thermostat can be adjusted between 62°F and 88°F, giving you very accurate control of your environment. All this is made easier with a full function remote control.
Window kits extends up to 48-inches. Check your window size.
The exhaust hose can be extended up to 59”, which gives one a good deal of mobility if don’t have a window close to the position where you are using it. The window kit can be adjusted for windows up to 48” in length. The self-evaporative system will control the moisture build-up that results from condensation and under normal conditions, you shouldn’t find any water collecting around the machine. It also has a direct drain option for continuous operation without any moisture build-up.
In line with modern ecological practices, it uses GREEN R-410A refrigerant, containing no CFCs. The air in the room is kept perfectly clean by a 2 in 1 washable silver-ion pre-filter and an activated carbon filter. Other health and safety features include an LCDI plug and RoHS compliant lead-free components. It’s designed to help keep you healthy while lowering its environmental impact.
The Whynter ARC-142BX is a good option for a quality AC for a large area. I don’t see a warranty agreement for this model on their website but I would assume it’s the same as the other Whynter model that we looked at the beginning of this review – 1-year general warranty and 3 years for the compressor.
Honeywell HL14CHESWW — 52 dB
4-in-1 function: cooling, heating, fan and dehumidification
Features:
- 4-in-1 Function: Cooling, Heating Fan and dehumidification.
- Cooling Capacity: 14.000BTU
- Heating Capacity: 11,000BTU
- Cools areas up to 550 sq.ft*
- Built-in Dehumidifier removes up to 111.6 pints/24 hours*
- Easy Access Washable Air Filter Helps catch unwanted dust particles from the air.
- Auto-Evaporation System: No bucket to drain.
- 3 speeds with 24 hour energy-saving programmable timer.
- Easy installation kit included, no professional help needed.
- Brackets are interchangeable.
- Environmentally friendly R410A refrigerant.
- Powerful air flow (241 CFM) and quiet operation (52 dbA)
- Adjustable Temperature 60F to 90F (16C to 32C)
- Digital Control Panel & Remote Control.
- Window bracket can be installed vertically or horizontally — adjustable from 26.6″ to 49.6″
- Weight: 74 LBS
- 5 Year Limited Warranty
✓ View or download the MANUAL for the Honeywell HL14CHESWW.
Overview | Honeywell HL14CHESWW
This very elegantly designed, white portable air conditioner compares well to the other larger AC units that we’ve looked at with a 14000 BTU cooling capacity. It’s able to provide cooling for a large area, rated at up to 550 square feet.
If controlling humidity is important to you, the Honeywell HL14CHESWW will make a big impression, it has a really great dehumidifying capacity of 111.6 pts/day. It is also able to heat the area with an 11000 BTU heating capacity.
Like the others, it has excellent programmability which includes a 24-hour timer and remote control. Providing you with ease of use and maximum power savings. The three-speed fan is capable of 241 CFM, which is not quite as powerful as the others, but still pretty good. Noise levels are within the same range at 52dB. The thermostat is adjustable from 60°F – 90°F, it’s accurate and reliable. There are four modes of operation that you can choose – fan only; cooling; heating or dehumidifying.
The window kit is more versatile than most and can be adjusted either vertically or horizontally between 29.6” and 49.6”. It’s easy to install and also has an auto-evaporating system that eliminates the need for water draining as a result of condensation. There’s also an option for continuous draining when operating for long periods under excessively humid conditions. As one would expect from a modern unit, it uses eco-friendly R-410A refrigerant. With a similar weight of 74 LBS and excellently designed castors, it’s as easy to move about as any of the others.
So the beautifully designed Honeywell HL14CHESWW can stand proudly among the others. While it may have a less powerful fan, none of the others can compare with its ability to remove moisture from the air. It also has a very impressive 5-year warranty.
Whynter ARC-12S — 52.5 dB
Features:
- Cools up to a 400 sq. ft. space (ambient temperature and humidity may influence optimum performance)
- 12,000 BTU cooling capacity
- Three operational modes: air conditioner, fan or dehumidifier
- Casters for easy mobility
- 3 fan speeds
- Full thermostatic control (61°F – 89°F) with digital readout, 24 hour programmable timer
- Remote control, upgraded plastic window kit (46″ max.), carbon air filter and washable pre-filter included
- Dehumidifying capacity of 91 pints per day, 3 fan speeds. Includes extendable exhaust hose (up to 60″) and window kit (up to 46″)
- Max. window kit length = 46″ , Min. window kit length = 20″
- Full thermostatic control 61 °F – 89 °F
- Digital display allows precise temperature control
- 24 hour programmable timer
- Remote control lets you easily adjust the temperature and function mode
- Activated carbon air filter removes odor and smoke and a washable pre-filter
- Auto restart after power outage
- 91 Pints/day dehumidifying capacity
- Patented auto drain function fully exhausts all condensate automatically in most environments
- Upgraded plastic window kit (46 in.) and extendable exhaust hose (up to 60 in.)
Overview | Whynter ARC-12S
For many, the very modern, sleek design and platinum finish of the Whynter ARC-12S will be a big plus. If you’re into modern design and the looks of your air conditioner is important, you’ll be attracted to this one.
Despite being quite a bit cheaper than the Whynter ARC-122DS, it outperforms the more expensive model in some aspects. The Whynter ARC-12S is capable of the same cooling capacity (12000 BTU) but is better when it comes to dehumidifying, capable of 91pts/day. It’s suitable for the same size area, being around 400 square feet and the noise levels are basically the same – 52.5dB.
Video | Whynter ARC-12S
It has a 3-speed fan, circulating at up to 188 CFM and can operate as a fan only, air conditioner or dehumidifier. The Whynter ARC-12S has programming functions similar to that of the others with a 24-hour timer and it also has a remote control. A digital thermostat allows you to accurately control the temperature between 61°F – 89°F.
Where this model isn’t as impressive as the other 12000/btu Whynter option is that it doesn’t have the dual pipe system, making it less efficient. So while this one is cheaper to buy, it will be slightly more expensive to run. Other than this, it fairs very well when compared to the more expensive Whynter model. It has the same dual filter system, an active carbon air filter, and a washable pre-filter. It also has the safety LCDI plug and certified lead-free components and uses CFC-free R-410A refrigerant.
The window kit is the same, extendable up to 46” and the exhaust hose can be extended up to 60”. It weighs only 62 LBS and measures 17” X 15.5” X 35” with castors for easy mobility. Water condensation isn’t a problem because this air conditioner also uses an auto evaporation system that uses the excess water to cool the condenser.
Being a very compact and elegant piece of equipment makes the Whynter ARC-12S a very attractive option. For its price, it offers excellent performance and makes use of great technology. The Whynter ARC-12S comes with a 1-year warranty and a 3-year warranty on the compressor.
Interpreting the Specs
To help you get a grip on the terminology used for air conditioner specs, we’re going to unpack this and explain what it all means.
As we’re concentrating on quiet air conditioners, let’s start with noise levels. Decibels (dB) is a unit of measurement used for sound levels. Without a point of reference, it’s not easy to determine what dB is a good level for a quiet air conditioner. If we put this into context, it’s a good idea to look at the noise level of a regular conversation. An average speaking voice is approximately 65 dB. So if we look at the quiet air conditioners in this review, you’ll see that they’re all close to 50dB, making them barely audible – not much more than a whisper.
The next spec that would be of importance would be cooling capacity and this is measured in Basic Temperature Units (BTU). This measures the heat transfer capabilities of and air conditioner. In order to understand this, we should take a quick look at how an air conditioner works.
The concept of heat transfer is applied to both heating and cooling. When heating an area, heat is transferred into the environment and when cooling, the heat is transferred out of the environment. To do this an air conditioner uses the principle of changing an element from liquid to gas or the reverse, depending on whether it’s heating or cooling.
If you think of a pot of water on a stove, as heat is added (transferred) to the water, it begins to boil. Boiling water releases steam, this means by adding heat to water it changes its form from liquid to gas. If the heat is removed from the steam, by a heat transfer back into the surrounding environment, it converts back into a liquid (condensation). Essentially this is a transfer of energy in the form of heat.
Any fluid will remain as a liquid at higher temperatures when pressurized. We can see this in practice when using a pressure cooker. When water is heated under pressure, it won’t turn to steam at the normal boiling point. This principle is true of all elements. The gas used in air conditioners is in a gaseous form at normal atmospheric pressure. When it is pressurized by using an electric compressor, it turns into a liquid.
When you depressurize it, by releasing it from the compressor, it will revert to gas. During this process, heat is transferred. When changing from liquid to gas, heat from the surrounding atmosphere is needed as a catalyst for the reaction. When converted from a gas to a liquid, heat is transferred into the surrounding environment.
A copper heat transfer is used to control the exchange of heat. When the gas is decompressed the refrigerant passes through a radiator and heat from the surrounding air passing through the radiator is transferred into the refrigerant as part of the reaction. This means that air that moves through the radiator is cooled, heat is drawn out of the air and taken up by the liquid in the radiator.
The rate at which the heat is transferred is measured in BTU. You can view a BTU as a bundle of heat. So if a room has 1000 BTU, we can say it has 1000 bundles of heat. When you enter the room, your body is constantly releasing heat, adding extra bundles of heat into the room. Sunlight does the same and so do the machines that we use. So there’s a constant release of temperature bundles or BTUs into the air. In order to keep the temperature at a comfortable level, the extra BTUs have to be removed to cool the room or added to heat the room. Depending on the size of the room, a certain amount of BTUs are needed to achieve this.
When the ambient temperature is high or the room is full of people or there’s a lot of computers all emitting heat, you’ll need a greater BTU capacity to cool the room. So if we say that an AC with a capacity of 12000 BTU is capable of cooling a room of up to 400 square feet, this can only be an estimate of what it does under normal conditions. If you’re using the AC to cool a server room that generates a lot of heat, the same BTU capacity will probably only cool an area of about 250 square feet. If you’re using the same AC to cool your home, you’re going to be more within the specified range of 400 square feet.
So you need to look at the BTU capacity in the context of how you plan to use the air conditioner. The amount heat producing equipment and people per square foot will determine the BTUs needed to control the temperature. Cooling will always require a greater BTU capacity than heating. This is because heat is always added to the room by people and the equipment that we use. Because we add heat to the room by our presence there, less heat needs to be added in order to keep the temperature comfortable.
Heating specs can often be expressed in kilowatts, this is the amount of heating energy or calorific value of the heating apparatus. To translate heating kilowatts into BTU we can, as a rule of thumb, convert 1000W of heating into 400-500 BTU.
Because of the cost of electricity and environmental concerns, knowing the energy efficiency of your air conditioner can be important. A rating system known as the Energy Efficiency Factor (EEF) has been developed. This a numeric grade representing the ratio between the energy produced by an appliance and the energy consumed. A higher rating means that the appliance has better energy output ratio and will use less electricity than an equivalent appliance with a lower rating. An air conditioner with an EEF of 10 is considered to be good, higher than this is even better. Not all manufacturers give the EEF of their appliances, but where this is available, it can help you consider your running costs and your environmental impact.
Saving on Air Conditioning Costs
An average air conditioner uses more than 1000W of electricity to run, so reducing your electricity consumption can save you a lot of money when using an AC. Apart from choosing a more energy efficient unit, there are a number of ways that you can use your air conditioner more effectively to reduce your running costs.
Insulation is key to controlling the environment inside a building. Brick houses have really good insulating properties. Wood frame buildings need extra insulation and fair better with good insulation materials inside the walls. Aluminum siding also helps a lot.
Double glazing is a big benefit in any building. The air cushion between the glass panels creates a barrier between the air inside the room and that of the air outside. Of course, we’re not going to rebuild our homes in order to cut down on our cooling costs but there are a few measures that we can implement.
Ceiling insulation is easy and hassle-free to retrofit. If your home does not have a well-insulated ceiling, installing insulation will save a heap on heating and cooling costs. Planting deciduous trees close to your house will help by shading the home in winter and allowing the sun to warm it in winter.
Airflow into and out of the room is a big factor. You want to keep the air conditioned air inside the room and prevent hot or cold air from entering the room. Keep the windows closed, the air intake pipe of the air conditioner will provide the right amount of fresh air to keep it healthy. In addition to this, most air conditioners have filters that improve the quality of the air entering the room.
If the window attachment for the intake/exhaust pipes of your air conditioner doesn’t fit properly, you’ll have a gap that will cause valuable air to escape. While these attachments are made to adjust to most window sizes, you may find that some windows are just too large or the shape doesn’t match. If this is the case, the window adapter will need to be modified. You can use flexible plastic or plywood to close the gap and ensure an airtight fit.
Sunlight entering a room will heat it, therefore, controlling the effect sunlight will help keep the room cooler. Aluminum blinds are the best for this.
Aluminum is a poor conductor of heat and will, therefore absorb less heat from the sun’s rays. Even with the blinds open, they will reduce some of the effects of sunlight. Closing the blinds will have the best effect, eliminating sunlight from entering the room. Keeping the blinds closed all day may be a little excessive, not many of us want to sit in a dark room during the day. Even turning the blinds to a slight tilt will reduce the amount sunlight baking the room while still leaving enough light to see by. So you can save by installing aluminum blinds and keeping partially closed.
Take a look at this infographic at Energy.gov to learn how an air conditioner works cools your home.