Desiccant or compressor dehumidifiers – do you know which one to choose for your home? Read our guide before you buy a dehumidifier so you know the pros and cons of each type.
What does a dehumidifier do?
The perfect antidote for a moist, dusty or musty indoor environment is a dehumidifier. The primary function of a dehumidifier is to reduce the amount of humidity in the indoor air but this comes with plenty of secondary benefits such as the removal of dust mites from the atmosphere, reduction in the amount of condensation and an overall improvement in the indoor air quality.
If you are getting miserable from allergic reactions, perhaps it’s time you invested in a good quality desiccant or compressor dehumidifier, especially if you live in a fairly humid climate such as in the coastal areas.
A desiccant or compressor dehumidifier will help eliminate some of the common triggers of allergic reactions such as mold, mildew and dust mites. This can be particularly advantageous for people suffering from seasonal allergies.
A dehumidifier can also come in handy if used in small or confined spaces with poor ventilation such as in the kitchens and bathrooms. Ideally, these should be built with optimal ventilation that takes out the warm moist air and brings in cool dry air through a convection process.
However, this is not always the case as the convection cycle may not be as efficient as to totally eliminate the moisture or humid air from the space. In these instances, it may be more prudent to bolster the natural convectional process with some artificial dehumidification mechanism that helps get rid of most of the moisture in the spaces and prevent a moisture buildup.
A desiccant or compressor dehumidifier will help achieve the following:-
- Dehumidifiers help in cutting down the humidity levels in indoor spaces, thus making these spaces less conducive for allergens such as mildew, mold and dust mites.
- The use of a desiccant or compressor dehumidifier will help minimize bad odors that are associated with a more humid environment and the presence of allergens. They are particularly effective in eliminating the musty smell that occurs in a moist indoor space.
- They inhibit the growth of molds.
- By boosting the indoor air quality, they help reduce the irritations on the skins or respiratory systems that are associated with allergens and a moist environment.
- They minimize the level of dust in your indoor spaces.
- A less humid indoor environment has other secondary benefits. For example, clothes will dry faster, mold does not easily form on stored food and there is less corrosion on metallic surfaces.
How to tell if you need a desiccant or compressor dehumidifier
You are likely to need a desiccant or compressor dehumidifier if you are highly sensitive to some of the common allergic triggers such as dust, allergens or bad odor in your premises. If some rooms have obviously high levels of humidity, you may also need to acquire a desiccant or compressor dehumidifier to clear the backlog and ensure the integrity of the surfaces on your premises. Signs of high humidity in an indoor space can include the following:-
- Water stains on indoor surfaces such as ceilings and walls.
- A musty smell or a mildew smell.
- Little black spots on some parts of the walls or bathtub. These are generally signs of mold spores wrought about by high levels of humidity in the air.
- Condensation on metallic surfaces in the room, particularly on the window panes.
- High levels of humidity inside rooms that have poor ventilation.
Keeping your rooms clean is often not enough. If it is not sufficiently ventilated, there will be a build-up of moisture that eventually opens a Pandora’s Box of moisture-related issues that can be a health hazard to you and your family.
How to choose between a desiccant or compressor dehumidifier
There are different types of dehumidifiers that you can use to extract the moisture in your indoor air. Generally, there are two types of competing dehumidifier technologies… namely, the compressor dehumidifiers and the desiccant dehumidifiers.
The compressor dehumidifiers are the legacy dehumidifier types and are also the most popular with many users. For the past four decades, this has been the default dehumidifier technology in the market.
They use the condensation mechanism to extract water from the atmosphere. Basically, the compressor dehumidifier draws in warm damp air and passes it over a refrigerated coil and then condensation occurs when warm humid air comes into contact with the cold surface. The surface is cooled by a refrigerant. Water is thus separated from the air in this way. The condensed water is then channeled into a tank and later on disposed of. The dry air is reheated to room temperature via a warm coil and released back into the room. The compressor dehumidifiers generally work best in environments with high ambient temperatures.
Advantages of Compressor Dehumidifiers
- They work well in warm climates: The compressor dehumidifier has to be colder than the surrounding indoor air in order to work effectively so in warm climates, they are highly effective in getting rid of the moisture from the air. They are generally recommended for temperatures above 15°C.
- Help maintain the room temperature: Because the compressor humidifiers reheat the de-humidified air back to the room temperature before blowing it back into the room, they can be great for environments where the room temperature needs to be maintained such as in wine cellars. However, they don’t “re-heat” the air by much. Usually, the compressed air is just 1°C to 2°C warmer than the ambient room temperature.
- Low energy consumption: Compressor dehumidifiers consume less energy per hour and are thus generally cheaper to run.
Disadvantages of Compressor Dehumidifiers
- Not suited for cold climates: Because the compressor dehumidifier has to be colder than the surrounding air to condense the water in the damp air, it will have to work extra hard to dehumidify a very cold room. If temperatures drop below 15°C, the compressor dehumidifier temperatures will tend towards the freezing point and this will lead to the formation of ice on the dehumidifier coils. As a result, in cold temperatures, the compressor dehumidifier spends close to 67% of its time and energy defrosting its coils rather than dehumidifying the air and this leads to a very inefficient operation.
- They are bulkier: Compressor humidifiers are generally heavier, typically weighing over 10kg. They are also less compact and are better suited for an application where you are not dehumidifying a very big house or multiple levels. This is in contrast to desiccant dehumidifiers which are lighter and portable and can be carried to multiple rooms and levels.
- They are noisy: Compressor dehumidifiers are generally noisier with a fan noise of about 40 decibels in most models.
While a compressor dehumidifier has a compressor and a cold surface that it utilizes to yank the moisture from the damp air, the desiccant dehumidifier works more like a sponge or silica gel, simply absorbing the moisture from the humid air via a desiccant wheel. The wheel is regenerated by an inbuilt internal heater that allows the process to go on and on.
The desiccant dehumidifiers are generally quieter and more compact in design and are thus preferred by many customers. Below are some of the pros and cons of using a desiccant dehumidifier:-
Advantages of Desiccant Dehumidifiers
They work well in both cold and warm climates: Unlike the compressor dehumidifiers that are really built for a warm ambient temperature, the desiccant dehumidifiers will maintain a superior standard of performance in both warm and cold ambient temperatures. This is because while the compressor dehumidifiers work on a condensation principle that requires a temperature gradient between the atmosphere and a condensation surface, the desiccant dehumidifiers utilize an adsorption principle where the water molecules adhere onto a surface to form a thin film of moisture on the dehumidifier material. This makes them highly effective as dehumidifiers in spaces with high humidity at low temperatures. As a result, with the desiccant dehumidifiers, you don’t have to grapple with the 15°C “cut-off” room temperature for optimal performance that is required for the compressor dehumidifiers.
Desiccant dehumidifier vs Compressor dehumidifier extraction rate based on temperature
- Desiccant dehumidifiers can keep your home warm during winters: While both dehumidifiers warm the air that passes through them before releasing it back into the room, they differ in terms of the degree of heat generated. The desiccant dehumidifiers offer a superior performance in this regard in that they offer a better heating performance. In the compressor dehumidifiers, the dry air being pumped out will be about 2°C warmer while in the desiccant dehumidifier, the dry air coming out will be about 3° to 5°C warmer. If you are looking for a dehumidifier for use in a chilly room or cold weather, the desiccant type would make perfect sense. In a warm room or warm weather where you may wish to maintain the same room temperature, you can go with the compressor type.
- Low noise levels: Because they are not built with a compressor, the desiccant dehumidifiers are generally quieter in operation.
- Optimal energy consumption in cold weather: The compressor dehumidifiers are generally cheaper to run in warm weather but the desiccant dehumidifiers make more energy sense in cold weather. Not only do they dry the damp air, they also release warm heated air into the room without much energy expenditure. It is like killing two birds with one stone.
- Portable: The desiccant dehumidifiers are generally lighter and more compact than the compressor dehumidifiers. On average, they weigh anywhere from 5kg to 9kg compared to the compressor dehumidifiers that weigh over 10kgs with few exceptions. While a single dehumidifier is generally sufficient for a home as long as the doors inside the house are open, you might need to move the device from one position to another or one level to another and in those instances, a desiccant dehumidifier will come in handy in delivering an optimal dehumidifying performance on your premises.
- Low maintenance: Unlike the compressor types, the desiccant dehumidifiers do not use any refrigerants and are therefore easy to maintain.
- They are more durable: Due to their simpler mode of operation which does not include a compressor, a refrigerant or numerous moving parts, the desiccant dehumidifiers tend to have a longer lifespan.
Disadvantages of Desiccant Dehumidifiers
- They are more expensive: While there are cheaper desiccant dehumidifiers in the market, they generally tend to be more expensive than the compressor types.
- In warmer temperatures, you can be better off running a compressor dehumidifier which is not only cheaper to run, but also helps in maintaining the room ambient room temperature.
Both desiccant or compressor dehumidifiers are great!
As we've discussed above, both types of dehumidifiers have their strong points and weak points.
The desiccant dehumidifiers tend to have an edge in many applications. They are very versatile and many consumers now prefer them, especially as they work better in both cool and warm climate. Desiccant dehumidifiers are the recommended model in areas such as Victoria and New South Wales that experience warm winters and cold summers. Check out the range of desiccant dehumidifiers below:
However, the compressor dehumidifiers are still preferred in many environments, especially in areas that are hot all-year round such as Queensland, the Northern Territory and Western Australia. If this sounds like you, you'd benefit from a compressor dehumidifier like the Ionmax ION622. Check it out below:
At the end of the day, you should choose a dehumidifier that will match your preferences based on the above considerations as well as your budget for the dehumidifier.
Need help with buying a dehumidifier? Contact us for assistance!
Want to learn more? Check out our video on How Desiccant Dehumidifiers Work and their Benefits compared to Compressor Dehumidifiers below:
Healthline, "How a dehumidifier works", https://www.healthline.com/health/dehumidifier-benefits#how-it-works
Choice Reviews, "How to buy a dehumidifier for your home", https://www.choice.com.au/home-and-living/cooling/dehumidifier/buying-guides/dehumidifiers
Wired Shopper, "Dehumidification Technologies: Basic Methods and Emerging Trends", https://thewiredshopper.com/dehumidification-technologies-emerging-trends/
Which.co.uk, "How does a dehumidifier work?", https://www.which.co.uk/reviews/dehumidifiers/article/how-does-a-dehumidifier-work-aynpr9t2A2ku
Service Champions Heating and Air Conditioning, "4 Different Types of Dehumidifiers and How They Work", https://www.servicechampions.net/blog/types-dehumidifiers-how-they-work/
Note: This post has been updated for accuracy and product information in January 2021.