Getting the right size for your room is absolutely essential when choosing a dehumidifier. The dehumidifier size refers to the maximum amount of moisture it can remove within 24 hours, typically measured in pints. The standard compressor dehumidifiers available today range from 20 to 50 pints. This is not to be confused with the dehumidifier’s water tank size, another important factor to consider when you purchase a unit.
Generally, a higher capacity dehumidifier comes with a bigger water collection bucket, but it can vary depending on the brand and model. Large dehumidifiers can extract huge amounts of moisture from high humidity areas in your home such as the basement. By default, this is collected in the water bucket, which you need to empty manually. The larger the tank, the less frequently it will fill up. Thus, the tank capacity should be one of your considerations along with other drainage options for your dehumidifier.
How Are Dehumidifiers Sized?
First, you must understand how dehumidifiers get their pint ratings. Manufacturers indicate the rated capacity of each dehumidifier according to the current testing standards set by the Department of Energy (DOE).
Starting from 2012, dehumidifiers were tested at 80°F and 60% humidity. However, as of early 2020, dehumidifiers have new ratings based on the new DOE standards of 65°F and 60% humidity. The change in the temperature standard gives a more accurate representation of the dehumidifier’s performance in a typical basement. Thus, previously rated 30-pint, 50-pint, or 70-pint dehumidifier is now labeled as 20- or 22-pint, 30- or 35-pint, and 50-pint dehumidifier, respectively. You can find the Energy Star dehumidifier sizing chart here.
While the ratings for the moisture removal capacity have changed, the unit itself is still exactly the same. This includes the water tank size and all other features of the dehumidifier.
What are the Common Water Tank Sizes for Dehumidifiers?
What most people are familiar with is the compressor-based residential dehumidifier. This type of dehumidifier often ranges from 20 to 50 pints in capacity. It comes built with a collection tank or bucket located in the bottom part of its plastic housing to hold the moisture collected from the air. The water bucket is often on the front or side of the unit with a transparent window so you can see the water level, and a handle you can grip when removing the tank and emptying the water.
The tank size mainly depends on the dehumidifier capacity—the larger the dehumidifier, the larger the tank. For example, a 30-pint dehumidifier has a smaller tank than a 50-pint and this is evident in the physical dimensions of each unit (see image below).
After the changes in dehumidifier pint ratings, the highest capacity rated by DOE and Energy Star is 50 pints. Although, some brands still advertise 60-pint or 70-pint units, like the Frigidaire FFAD6022W1 model. On average, these large dehumidifiers have water tanks that can hold 14 to 16 pints or 1.75 to 2 gallons.
For example, the Honeywell TP70WK and the Frigidaire FFAD5033W1 models. Those with smaller tanks have a capacity of 12 pints or 1.6 gallons (BLACK+DECKER BDP50MWSA) while the largest can hold up to 18 pints or 2.25 gallons (Ivation IVADH50PW).
For 30- to 35-pint models, the range of tank capacity is wider, from 7 to 14 pints on average. The unit itself is often built with a similar size (and thus the same tank capacity) to the 50-pint version. This is the case with Frigidaire FFAD3533W1 and hOmeLabs HME020006N, which feature 16.9-pint and 12.8-pint water tanks, respectively.
Meanwhile, other brands manufacture 30- or 35-pint dehumidifiers similar to their 20- or 22-pint counterparts. One example is the Honeywell TP50WK 30-pint dehumidifier with a small 7-pint tank.
Dehumidifier Tank Capacity
In the following table, we compare the tank capacity of some of the popular Energy Star certified dehumidifiers for each size range.
|20-22 pint unit||30-35 pint unit||50-pint unit|
|BLACK+DECKER||6.4 pints||6.4 pints||12.68 pints|
|Frigidaire||9.1 pints||16.9 pints||16.9 pints|
|GE||6.4 pints||14.4 pints||8.8 pints|
|hOmeLabs||6.4 pints||12.8 pints||12.8 pints|
|Honeywell||7 pints||7 pints||14 pints|
|Keystone||6.4 pints||12.8 pints||12.8 pints|
|Vremi||6.4 pints||12.8 pints||14.4 pints|
These dehumidifiers have a float switch on top of the water tank that signals the unit to stop operation when the water level in the tank reaches a certain height. This automatic shut-off is a critical feature in every dehumidifier to prevent water overflow and ensure the safety of the unit. Once shut off automatically, the unit will only resume operation when the tank is emptied and put back into its proper place. Meanwhile, the dehumidifier will not be removing moisture and the humidity level may increase again the longer the unit is off.
For example, you run a 50-pint dehumidifier continuously for 24 hours and you remove the tank and empty the water every time it fills up. With a 12-pint tank, you will need to do this at least four times per day. On the other hand, if your dehumidifier has a 16-pint tank, you’ll only need to do this three times per day. While it’s not a particularly difficult task, it can still be a hassle for you, especially if the unit is in a different room or when you need to leave. Thus, the larger the tank, the more convenient it is for you.
Another dehumidification method that dehumidifiers use is the Peltier effect or thermoelectric cooling wherein a voltage of electricity creates a temperature difference in the Peltier module. It works almost similar to a compressor dehumidifier but the main difference is it consists of a Peltier module and two heat sinks instead of a compressor and metal coils.
Compared to the standard compressor units, a Peltier dehumidifier has a much smaller capacity, usually between 8 to 25 ounces (250 to 750 ml). However, its water tank is large enough to hold two days up to a week’s worth of moisture, from 16 ounces for the smallest units up to 68 ounces for the largest, or 500 ml to 2 liters. This means you only need to empty the water after a few days instead of multiple times in one day. These units also feature auto shut-off so you don’t need to worry about spilling water in case you leave your unit running.
Whole-house and Commercial Dehumidifiers
If you want a single unit that can handle larger spaces or your entire home, then you should look for a whole-house dehumidifier. These units are often installed in the crawl space or basement or anywhere you can connect them to your HVAC system. For commercial or industrial spaces that produce a lot more than 50 pints of moisture a day, then you need a heavy-duty dehumidifier with a capacity starting from 70 pints up to 200 pints and beyond. These high-capacity dehumidifiers for whole-home or commercial applications usually don’t collect the condensate in a tank. Instead, they come with a drain hose or condensate pump that automatically drains the water.
If size or noise is a real issue for your space, a desiccant dehumidifier can be a great alternative to typical refrigerant dehumidifiers. Desiccant models use a different mechanism of moisture removal that makes them suitable for lower temperatures. Residential desiccant dehumidifiers are similar in appearance to small compressor dehumidifiers, with a capacity of 10 to 20 pints. The water tanks are accordingly sized, from 3 to 6 pints capacity. However, more commonly used are the disposable and rechargeable types of mini desiccant units. You can read more about this type of dehumidifier in our detailed article here.
What Size Dehumidifier Do I Need?
Whether you choose a 30-pint, 50-pint, 70-pint, or bigger dehumidifier depends on a few key factors like relative humidity, temperature, and the square footage of your living space. Homes in a humid climate or areas with more humid air such as crawl spaces will need higher total moisture removal capacity. A smaller room like a laundry room can get by with a smaller size dehumidifier with a smaller water tank capacity. Moderately damp or extremely wet spaces may need even more capacity. Check out our complete guide here to find out how big a dehumidifier needs to be to make sure the amount of moisture removed meets your needs. This dehumidifier size table will help guide your decision.
Keep in mind that during summer or if you’re in a warm climate, an air conditioner can also help to reduce the relative humidity levels in your space. This is because air conditioners remove moisture out of the air as part of the process that they use to cool down the air.
How Much Water Should a Dehumidifier Collect in a Day?
The total volume of water a dehumidifier collects in a day depends on its capacity.
On average, 20-pint dehumidifiers can collect about a gallon or two (8 to 16 pints) of water, while the largest can collect up to six gallons (or 50 pints). However, the actual amount it will collect per day depends on many other factors, most importantly, the room size, air temperature, and relative humidity.
The larger the tank, the more water it can collect before the unit shuts off and you need to empty the water. If operating in huge, damp spaces like a basement, then a larger tank is always better. Although, no matter how big the tank your dehumidifier has, always remember to empty the water immediately as standing water can encourage mold growth and dust mites.
However, if you don’t want to do the work, most dehumidifiers offer options for continuous drainage through a drain hose or pump. We discuss these drainage systems in detail in the article on how to drain a dehumidifier.
As you can see, the tank capacity is an essential feature in a dehumidifier, especially if your room has no available drain or sink for a drain hose. While a larger tank is better, it is still more important to get the correct dehumidifier size for the space. Measure the length and width of the room and multiply them to get the square feet area. Compare this with the range of coverage areas the manufacturer recommends for each dehumidifier model. Find the right dehumidifier capacity based on the room size and condition, then choose a unit with a slightly larger tank to allow for some buffer.