What the best dehumidifiers have
- Large capacity. Experts say that in the majority of cases, the best humidifier will be the one with the largest capacity. That's true for even smaller spaces and more modest humidity problems as a large capacity humidifier will cycle fewer times and have larger condensate collection containers.
- Ample collection container. In all cases, the larger the collection container, the less often it will need to be emptied. This is not as much of a concern if you plan to drain the dehumidifier continuously via a hose. The only advantage of a smaller container is that it can be less of a load to lug if it's a bit of a distance between the dehumidifier and the sink.
- Multiple fan speeds. Portable dehumidifiers often have at least two fan speeds. The slower speeds are typically less noisy than the highest speed, but will wring out moisture more slowly.
- Automatic shutoff. Automatic shutoff deactivates the dehumidifier when the collection canister becomes full, an essential feature to prevent flooding.
- Automatic defrost. When used in cooler spaces, the coils in dehumidifiers can frost up, rendering the machine useless. Auto defrost helps to thaw the coils without human intervention.
- Full-container indicator. Without an indicator light, it can be hard to be sure if the dehumidifier isn't running because the container is full or if it's because it's between cycles.
- Automatic restart. In the event of a power outage, auto-restart will reactivate the machine once power is restored. This is a valuable feature for those using a dehumidifier in a property where someone might not always be present, such as a vacation home, or when the dehumidifier is installed in a relatively inaccessible location, such as in a tight crawl space.
- Cold temperature operation. Depending on where you intend to use the dehumidifier, you'll want to choose a model that operates effectively at the lowest temperatures it will be exposed to. Unfinished basements and crawl spaces, for instance, tend to have lower temperatures than finished basements or main living areas.
- High efficiency. Dehumidifiers that are Energy Star qualified operate more efficiently than non-Energy Star models. If you're dealing with an area with high humidity and will be running the appliance often, Energy Star-qualified models will save you money on electricity. In addition, local utility companies sometimes offer rebate for purchasing an Energy Star product, including dehumidifiers. You can find a list of current rebates at the Energy Star web site.
- Solid warranty. Be mindful of warranty options when purchasing a dehumidifier. In general, dehumidifiers last a few years, although malfunctions are possible. For portable dehumidifiers, standard warranties are for one year, though some components, such as the sealed compressor system, might be covered for longer.
Know before you go
How large is your space? Before you buy a dehumidifier, you'll need to know the size of the space you intend to use it in. This is particularly important for crawl spaces, where some units may not fit. Dehumidifiers vary significantly in the square footage they can effectively remove adequate moisture from, so choose a model with sufficient coverage, or consider buying two units.
Will you want to move the dehumidifier? Sometimes, consumers purchase a dehumidifier that they plan to rotate through different areas of the home. If this is the case, heavy models aren't the most practical option. Consider where you'll be using it, whether you'll need to relocate it up or down flights of stairs and whether the dehumidifier you're considering is designed to be permanently or semi-permanently configured in one place. Many, though not all, portable dehumidifiers have casters that can make moving them around on the same level a little easier.
How high a capacity dehumidifier do you need? The simple answer is to buy as big a dehumidifier as you can afford. Bigger capacity dehumidifiers can handle a wider range of humidity issues without constantly cycling on and off, which adds wear and tear to, and subtracts usable lifetime from, the appliance.
Can you kick the bucket? Whether the collection container is large or small, and regardless of how often or seldom you need to empty it, doing so isn't a fun job thanks to its weight when full and the occasional slosh or spill. Most portable dehumidifiers let you hook up a hose instead to continuously empty the moisture it captures into a floor drain. Some have a pump that will let you dump the water into a sink or out the basement window -- but experts say that, at least currently, the better solution is to buy a top-rated dehumidifier and opt for a third-party pump instead. Whole-house and basement dehumidifiers have no bucket at all -- condensate is emptied via a hose, again with pumps generally available either from the maker or from third parties.