Features On Modern Dehumidifiers
When shopping for a whole house basement dehumidifier you will encounter many options that you may not be familiar with. Here are some of the most common, what they mean, and whether or not you need them.
Condensate Pump (or just Pump)
Sometimes gravity is all you need to move the water collected by the dehumidifier to a drain or sump pit. If your dehumidifier will be installed where there is no convenient access to adequate drainage, then you will need a condensate (or water) pump. A condensate pump simply pushes water so that you can extend a hose to the nearest drain. Some models have built-in condensate pumps, but an optional external condenstate pump can be added to just about any model on the market. Typically installing an external condensate pump is as easy as running a hose from the outlet of the dehumidifier to the pump, and then another from the pump to your drain or sump pit.
A humidistat is a device that compares relative humidity to a desired humidity level, and then turns the dehumidifier on or off if needed. Most of the high-end dehumidifiers have some sort of humidistat built-in. Some of the industrial and restoration dehumidifiers are meant to run all the time and do not need a humidistat (although optional humidistats are typically available). Many dehumidifiers can be controlled by a remote dehumidistat, but in most cases this is not necessary.
Ducting and Duct Collars
A dehumidifier works by pulling air in, removing moisture, and then exhausting that air back out again. Duct Collars are used to connect ducting to your dehumidifier, so you can create distance between the air intake and exhaust. This allows your dehumidifer to "breathe" moist air that is far away from the "dry" air that gets exhausted. Ducting your dehumidifier will generally improve the efficiency of the unit since no effort is wasted drying air that was recently exhausted and is already dry. It is important to note that ducting is not always an option, and many models are designed to work efficiently without additional ducting.
The operating temperature in the space where your dehumidifier is located plays a large role in how your dehumidifier works. Cold air is more difficult to extract moisture from and some dehumidifiers have a difficult time operating when the ambient air temperature is outside the operating range of the dehumidifier. In residential use you will likely only ever see problems with low temperatures (higher temperatures can store more moisture, which makes it easier for a dehumidifier to work). If you are planning to operate your dehumidifier in a space where the ambient temperature is low (less than 60° F) you need to make sure that the model you choose won't have any problems operating in that environment.
Most dehumidifiers use some sort of filter on the intake. These low quality filters are typically made of foam, and do an adequate job of preventing particle build-up on the vital dehumidifier components. Some dehumidifiers use a high-quality filter that allows the dehumidifier to double as an air cleaner for the space where it is installed. In either case you have to be sure that you keep your filter clean (if you have a foam or washable filter), or replaced as necessary. If the intake filter gets clogged, the dehumidifier will not be able to pull much air through the unit, which means it will not be able to extract much moisture from the air.