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Misconceptions About Whole House Dehumidifiers

If you're considering a portable dehumidifier over a whole house dehumidifier, you've probably done some research and you may have run into some of the following common misconceptions.  We'll help explain the origins of these myths, and also why they are simply not true.

Myth #1: Whole House Dehumidifiers are more expensive than portable dehumidifiers

Whole house dehumidifiers are bigger and are certainly priced higher than off-the-shelf portable models - the average price for a whole house dehumidifier is between $900 and $1200, while portable dehumidifiers will run from $100 to $300.  Whole house dehumidifiers are larger and have bigger fan motors and compressors and they typically use more electricity when they are running.  So how can they be less expensive to own than a portable unit?

In dissecting this myth, the first thing you must understand is how portable dehumidifier capacity is rated.  If you've looked through our list of whole house dehumidifiers (or anyone elses list for that matter), you'll notice that whole house models have two capacities: capacity at AHAM and capacity at saturation.  Portable dehumidifiers, on the other hand, only have one capacity rating - saturation.  Whole house dehumidifiers disclose performance at maximum humidity levels (saturation) and at typical humidity levels (AHAM).  Portable dehumidifiers only disclose performance at saturation which makes their capacity appear significantly higher than the performance you will actually receive.  At saturation humidity is at its peak and is very easy to extract from the surrounding air.  Unless your house is flooded, saturation conditions will not exist in your home.

Understanding the capacity of portable dehumidifiers is important because it really leads to the heart of this myth.  In most cases a portable dehumidifier will run constantly because it is too small to effectively dehumidify anything but an average sized room.  A whole house dehumidifier, on the other hand, can move a lot of air and extract significantly more moisture.  That means that a whole house dehumidifier will get the humidity levels down fast, and then stop running until the humidity increases again (and then it will run briefly, and repeat as necessary).  So even though the whole house dehumidifier is bigger and uses more electricity, it will be running much less than the portable dehumidifier.  The following table should illustrate the differences in operating costs between a very popular portable dehumidifier and a very popular whole house dehumidifier.

  Price 1 Year 2 Years 3 Years 4 Years 5 Years Total
Portable Dehumidifier
Danby DDR586R
$216.74 $332.44 $332.44 $332.44 $332.44 $332.44 $1,878.94
Whole House Dehumidifier
Santa Fe Classic
$1,195.00 $57.09 $57.09 $57.09 $57.09 $57.09 $1,480.45

The above comparison uses the following assumptions:

  • The portable dehumidifier is a 759 watt device (6.6A * 115V)
  • The whole house dehumidifier is a 782 watt device (6.8A * 115V)
  • The portable dehumidifier runs constant for 6 months of the year
  • The whole house dehumidifier will run 4 hours a day for 6 months of the year
  • The cost per kWh of electricity varies greatly across the US, but we used an average of $.10/kWh
  • In 2007 the cost of residential electricity ranged from $.0821 - $.2054 per kWh across the US (US Department of Energy)

Myth #2: Whole House Dehumidifiers are hard to install

If you've spent some time researching whole house dehumidifiers you will probably have encountered some elaborate diagrams illustrating ways you can integrate a whole house dehumidifier into your existing HVAC system. That does look like a lot of work and would be a quick turn-off for anyone not willing to perform that level of installation.

Fortunately, whole house dehumidifiers work just fine without any fancy ductwork or ventilation. All of our whole house dehumidifiers can operate as standalone equipment, which means you can simply plug it in and go.

The only other necessary step to complete installation is to run the drainage line. Portable dehumidifiers use buckets to hold the collected moisture (which have to be emptied frequently or the dehumidifier won't work). Whole house dehumidifiers drain the condensate into a tube, which you can run into your sump pump or floor drain. If you need to run the drain line into a utility sink or out a crawlspace window, then you should choose a whole house dehumidifier that has a built-in pump to push the water up the drainage hose (or purchase an optional external pump).

The truth is that whole house dehumidifiers require just as little installation as your average portable model. The difference is that a whole house dehumidifier offers much more flexibility if you want to integrate it into your HVAC system.

Myth #3: Whole House Dehumidifiers have special electrical needs

Many people assume that since whole house dehumidifiers are large that they might require special electrical attention (like hardwiring, or some special outlet). We do have a few industrial dehumidifiers that require 220V or 440V service, but those models cost more than $6000 and are not appropriate for residential use.

The truth is that every whole house dehumidifier that is appropriate for your home uses a standard 3-prong 115V plug and can be plugged into any standard electrical outlet in your home. Some of the more expensive models (typically commercial models) are recommended to be run on a dedicated 20A circuit, but the majority of our residential dehumidifiers will run just fine with no special electrical considerations.