What Is a Dehumidistat?

humidistat is an electronic device analogous to a thermostat but which responds to relative humidity, not temperature. Humidistats are used in a number of devices including dehumidifiers, humidifiers, and microwave ovens. In humidifiers and dehumidifiers the dehumidistat is used where constant relative humidity conditions need to be maintained. They can save you money on your utility bill especially when you are away for extended periods of time.

What Does a Dehumidistat (or Humidistat) Do?

A humidistat regulates humidity levels inside a home or business. The terms Dehumidistat and Humidistat are often used interchangeably.

How Does a Dehumidistat Work?

Humidistats measure electrical resistance to relay to an amplifier that can turn the humidifier on or off until the ideal level of moisture is detected. A dehumidistat works almost like a humidistat but instead of closing, its electrical contacts open up when the room’s humidity level is lower than the controller’s setting. When the room’s humidity increases, the electrical contacts close .The dehumidistat will then work to lessen the room’s humidity by removing extra humidity from the air. A dehumidistat is also commonly used to get fans to control the humidity of the crawl space and offer ventilation.

How to Set a Dehumidistat

While dehumidistats are user-friendly, if you want to get the most out of your humidistat, it’s important to understand how to adjust the settings appropriately for your home. Read on to learn everything you need to know about dehumidistats.

How Can a Dehumidistat Save Me Money

This is one of those inexpensive ways to save money. Installing a dehumidistat in your home is particularly important when you tend to spend a lot of time away from it.

high humidity

Just like a thermostat, a dehumidistat turns you’re a/c system on and off depending on what the settings and what the environmental conditions are. While the thermostat’s “trigger” is temperature (your home’s temp rises and it turns on), the dehumidistat’s does the same thing with humidity.

It’s more important to control the climate in your home while you are away, rather than the temperature (there’s no sense in cooling the space if you are not there to enjoy it), the dehumidistat runs your a/c system until the air inside the conditioned space is below a certain humidity level.

So, why is it important to control that climate? If you simply shut off your air conditioner or set it to a higher temp, the lack of air circulation and rise in humidity combined can lead to the growth of microorganisms like mold. Running the air conditioner alone while cooling a large and unoccupied dwelling in Florida in July can also cost you quite a bit of money and be rather inefficient. By running your system to combat humidity, the dehumidistat can and will save you money on your electric bill, it will run your a/c system more efficiently sparing it the needless wear and tear and help extend the unit’s life.

Now is the time to consider contacting us at Bayside to install a Dehumidistat. It really is a great device that is inexpensive to install. The savings you incur will offset the cost of the device in a very short amount of time

What Should My Dehumidistate or Humidistat Be Set At in the Winter?

Living in Florida, we’re no strangers to humidity. After all, Florida is one of the most humid states in the country, with the daily average humidity level hovering around 75%. During the Winter months when humidity is lower you do not need to use the Dehumidistat.

What Should My Dehumidistate (Humidistat) Be Set at in the Summer?

Dehumidistat Settings When Away For Extended Periods: If you are going to be away from your home for an extended period (back up north in the summer for example), you can set your humidistat to use less energy. According to energy experts at Florida Power and Light, mold can grow in your home at 68 percent relative humidity, and some humidistat sensors can be off by as much as 10 percent. So to be safe, we recommend setting your dehumidistat’s relative humidity (RH) to 58 percent and setting your thermostat temperature between 77 and 80 degrees Fahrenheit. These settings will not maintain your selected temperature indoors but will maintain 58 percent humidity.

While everyone’s home comfort preferences will vary, we recommend a dehumidistat setting between 35 and 45 percent for Summer.

According to the EPA (Environmental Protection Agency), it is recommended that Florida residents keep the indoor relative humidity below 60% relative humidity. Ideally, that percentage should be between 30% to 50%. Half of the year this would certainly be attainable, but during those hot, sticky summer months it is more likely your home will not get lower than 55%-58%. This is assuming your air conditioning is running on a properly sized system without a whole home dehumidifier, as these are normal circumstances.

Setting your dehumidistat correctly during Florida’s extra hot and humid summers is important. Keep in mind that the goal of your humidistat is to keep the humidity in your home in a comfortable range. Since Florida summers are often more humid than other seasons, you’ll want to keep an eye on your device.

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