What is a humidistat?

Any home has a thermostat, which controls the heating and cooling equipment in your home, and just like a thermostat, a humidistat is a controller for your in-home humidity level. It operates as part of your home comfort system by communicating directly with your humidifier to operate when a desired humidity. Usually located either by your thermostat or mounted to the cold air duct work on your furnace, it is simplistic in its features. Most humidistats are controlled by a setting the dial on the unit to the desired humidity level. The unit itself contains a sensor that reacts to moisture in the air which in turn activates the humidifier when the humidity level drops below the set point, maintaining the comfort throughout the home.

How To Use A Humidistat

Just like thermostats, when it comes to a humidistats performance, location is everything. There is a reason that they are typically located near a thermostat. It’s not for convenience’s sake, believe it or not. Thermostats are located in temperature neutral locations, where they are subjected to fewer factors that may throw off their readings (eg. sunlight through windows, common areas where body heat may build up, or close to high humidity areas like kitchens or bathrooms). Alternatively, installers may just mount them to cold air duct work in the basement, as they don’t typically require constant adjustment and can get an overall humidity reading directly from the air being moved throughout the home in the ductwork itself. Most humidistats are simple dial controls, just turn it to the level you want and let the system do the rest. Some may have digital displays, but the same rule applies.

The common problem is: What should it be set to? And that depends on your comfort level and the demands of the home. The increments on the humidistat represent the percentage of humidity in the air. If you find the home dry, turn it up another 5-10 percent and wait a few hours. If the air still feels dry, repeat that step. Low humidity not only affects the feeling of the air, but it makes air feel cooler, and creates physical discomfort in the form of dry skin, eyes, nose and throat. Too much humidity, on the other hand can be just as uncomfortable. High humidity can be immediately diagnosed if you notice condensation on you windows. But if there is no condensation, you may still notice the air feels thick, warm and generally uncomfortable. If that is the case, locate your humidistat and lower it 5-10 percent to see if it remedies the situation. High humidity levels are important to fix as they come with a host of household problems, including mold, rot, and warping of hardwood cabinets and floors.

Do I need a humidistat?

The answer largely depends on what type of HVAC system you have. While humidistats are a common feature in many systems today, with the rise in popularity of ‘smart thermostats’ and modulating and interlocked systems, they may quickly become a thing of the past. Smart thermostats can control every feature of home comfort and air quality that in most systems might require at least three separate controls. Not only are Smart systems more accurate down to the exact percentage, but they are more efficient and consistent in their delivery of the ideal level of comfort. A quick call to your HVAC contractor can tell you whether you need a humidistat in your home.