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The IAQ market experienced a boom in the past year, largely as a result of the coronavirus. Homeowners looked to improve the safety of their indoor spaces, and commercial building owners wanted to be sure that employees and customers were kept healthy.

Humidity control makes up an important facet of indoor air quality, a facet that includes reducing airborne viruses but extends far beyond it. The HVAC industry has a vital role to play in the humidification market, and technology has been developing to meet the market’s latest needs.


Humidification’s Impact on Homeowners

Mindy Wetzel, senior product manager – humidifiers, Aprilaire, explained that the importance of humidity control in living spaces has to do with health, comfort, preservation, and energy savings.

“Proper humidity helps to keep families healthy by reducing the airborne incidence of bacteria, viruses, fungi, and dust mites that can cause respiratory infections and symptoms related to allergies and asthma,” said Wetzel. “In addition, keeping humidity between 40-60% can minimize virus transmission rates.”

Proper humidification can limit static shocks in a home and reduce uncomfortable ailments like itchy skin and bloody noses. This can also benefit the wallet — proper humidity makes a home feel warmer, meaning the thermostat can be set lower to save on utility costs. It can also help preserve a property’s value. Improper humidity can damage musical instruments, wood floors, and crown molding. Bowing and cracking can occur, which can be expensive to repair or replace.

“Too much humidity can produce mold, mildew, warped wood, and higher insect populations,” said Paige Freeland, marketing manager, General Filters. “Fabric in bedding and clothing can feel damp and clammy. Maintaining consistent humidity indoors helps protect your health, home, and assets.”


Trending Technology in Residential Humidification

According to Freeland, several trends are sweeping into the humidification market. People are leaning on smart technology, which can allow them to control their entire suite of humidification and IAQ equipment through one device. More and more people are realizing the value of whole-house humidity as opposed to room-based solutions.

Steam humidifier.

STEAM HUMIDIFIER: General Filter’s Freeland said that steam humidity is becoming a popular option for homeowners. (Courtesy of General Filters)

Freeland said that steam humidity is becoming a popular option, too, as is using dehumidification equipment alongside air conditioning to preserve ideal humidity while also saving money on cooling the home.

“There are two usual sources of whole-house humidification: bypass/evaporative-style humidifiers and electrode technology steam humidifiers,” said Freeland. “The first solution is the most economical to install and maintain, while the second provides superior service at an increased cost.”

In choosing a humidification solution for a home, contractors should base the selection on the size of the home and any items that may need protection. Wetzel recommended installing units with automatic controls so that the products can adjust to outside temperature changes while still maintaining the optimal humidity set up at installation. Freeland even recommended slightly oversizing the humidifier, which would ensure that the equipment is not overtaxed if the homeowner installs hardwood floors or expands their home.

“Perform maintenance as recommended,” said Freeland. “For an evaporative humidifier, it is imperative that the vapor pad be replaced at least once annually and that the humidifier is clean of residue. A steam humidifier requires the annual replacement of the water cylinder. Cleaning and reusing the cylinder is not recommended.”

Important questions to ask homeowners when sizing and selecting a humidifier include inquiring about the square footage of the home, ceiling heights, fireplaces, remodeling plans, and any special rooms (such as humidors or wine cellars) that may require a specialized humidity set point. Certain aspects such as expansive square footage, wood surfaces, health concerns, or specialty uses may mean that steam is a better humidification choice than evaporative humidity.


Commercial Humidification and Production

Similar to residential settings, ideal humidification control in commercial buildings means a safer and healthier area for occupants to reduce the risk of illness transmissions, skin dryness, and eye irritation. Improper humidity can also lead to the costly loss or degradation of products. Materials that readily absorb and store water are especially vulnerable. That category includes products such as foods, textiles, carpet, wood, paper, leather, and plastics.

“Fluctuating and low relative humidity levels contribute to a number of problems in commercial buildings,” said Valerie Bradt, marketing communications manager, DriSteem. “Changes in humidity levels not only have a direct impact on material stability but may have an indirect impact on production processes such as printing, packaging, pharmaceuticals, and electronics manufacturing.”

Improper humidity control can also damage company infrastructure. Too much dry air can cause static electricity buildup that can damage electrical devices, machinery, printers, and circuit boards. In the worst cases, this can lead to production line disruptions or even failures. In lab settings and critical applications, a suboptimal humidity level can cause microbes and bacteria to contaminate research.

“Humidity is sometimes perceived as a bad thing for a building, but when properly controlled, it is essential for protecting against production disruptions or failures in labs.”
- Valerie Brandt
Marketing communications manager DriSteem

Trending Technology in Commercial

As interest grows in humidification in the commercial sector, the industry is seeing an increased focus on high-efficiency equipment and sustainability. Companies and schools are becoming much more aware of how IAQ affects the productivity and health of employees and students, respectively.

“Energy management and the analysis of energy data is a critical aspect of building management,” said Bradt. “As energy costs rise, it has become increasingly important to reduce energy consumption. Because of ongoing concern over carbon emissions and the environmental damage that they cause, emission standards and regulations are becoming increasingly stringent.”

When servicing commercial humidification equipment, the first step should be to take a relative humidity (RH) reading with a hygrometer. A target of 45% is typically seen as offering the benefits of good humidity while also being achievable.

If lower RH levels are being observed, check equipment to see if it is operating, and adjust/raise the set point if required. Technicians should also review the current space configuration and use. Spaces can change in the years after installation, so additional capacity/output may be needed. Humidification systems need to be sized precisely for the load of the building they service, so changes in the building use or configuration mean that the system’s output should be reviewed over time.

“For buildings that did not originally have humidification equipment and need to be retrofitted, supplementary humidification systems can be quickly installed on a wall and can start adding moisture to rooms right away,” said Bradt. “Larger humidification systems can be incorporated into a facility’s HVAC system, in the mechanical room, or on the roof, and can keep an entire building humidified.”

When maintaining humidifiers, technicians should work to reduce and remove any scale that builds up in the humidifier. Any extant scale can be removed with a descaling solution, and future scale can be prevented or drastically limited by using softened water.

“Humidity is sometimes perceived as a bad thing for a building, but when properly controlled, it is essential for protecting against production line disruptions or failures, loss or degradation of materials, inconsistent environmental conditions in labs and other critical applications, and negative effects on occupant health,” said Dristeem’s Bradt.


Commercial Humidification Options

There are two main methods of humidification for commercial applications: isothermal and adiabatic.

Isothermal (steam) humidifiers work by boiling water inside the humidifier tank and distributing it into the ductwork through a steam manifold or directly into the space.

  1. Gas-fired humidifiers: Lowest operating cost for a steam-generating humidifier, broad capacity range
  2. Electric resistive humidifiers: Broad capacity range, very accurate control capabilities
  3. Steam exchange humidifiers: Uses existing boiler steam as its energy source
  4. Electrode humidifiers: Maintenance is easy — simply replace the cylinder, lowest first cost

Adiabatic (evaporative) humidifiers use the heat in the air to evaporate water into the ductwork or directly into the space. Adiabatic humidifiers provide humidification and evaporative cooling at the same time. The choice of humidification system for commercial use depends on many factors, including the energy source available, capacity required, supply water, available space, and maintenance.