Automatic Humidity Control Systems: Comprehensive Overview

Having an automatic humidity control system to control the relative humidity in your home or workplace is important for many reasons. Depending on your requirements, there are different humidity controller solutions available.

Whether you are trying to control:

• moisture in the living and bedrooms of your home,
• kitchen and bathroom humidity, or
• more specialized needs such as for greenhouses, museums, or other commercial applications,

… here we discuss some of the options available to you.

But first, here is some of the background information that you may find useful…

What Is Relative Humidity?

You have very likely heard the term ‘relative humidity’ used in relation to weather and air quality information. Relative humidity (RH) is a measurement that reveals the amount of moisture being held in the air at a specific time. If the RH is 100%, this means the air cannot hold any more water (ie. it is saturated).

For a more detailed explanation of relative humidity, click here.

The higher the moisture content, the more humid the air becomes. For many with respiratory issues, high humidity makes the air difficult to breathe. Also, with all that moisture a humid room or house can be a perfect breeding ground for mold and mildew to develop and grow.

Bacteria growth in high humidity conditions is not only bad for our health; it is not good for a home. Wood, in particular, is susceptible to damage from excess moisture. Condensation can also form which can result in water staining, wallpaper peeling, and insect infestation.

Introduction to Automatic Humidity Control Systems

Automatic humidity control systems are innovative technological solutions designed to regulate and manage indoor humidity levels seamlessly. In environments where humidity can significantly impact comfort, health, and even the structural integrity of buildings, these systems prove to be indispensable.

Definition and Purpose

At their core, automatic humidity control systems are sophisticated devices that monitor the humidity levels within a space and adjust them as needed to maintain a predefined optimal range. They achieve this through a combination of sensors, actuators, and control algorithms. These systems can be integrated into HVAC (Heating, Ventilation, and Air Conditioning) systems or operated as standalone units, depending on the specific requirements of the setting.

The primary purpose of these systems is to ensure that indoor humidity remains within a balanced and health-supportive range. High humidity levels can lead to issues such as mold growth, allergen proliferation, and discomfort. On the other hand, excessively low humidity can result in dry skin, respiratory problems, and even damage to wooden furniture and musical instruments. Automatic humidity control systems mitigate these problems by consistently adjusting the humidity levels to create an environment that is conducive to human health, comfort, and the preservation of valuable items.

Benefits of Using Automatic Humidity Control Systems

1. Health and Comfort: Maintaining optimal humidity levels contributes to a healthier indoor environment. By preventing excess moisture and mold growth, these systems help reduce allergens and improve air quality. Additionally, maintaining comfortable humidity levels reduces skin dryness and respiratory irritation.
2. Preservation of Assets: Automatic humidity control systems are particularly beneficial for preserving valuable possessions. For instance, in museums, libraries, and archives, maintaining stable humidity helps protect artwork, rare books, manuscripts, and historical artifacts from deterioration due to fluctuating moisture levels.
3. Energy Efficiency: These systems optimize humidity levels while minimizing energy consumption. They ensure that humidification or dehumidification processes are only activated when necessary, leading to energy savings and reduced utility costs.
4. Structural Integrity: In homes and commercial buildings, excessive humidity can lead to structural issues like warping of wooden components and corrosion of metal fixtures. By controlling humidity levels, these systems contribute to the longevity of the building’s materials.
5. Automation and Convenience: Automatic humidity control eliminates the need for manual adjustments. Once the desired humidity range is set, the system operates autonomously, freeing occupants from the hassle of constant monitoring and adjustments.
6. Customization: Different environments require different humidity levels. These systems offer customization options, allowing users to set humidity targets based on their specific needs, whether it’s a wine cellar, a data center, or a healthcare facility.

Types of Humidity Control Systems For Your Home

Humidity can be controlled in several ways with different types of appliances. An air conditioner will help with temperature regulation and can help to reduce humidity. However, the actual moisture content in that air can be controlled more precisely by other means. Different methods include:

• Using either a humidifier or dehumidifier, with a built-in humidity sensor,
• Using a moisture sensor switch to accurately control the humidity levels, or
• Using a humidistat-controlled extractor fan. This is often the best solution for controlling kitchen and bathroom humidity and where moisture buildup can be severe.

Using Humidifiers Or Dehumidifiers

A humidifier is used to increase the humidity in a home or room. There are several different methods used to achieve this but in a residential setting, the most common involve evaporation or misting element. Either will add moisture to the air raising the level of humidity.

For a look at our picks of some of the best humidifiers on the market, click here.

A dehumidifier does the opposite of a humidifier. When the humidity level is too high a dehumidifier can extract the excess moisture. It does this by collecting condensation on coils that air passes over. The water is then stored in a reservoir to be removed when full or near capacity, or pumped directly into a near drain.

Click here to see more information on our pick of the best dehumidifier at the moment.

For some people that use a humidifier or dehumidifier, these units can do a good job of keeping the humidity levels constant, but they run even when you are not at home (eg. when you are at work). A solution is to install a timer (eg. Hydrofarm TM01715D 7-Day Digital Program Timer), which you can program to turn on a ½ hour before you are due to arrive home. This means that you will not waste excess energy, and the air in your home will be at the right RH level when you get home.

Using A Moisture Sensor Switch

As the name suggests, this unit contains a sensor that monitors the moisture levels in the air. You can then hook this up to a humidifier, dehumidifier, or extractor fan to accurately control humidity or extract moist air.

One problem with using humidifiers and dehumidifiers is that the humidity sensor is built into the unit. As such, they can affect the air in the immediate vicinity and can cause the unit to turn on or off when air further away is not at the correct RH. This can be overcome by using a sensor switch that is separate from the humidifier or dehumidifier.

See more about this option in our review of the WILLHI Air Humidity Controller, and the Leviton Humidity Sensor below.

Using A Humidistat Controlled Extractor Fan

This type of unit combines a sensor and fan into 1 unit. This is a neat solution to automatically switch on when required to control kitchen and bathroom humidity.

Components and Working Mechanism

Automatic humidity control systems are intricate setups that rely on a combination of specialized components working harmoniously to regulate indoor humidity levels. Understanding the key components and their collaborative functionality provides insight into the complexity of these systems.

Components

1. Humidity Sensors: At the heart of automatic humidity control systems are humidity sensors, also known as hygrometers. These sensors continuously measure the moisture content in the air. They can be based on various technologies such as capacitive, resistive, or thermal sensing. The sensor gathers data on the current humidity level and relays this information to the control unit.

2. Control Unit: The control unit serves as the brain of the system. It receives the data from the humidity sensors and compares it to the desired humidity setpoint. This setpoint is typically user-defined based on the specific requirements of the environment. The control unit processes the data and determines whether humidification, dehumidification, or no action is needed.

3. Actuators: Actuators are responsible for implementing the required actions based on the control unit’s decision. There are two primary types of actuators in automatic humidity control systems:

• Humidifiers: When the humidity level is too low, the control unit activates humidifiers. These devices release moisture into the air, raising the humidity to the desired level. Humidifiers can use methods like evaporative, ultrasonic, or steam-based humidification.
• Dehumidifiers: In cases of excess humidity, dehumidifiers come into play. They work to remove moisture from the air, lowering the humidity to the desired level. Dehumidification methods include refrigeration-based, desiccant, or thermoelectric dehumidifiers.

4. Feedback Loop: Automatic humidity control systems operate in a feedback loop. As the humidity sensors continuously monitor the indoor humidity, they transmit real-time data to the control unit. If the measured humidity deviates from the setpoint, the control unit commands the appropriate action through the actuators. Once the desired humidity level is achieved, the system adjusts its actions accordingly, maintaining a dynamic equilibrium.

5. User Interface: Modern automatic humidity control systems often come with a user interface that allows occupants to set the desired humidity level, view real-time humidity readings, and even schedule operation times. This interface provides users with control and visibility into the system’s functionality.

Working Mechanism

1. Data Collection: Humidity sensors detect the current humidity level and transmit this data to the control unit.
2. Comparison and Decision: The control unit compares the measured humidity to the desired setpoint. If a deviation is detected, the control unit determines whether to activate humidification or dehumidification.
3. Action Implementation: Based on the control unit’s decision, the appropriate actuator (humidifier or dehumidifier) is activated to introduce moisture or remove moisture from the air.
4. Continuous Monitoring: Humidity sensors continue to monitor the indoor environment, ensuring that the desired humidity level is maintained.
5. Dynamic Adjustment: As the humidity level approaches the desired setpoint, the control unit adjusts the operation of the actuators to prevent overshooting or undershooting the target humidity.

What Should The Humidity Level Be In My House?

As a guide, the humidity level in your home should fall between 40 and 50%. However, because of fluctuations in temperature, individual rooms, storage spaces, and attics can have different levels. It is actually much easier to explain what your home humidity level should not be.

If the relative humidity falls below 30% it is considered to be too dry. At this level, you may experience skin irritations such as cracked skin, itchy spots, and rashes. It will also dry your respiratory system causing sore throats, coughing and nosebleeds, and even headaches.

When the humidity is above 50% it can create a whole different set of problems; from health issues, to damage to furniture, to promoting bacteria growth. However, it is actually quite easy to monitor and correct the humidity level in your home and in individual rooms and areas.

How Do You Measure Humidity In Your Home?

A variety of tools are available for assessing humidity levels within a room or home. These tools fall into distinct categories: hygrometers, which exclusively measure humidity, and combination devices that offer both thermometer and humidity readings. This range of options allows you to choose the tool that best suits your specific needs for monitoring humidity levels.

Analog-style hygrometers are generally accurate to within 10% (plus or minus) of the actual level. They are sufficient for many applications and will give you a good idea of the approximate amount of moisture content in the air in your home, basement, or crawlspace.

The most accurate measuring device is a digital hygrometer. These are accurate to within about 2.5% plus or minus the actual relative humidity. If you have collectibles or items requiring certain humidity levels, this is no better monitor to choose from.

Installing An Automatic Humidity Control System

You can easily buy an automatic humidity control system and get it installed in your home. Some important things to consider include:

Sensor Location

If the unit contains a remote sensor, it is important to consider the mounting location. As it will be triggering the fan to ventilate the area it is located in, the sensor needs to be away from places that can send false signals to it which will start the fan when it is not required to operate.

Places to keep the sensor away from include doors, windows, heating apparatus, stoves, aquariums, and anything else that could incorrectly trigger the sensor. It should be placed in the center of a wall in order to operate properly.

When you measure the room in which you are installing the system, try to keep the sensor and fan as central as possible. However, the sensor and the fan require distance between them. The fan should be no closer than a few feet from the sensor or it can affect the readings it will receive.

Wireless Sensors

Some sensors available currently are wireless in design. This eliminates the need for plugging them in or running wires between the sensor and fan unit. In this case, the sensor still requires careful handling as well as careful positioning in order to function.

The sensor needs to be able to ‘talk’ to the fan so it can be attached to a wall or sit on a countertop. It can also be mounted to a piece of furniture that does not get moved around (like an entertainment unit). It needs to have a constant ‘connection’ with the fan wherever you place it.

Installation

Depending on the setup you go ahead with, your humidity controller may require professional installation from an expert such as an electrician. They will be able to hook up the new equipment and run wires within the walls if required.

If this is the case, you can still buy the extractor fan, moisture sensor switch, humidifier, or dehumidifier beforehand, and then simply get the professional to do the installation. This way, you have control over exactly what you get and don’t have to pay the markup that the installer may often charge.

Reviews Of Automatic Humidifier Control Systems

See our picks below of some of the best Automatic Humidity Control Systems:

Leviton IPHS5-1LW Humidity Sensor and Fan Control

Designed specifically to address bathroom humidity, this humidity controller system will work well anywhere excess humidity exists. The sensor works with a microprocessor and digital sensing technology which provides constant monitoring and management of room humidity.

It has a built-in timer that will activate the “minimum ON time” of the fan and can be set to run for 10, 20, 30, or 45 minutes. You can also tweak the sensitivity of the sensor with an adjustment option to prevent false triggering of the fan. The sensor can be mounted in a standard wall outlet box.

For more information on the Leviton Humidity Sensor and Fan Control, click the button below, and also have a look a the short video below…

WILLHI WH1436H Air Humidity Controller

This particular moisture sensor switch unit is promoted as being useful for specialized applications including for pets, guitar and instrument storage, and indoor greenhouses. It has a user-friendly design where you can set the levels when you want the fan to switch on and when you want it to switch off.

This product is just the humidity control part of an automatic humidity control system but has many features to enhance that system. What you have to do is connect this to your humidifier or dehumidifier, and then this accurately controls the unit to maintain your desired settings.

All-in-one units can turn off too early because they can change the RH of the surrounding air. The WILLHI Air Humidity Controller provides excellent control of the humidity in the area, as you can provide some separation between the sensor and your humidifier or dehumidifier – something that all-in-one units can’t always provide.

It is fully adjustable and can even switch between humidification or dehumidification modes.

For more information on the WILLHI Air Humidity Controller, click the button below…

Panasonic FV-0511VKS2 WhisperGreen Multi-Flow Bathroom Fan

This could be one of the best bathroom extractor fans with a built-in humidistat humidity controller available.

You could call this an all-in-one package as it includes a premium ceiling fan with a sensor that detects motion and condensation and has an adjustable delay off-timer. There’s no switch required as the fan works as a single unit.

This humidistat-controlled extractor fan turns on automatically when needed and shuts down on its own.

The manufacturer says it is a good design for use in the bathroom, laundry, basement as well as garage but it would do equally well in other rooms (including commercial applications) with high moisture content.

For more information on the Panasonic WhisperGreen Multi-Flow Bathroom Fan, click the button below…

Inkbird IHC200 Humidity Controller

The IHC-200 is an easy-to-use and safe, reliable humidity controller. It features a dual relay output and a play-and-plug design making it a simple solution. There are dual-LED displays, and this product can be used to control both humidifiers and dehumidifiers as well as fans to regulate humidity levels.

It supports calibrating, has alarms for high and low humidity levels, and compressor delaying. Easily switch between humidification and dehumidification with a flick of the mode switch.

This product has many uses including curing chambers, crawl spaces, reptile enclosures, mushroom grow facilities, greenhouses, snake cages, ventilator fans, and more.

AC Infinity Cloudline T8 Humidity Controller

This intelligent controller permits the programming of both temperature and humidity along with the fan speed, timer, and alarm system. It employs a mixed flow system design that is combined with a PWM (Pulse Width Modulation) controlled EC-motor that performs quietly.

The package comes complete with a corded sensor probe, AC power plug, a pair of duct clamps, and all the mounting hardware needed to place this product where you need it the most.

This controller has been designed for use to ventilate hydroponic grow rooms, transfer heating or cooling, cool AV closets, and exhaust odors.

Considerations for Choosing a Humidity Control System

Selecting the right automatic humidity control system is pivotal in ensuring optimal comfort and health within your home. Several factors should be taken into account to match the system with your specific needs:

1. Desired Humidity Range: Different spaces may require distinct humidity levels. Consider the range that best suits your home environment, as some systems might excel at certain ranges while others may struggle to maintain consistent levels.
2. System Capacity: The size of the area you intend to control plays a crucial role. Ensure that the system’s capacity aligns with the square footage of your home to effectively manage humidity throughout all rooms.
3. Compatibility: If you have an existing HVAC system, compatibility is vital. Some automatic humidity control systems can seamlessly integrate with your current setup, enhancing the overall functionality of your home’s environmental controls.
4. Energy Efficiency: Look for systems that prioritize energy efficiency. Opt for systems that activate humidification or dehumidification only when necessary, conserving energy while maintaining optimal humidity levels.
5. Maintenance: Consider the maintenance requirements of the system. Some systems might require more frequent cleaning or filter replacements. Choose a system that aligns with your willingness and ability to perform routine upkeep.
6. User-Friendly Interface: A user-friendly interface makes it easier to set desired humidity levels, adjust settings, and monitor real-time humidity readings. An intuitive interface simplifies the user experience and enhances your control over the indoor environment.

Comparing Different Systems

When evaluating different automatic humidity control systems, it’s crucial to compare them based on their features, capacity, and compatibility. Look for systems that offer:

• Precise Humidity Control: Systems that offer accurate and consistent humidity regulation within your chosen range.
• Adaptive Functionality: Systems with adaptive algorithms that adjust their operation based on external factors like weather changes.
• Integration with HVAC: Systems that seamlessly integrate with your existing heating and cooling infrastructure.
• Smart Technology: Consider systems that offer remote control and monitoring through smartphone apps or other connected devices.
• Humidification and Dehumidification Methods: Depending on your needs, assess whether the system uses methods like evaporative, ultrasonic, refrigeration-based, or desiccant dehumidification.

Real-World Applications

Automatic humidity control systems are commonly found in various industries and environments, ensuring optimal conditions for both people and equipment:

1. Residential Homes: In the home, these systems create comfortable living spaces, prevent mold growth, protect wooden furniture, and enhance indoor air quality.
2. Museums and Galleries: Automatic humidity control is crucial for preserving valuable artifacts, paintings, sculptures, and delicate historical items.
3. Healthcare Facilities: Maintaining proper humidity levels is essential in healthcare settings to prevent the spread of infections and maintain a comfortable environment for patients.
4. Libraries and Archives: Automatic humidity control helps safeguard rare books, manuscripts, and important documents from degradation.

Case Studies: Successful Implementations

• Historical Preservation: A historic mansion successfully implemented an automatic humidity control system to protect antique furniture, paintings, and rare tapestries from the damaging effects of fluctuating humidity levels.
• Data Centers: A large data center improved equipment reliability and reduced the risk of data loss by maintaining a controlled humidity environment through an automatic humidity control system.
• Wine Cellars: A wine cellar utilized an advanced system to ensure the optimal humidity for wine storage, preventing cork deterioration and maintaining the quality of the wines.

Additional Reading & Resources

As you delve into the realm of automatic humidity control systems for your home, it’s essential to have access to reliable sources of information. Here’s a compilation of references and resources that homeowners can turn to for valuable insights and guidance:

1. Energy.gov – Indoor Air Quality Guide: This comprehensive guide by the U.S. Department of Energy offers in-depth information on improving indoor air quality, including humidity control techniques.
2. ASHRAE – American Society of Heating, Refrigerating and Air Conditioning Engineers: ASHRAE provides resources and guidelines on HVAC design and indoor air quality, offering valuable information on humidity control.
3. HVAC School – Understanding and Controlling Humidity: This podcast episode from HVAC School delves into the science behind humidity control, providing insights for homeowners interested in understanding the technical aspects.
4. Energy Star – Humidity Control: Tales From the Damp Side: This PDF looks at case studies, suggestions, and best practices when looking at humidity control and energy efficiency.

Automatic Humidity Control System FAQs

Which Humidity Controller Solution Is Best?

As you can see, there are a number of different solutions, including installing a humidistat-controlled extractor fan, humidity sensor, humidifier, or dehumidifier to remove excess moisture. It will be one of the most important pieces of equipment installed in your home as it can help protect your belongings and your health.

Depending on the specific circumstances, a humidifier or dehumidifier on its own may not be the best choice, but with these options above, you should be able to find an automatic humidity control solution to suit your needs.