How Does A Dehumidifier Work

A dehumidifier removes moisture from the air.
A dehumidifier works by drawing warm air currents into its coils with the aid of a fan. Warm air condenses as it moves through the refrigerated coils of the machine. This results in condensation inside the dehumidifier. Water collects in a bucket or drains away.
Cooler, drier air returns back into your home via the other side of the device.
When you have high humidity or dampness in your home, you need a device that is energy efficient. You do not want to have a high electric bill. Let’s look deeper into how a dehumidifier works and how you can make it work for you.
Indoor Humidity
Indoor Humidity

Indoor Humidity

In indoor settings, many factors determine the humidity levels. Indoor thermal conditions and the quality of ventilation are the main contributors. As a child, our basement, had this powerful musty smell that I only figured out years later.
Relative humidity falls by turning up the heating in a room. But this is not a practical choice. Who want to be hot and have a eye-watering electric bill?
Routine activities like cooking, laundry, and bathing lead to excessive moisture levels. Ventilating rooms, by opening windows and doors can bring down the humidity level. [1]

Side effects of indoor humidity

Here are some things that happen when humidity levels stay high for long periods. Above the 60% humidity mark, mold spores and mildew spots begin to grow. High moisture levels will cause rot, property damage, and affect living conditions. You should start thinking about getting a dehumidifier at this stage.

1. Development of mold and growth of mildew.

Microscopic fungi are all around us. Fungi looks like a white or grey film or fuzzy & hairy patches on surfaces like showers and windows. Fungi find the ideal conditions to settle in the damp parts of our homes.
Mold growth appears as black or dark green is patches. Mold can penetrate deep into building materials. Mold can cause health problems like triggering allergies and asthma.
Fungi and mold digest items, like my beloved running shoes. If you do not stop the development of the mold this growth will destroy the objects they resides on.
Growth causes damage to ceilings and walls. In more extreme circumstances, it destroys a buildings’ structural integrity. This may mean throwing away things like soft furnishings, books, carpets, and soft toys.

2. Rotting furniture, boards, and furnishings

Here are some issues you may face when you have excessive moisture in your home. Excess moisture in the home can damage wood.
The high humidity creates stains and can cause severe decay. We had a year where the basement had a burst pipe. We didn’t fix the damp basement.
This had a knock-on effect of making all the furniture damp. The hardwood floors, window frames, and other wooden fittings suffered water damage.

3. Weakened walls and brickwork

Our homes’ walls have air barriers designed to prevent humid, moist air from entering. But vapor barriers are never ideal.
When the weather is warmer, moisture tends to condensate on foundation materials. Condensation on materials in crawl spaces, basements, and garages resulting in structural problems.
As the moisture content in cement, and framing changes, materials expand or contract. This can cause blistering cement, wood, paint, and more.
High humidity can also contribute to cracks, which may lead to expensive repairs cost. As a property owner, it’s no fun spending cash on maintenance. [2]
Benefits2 Images 1

Benefits Of Dehumidifiers

1. NO Mold
A homeowner’s worst nightmare is mold. It kills surfaces by breaking down natural materials. Mold can become toxic if left to spread. Mold puts the health of your entire household at risk. The ideal condition for mold to grow is hot, damp weather, as I have pointed out (50-65% humidity).
A dehumidifier can remove excess moisture, helping to prevent new mold from forming.
2. Improve Air Quality
You measure the air quality by the number of contaminants you inhale and the humidity level in the air. An air purifier is the most efficient way to rid the air of dangerous compounds. A dehumidifier enhances indoor air quality.
3. Reduce Dust Mites
Dehumidifiers reduce high levels of humidity and also remove dust mites. These could be why you have been wheezing so much lately.
Household dust mites are a frequent cause of allergy and asthma related symptoms. In wet, humid climates, dust mites flourish.
Dehumidifiers provide a ideal moisture level, making it hard for dust mites to thrive.
4. Upright Living
High humidity levels will damage the structural integrity of your house. Over time, moisture will weaken the support beams, causing them to split, crack, and warp. Metal fittings will start rusting.
A dehumidifier is an easy way to prevent your home from deteriorating. Provide a safe living atmosphere for your family at the same time. [3]
Types3 Image

Types Of Humidifiers

There are four groups of dehumidifiers.
Water vapor heat pump dehumidifier group
This type consists of a fan, heat pump and hot coils. The fan drives the air past the temperature exchange coils, which are very cold. The humidity present in the air condenses and settles in a tank.
The dehumidifying ventilator group
An ventilating exhaust fan pushes humid inside air outside. This type uses a sensor activated by either a timer or the door closing. You usually find this type in basements, attics, and crawlspaces.
Absorption dehumidifier group
Absorption dehumidifiers are often called desiccant dehumidifiers They are a chemical absorbent type. These devices consist of hydrophilic (water attracting) materials. Chemicals like silica gel remove water from the air. There are single-use and reusable models. Desiccant-type cartridges, gel, and powders are common in most homes.
Home-made group
Those of you who are hands-on can make your own dehumidifier. While I do not suggest it as a permanent solution, it might help in the short term. It is possible to make homemade dehumidifiers out of charcoal, road salt, rice, and more.[4]
When To Install A Dehumidifier
When To Install A Dehumidifier

When To Install A Dehumidifier

It’s time to get a dehumidifier when you have high humidity.
Here are some clear signs of high humidity.
1. You find yourself suffering from allergy symptoms due to damp conditions.
2. Visible water stains on the walls or ceilings.
2. The presence of rooms with inadequate or no ventilation. This is usually in the basements, bathrooms, and rooms with no window.
3. Constant condensation on kitchen, bathroom, or living room windows.
4. You see small black spots (mold spores) growing on the walls. Look in areas with high humidity, such as the bathtub or shower.
5. Must or mildew or funny smells
6. You may also want to consider a dehumidifier if you live where there are lots of other people. Apartment buildings are an example.
Where Can A Dehumidifier Work
Where Can A Dehumidifier Work

Where Can A Dehumidifier Work?

Application of dehumidifier [5] 

The uses for dehumidifiers are wide-ranging and depend on your circumstances. It also depends on environmental conditions, and the building or the room.
A wide range of indications need a dehumidifier:
  • Excessive moisture causes sweating that cannot evaporate. This is due to the number of people in the space.
  • Condensing dripping from cold pipes
  • Furniture and doors warping and sticking.
  • Mold and mildew build up on fabrics, books, and furnishings
  • Infestation of insects. Specific bugs are: moths, fleas, cockroaches, woodlice, millipedes and dust mites.
Home application
Place your dehumidifier in area of your home with moisture saturated air. For instance your: kitchen, laundry room, bathrooms tend to contain the most moisture. Consider a whole-house dehumidifier, as needed.
Office application
This decision depends on many factors, such as room size and the moisture in the areas. Other variables you may consider are room height and airflow. You may need several appliances.
When your space has a low ceiling, you will not be able to wall-mount your dehumidifier. You may need to find a stand for your unit. A stand allows water to drain away.
In the majority of cases, I still suggest floor placement. You can place it under a table. Be sure to place the dehumidifier away from the wall to avoid “choking” the system.
Position the device away from the direct flow of a air conditioner or a heater. Positioning your unit away helps with the airflow. Each dehumidifier has different guidelines for wall proximity. Check the owner’s manual.
How does a dehumidifier work in the basement
A low temperature or basement dehumidifier works at temperatures under 65 degrees. Earth around your basement insulates the area. The surrounding ground is a constant cool 55 degrees.
Standard whole-house dehumidifiers are effective when working at indoor temperatures over 65 degrees. At these lower temperatures, standard whole-home dehumidifiers aren’t good enough.
Bathrooms need a different dehumidifier approach. Small space units are efficient and cut dampness.
How does a whole-house dehumidifier work
Dehumidifiers sizes refer to their capacity. This capacity rating refers to the amount of moisture that the model can withdraw in a single day.
Mini Dehumidifiers have a 1-4 Pint capacity
Small Dehumidifiers range from 5-20 Pint capacity
30 Pint Dehumidifiers have a 21-40 Pint capacity
50 Pint Dehumidifiers range from 41-60 Pint capacity
70 Pint Dehumidifiers have a 61-80 Pint capacity
90 Pint Dehumidifiers range from a 81-110 Pint capacity
Large Dehumidifiers have capacity from 110-160 Pints
Xtra Large Dehumidifiers are larger than 160 Pints
Determine your room’s or home’s square footage. Don’t forget to add the area of your crawl space. Your crawl space is not a “living space” but you’ll need to account for this area.
Next, figure out how much moisture you have in the area.
Less Damp means [50 – 60% humidity] Air SOMETIMES feels damp / musty
Damp means [60 – 70% humidity] Air ALWAYS feels damp / musty
Less Wet means [70 – 80% humidity] Water SOMETIMES on walls / ceilings
Wet means [80 – 100% humidity] Water ALWAYS on walls / ceilings
This Area-Moisture Table indicated the size of appliance you may consider.
Pick the AREA & Pick MOISTURE of your space and find out which DEHUMIDIFIER SIZE is right for you.
What AREA best decsribes your space?

Describe the MOISTURE in your area?
[50 - 60%] Air SOMETIMES feels damp / musty
[60 - 70%] Air ALWAYS feels damp / musty
[70 - 80%] Water SOMETIMES on walls / ceilings
[80 - 100%] Water ALWAYS on walls / ceilings

Workings Of A Dehumidifier
Workings Of A Dehumidifier

The Workings Of A Dehumidifier

The Mechanics of dehumidifiers

Dehumidify or Dehumidification- This means to pull out or remove the water vapor from the air.
It is the process of eliminating atmospheric moisture in various ways. Here are some basic mechanics of dehumidifiers. [6]
Refrigeration Mechanics
This refrigerant dehumidifier uses pretty much the same mechanism as your home refrigerator. Cold metal coils on which moisture from the air condenses cools the air.
A fan draws the room air over to the cold plate. Water droplets form during this process and drip into a water tank or flow into a drain hose. The relative humidity in the room / home goes down to normal levels. Your dehumidifier will then turn to standby.
Refrigerant dehumidifiers are most effective at typical room temperatures. I have noticed that their performance declines when conditions are cooler. This decline in efficiency is because ice crystals form on the metal cooling plates.
I have also noticed that once the temperature falls below 65°F/18°C, there is remarkable inefficiency. After this point, you need a higher-performing unit which tends to push up the price. But low temperature units work well in cooler crawl spaces and basements.
Desiccant Mechanics
Desiccant, or absorption dehumidifiers use a desiccant to absorb water from the air. A desiccant is a material that absorbs water. You’ve likely seen a small pack of crystals labeled “silica gel.” You find them in boxes, with electronics, computers, and other gadgets.
How Does It Work?
A wheel made of desiccant spins through the incoming air stream and absorbs moisture. A part of the wheel passes through a stream of heated air throughout the rotation cycle.
This “reactivates” the desiccant by removing moisture. Condensed water is then collected in the dehumidifier’s collection tank. Otherwise it empties out through a hose.
Desiccant dehumidifiers are often smaller and lighter than refrigerant dehumidifiers. Most desiccant dehumidifiers are portable units.
The advantage of a desiccant dehumidifier is that it can work at lower temperatures. You might want to consider this model if you’re looking for a dehumidifier for a very cool space. , such as a garage or workshop. But, a word of caution.
Choosing the right dehumidifier
Shopping around for the right dehumidifier can seem challenging. Compare dehumidifiers.
Here are a few things to look out for when comparing the different types:
Water removal- here, you are looking at how many pints of water per day can it remove.
A bigger dehumidifier will remove more moisture than a smaller capacity appliance.
Will you be using your appliance in one location or several? Larger units tend to be heavier and more suited to one spot. Portable dehumidifier are appealing as you can move them around with ease.
If you need to run the dehumidifier every day through a wet season, you will need to look for an energy efficient one.
You calculate the electricity costs to run your dehumidifier.
The more power a dehumidifier uses, the harder it is working and the more water it is removing. Bigger dehumidifiers will use more power, and remove more water.
Larger units work faster than smaller ones. Larger units will need to run for fewer hours and smaller ones may need to run all day. It all depends on the area and moisture in that area. [7]
Workings Of A Dehumidifier
Workings Of A Dehumidifier

Maintenance Of Dehumidifiers

  1. Maintaining a dehumidifier is something I learned how to do the hard way. I didn’t see the importance of it and ended up regretting it.
Maintenance is essential if you want your dehumidifier to serve you well for a long time. If you ignore this, it could cost you more in the long run.
Each brand is different. You will need to read the manual before tackling your maintenance. Be sure to get the best performance from your dehumidifier. Here are some maintenance tips.
  • Place your dehumidifier on a level surface. 
  • Place your appliance away from the wall and other obstructions. To ensure good air intake and exhaust, make sure it is at least 6-12 inches away walls and furniture.
  • Make sure to close all doors and windows in the room where your dehumidifier is running. Otherwise, the dehumidifier will run trying to dehumidify outside air.
  • In rooms 65 degrees F and above, dehumidifiers often work best. Get a low temperature dehumidifier built for crawl spaces, basement, and garages.
  • The units air filter eliminates impurities to achieve cleaner, healthier, dehumidified air. If the filter is dirty or not replaced, air struggles to move through the dehumidifier. This makes the dehumidifier work harder. To maintain optimal efficiency, replace your dehumidifier’s air filter on a regular basis.
  • Make sure the internal components are free from dust and soil.
  • Clean the water container often. Emptying your dehumidifier’s water storage tank does not make it a clean water tank. The water tank can become a breeding ground for mold and mildew. 
  • Check the water tank and empty accumulated debris from your dehumidifier. Even if it seems, clean it out with soapy water and make sure it dries before using it again.
  • I hate emptying a water tank. Consider a dehumidifier with a drain hose or pump.
  • Don’t get water on the control panel. Wipe it down as needed with a cloth.
  • Avoid compressor short-cycle Stop flipping the dehumidifier off and on. To turn the dehumidifier back on, wait at least 10 minutes. The elapsed time will allow equalization of the pressure in the system. It will also prevent damage to the compressor.
  • Short-cycling leads to less effective removal of moisture. This is because the appliance does not have time to evaporate excess water. 
  • Look for dehumidifiers with an automatic delayed start feature. This will protect the compressor from short-cycle damage.
  • Inspect the condenser coils for Frost or Ice Build-up. The condenser coils can get icy in cooler temperatures. which can interrupt operation. 

Preventing frost build-up

Do you have ice or frost build-up? Your dehumidifier might be malfunctioning. To access the internal coils, turn the dehumidifier off and unplug it. Inspect the coils.
Find the cause of the malfunction and the take steps to fix the problem. For examples, move the unit away from the wall or move furniture away from the exhaust fan.

Auto defrost dehumidifiers

Consider purchasing a dehumidifier with an automatic defrost feature to avoid this problem. When the device detects ice it shut off the compressor. The fan will continue to operate to melt the frost build-up.
The device resumes once the ice has melted. Clean the grilles of the air intake and exhaust. Dirty grilles can lead to poor performance. Clean the grille that takes in the humid air and the grille that releases the dehumidified air.
You can use a vacuum brush attachment once per season or more. This clears dust and debris blockages and ensures the best service. [8]

Final thoughts

Dehumidifiers may seem complicated, but they are pretty simple. They use a refrigerant or a desiccant workflow. A dehumidifier draws in moisture and traps the water inside. Then, cleaner drier air goes out the other way. Maintenance is straightforward.