Constantly Running Dehumidifiers


By: Evan Scoboria, Last updated: June 28, 2023

It can be puzzling and concerning when your dehumidifier seems to be running non-stop, and the good news is that this is a common issue and often one with straightforward solutions. This article will take you through why your dehumidifier might be running constantly, the implications of this, and how to prevent it from happening.

Understanding Dehumidifiers and They May Run Constantly

What is a Dehumidifier?

A dehumidifier is an appliance designed to remove moisture from the air, effectively reducing the humidity levels in a room or a building. They work by drawing in air, cooling it to condense the moisture, and then reheating it before releasing it into the room.

Common Reasons Why Dehumidifiers Run Constantly

Humidistat Failure

A humidistat is a device that measures the level of humidity in the environment. In a dehumidifier, the humidistat triggers the machine to start or stop based on the humidity level you've set. If the humidistat is broken or malfunctioning, it might not accurately read the room's humidity level. As a result, your dehumidifier may continue to run because it needs to receive the correct information.

Incorrect Sizing

If your dehumidifier is too small for the space intended to dehumidify, it might run constantly as it struggles to reach and maintain the desired humidity level. On the other hand, a dehumidifier that's too large may rapidly lower the humidity, causing it to cycle on and off frequently, which might seem like it's constantly running.

High Humidity Levels

Humidity refers to the amount of water vapor present in the air. The humidity level inside your home can fluctuate for many reasons, and sometimes, it might be higher than what's comfortable or healthy. A dehumidifier can be helpful in such situations, as it maintains a balanced humidity level.

However, if the humidity level in your home or a specific room is exceptionally high, your dehumidifier might run continuously to try and bring it down. This is because the dehumidifier's goal is to maintain the desired humidity level you've set on the device. If the moisture level in the air is constantly high, the unit will keep working to achieve that level.

Many factors can contribute to high indoor humidity levels. Poor ventilation is standard, especially in areas where moisture is regularly produced in kitchens and bathrooms. If the steam from your shower or the vapor from your cooking isn't correctly vented outside, it can increase humidity.

Similarly, many indoor plants can contribute to high humidity levels, as plants release moisture into the air through transpiration. Other factors, such as poor insulation, leaky pipes, or a damp basement, can also increase humidity.

In cases where high humidity is a chronic problem due to structural issues like poor insulation or ventilation, it might be necessary to address those issues to achieve a long-term solution. For temporary high-humidity situations, like a rainy week, running a dehumidifier continuously might be required to maintain comfort and prevent issues like mold growth. However, if your dehumidifier is constantly running even in normal conditions, it could be a sign of a problem with the unit itself.

Dirty Filters

Many dehumidifiers have filters to remove particles from the air before it passes over the cooling coils. If these filters become clogged with dust or other particles, the airflow through the dehumidifier will be restricted. This can reduce the dehumidifier's effectiveness, causing it to run longer to achieve the same results.

Effects of a Dehumidifier Running Constantly

Increased Energy Costs

Like all appliances, dehumidifiers use electricity to operate. The amount of energy a dehumidifier consumes depends on several factors, including its size, efficiency, and how often it's used. If a dehumidifier is running constantly, it can lead to a noticeable increase in your electricity bill.

To understand why, it's essential to know how a dehumidifier works. Inside the device, a fan draws in air from the room. This air passes over cooling coils, condensing the air's moisture into the water, then collected in a tank. The dry air is then reheated and expelled back into the room. This process requires energy, and when the unit runs continuously, it consumes electricity non-stop.

Energy Star-rated dehumidifiers are designed to be more energy-efficient than standard models, but even these will use more electricity the more they operate. Some dehumidifiers also have features like automatic shut-off when the desired humidity level is reached or when the water tank is full, which can help save energy. However, if your dehumidifier is constantly running despite these features, it could be a sign that the unit is working harder than necessary to dehumidify your space, which can lead to higher energy costs.

In addition to the direct cost of increased electricity usage, there's also the potential indirect cost to consider. A constantly running dehumidifier can add heat to a room, which might make your air conditioning system work harder to keep your home cool, particularly in warmer months. This can further increase your energy costs.

Wear and Tear of the Unit

Like any other mechanical device, a dehumidifier is subject to wear and tear over time, especially if running constantly. The continuous operation of the unit places stress on its various components, potentially leading to faster degradation and the need for more frequent repairs or even a complete replacement earlier than expected.

Here's a closer look at how constant operation can contribute to wear and tear on a dehumidifier:

1. Motor fatigue: The motor is one of the most critical components of a dehumidifier. It powers the fan that draws air into the unit and over the cooling coils. If the motor runs continuously, it's more likely to experience fatigue and fail. Motor replacements can be expensive; in some cases, replacing the entire unit might be more cost-effective.

2. Strain on the compressor: The compressor is another vital part of a dehumidifier, and it's responsible for circulating the refrigerant that cools the coils and condenses moisture from the air. The constant operation can strain the compressor significantly, potentially leading to failure over time.

3. Cooling coil wear: The cooling coils, where the air is cooled to condense moisture, can also degrade faster if the dehumidifier is constantly running. Over time, the coils may develop leaks, affecting the dehumidifier's performance and potentially causing other problems, such as refrigerant leaks.

4. Filter clogging: Dehumidifiers typically have filters to clean the air before it's drawn over the cooling coils. If the unit is constantly running, these filters can become clogged more quickly, which can restrict airflow and cause the unit to work harder, contributing to more rapid wear and tear.

In short, while dehumidifiers are designed to run for extended periods, running them constantly can accelerate the wear and tear on their various components, potentially leading to more frequent breakdowns and a shorter overall lifespan. Regular maintenance, such as cleaning or replacing filters, can help prolong the unit's life. Still, if your dehumidifier runs non-stop, it's worth investigating why to avoid unnecessary wear and tear.

Increased Noise Pollution

Noise pollution is often overlooked, but it can significantly impact your comfort and quality of life, especially in indoor environments where a dehumidifier might be running constantly. Although dehumidifiers are not typically excessively loud, they do generate a continuous background noise that can become bothersome over time.

Here are a few ways in which a constantly running dehumidifier can contribute to increased noise pollution:

1. Continuous operation: Most dehumidifiers produce a low hum or whirring noise when they're in operation. While this might not be a problem for short periods, when the unit runs continuously, this noise can become more noticeable and potentially disruptive, especially in quieter environments or during periods when you prefer silence, such as at night.

2. Vibrations: A constantly running dehumidifier may vibrate over time, leading to additional noise. This can occur as components wear down or become loose due to the constant operation of the unit.

3. Wear and tear noise: As discussed earlier, a constantly running dehumidifier can experience accelerated wear and tear. This can lead to various types of noise, from rattling sounds caused by loose parts to high-pitched whines from a failing motor or compressor. These noises can be disruptive and indicate that your dehumidifier needs maintenance or repair.

4. Increased fan speed: Some dehumidifiers adjust their fan speed based on humidity. If the humidity level is very high, the unit may run at a higher fan speed, which can be noisier.

It's important to note that not all dehumidifiers produce the same amount of noise, and some models are designed to be quieter than others, so if noise concerns you, it's worth looking for a model known for its quiet operation. However, even the quietest dehumidifier can contribute to noise pollution if it's constantly running. Addressing the constant operation's root cause can help reduce noise pollution and other potential issues, such as increased energy costs and wear and tear.

Tips to Prevent a Dehumidifier from Running Constantly

While a dehumidifier can significantly improve your home environment's comfort and healthfulness, running constantly is not ideal. Here are some practical tips to prevent your dehumidifier from running non-stop:

  1. Proper Sizing: Before purchasing a dehumidifier, it's essential to correctly assess the size of the space where it will be used and the humidity level in that area. Dehumidifiers come in different sizes and capacities, each suitable for specific conditions. A unit that's too small will struggle to reduce humidity levels effectively and may constantly run, while an overly large unit can lead to unnecessary energy use.
  2. Regular Maintenance and Cleaning: A dehumidifier requires regular maintenance to function effectively and efficiently. This includes cleaning or replacing filters as the manufacturer recommends, checking for and fixing any leaks, and cleaning the water tank, air intake, and exhaust grills. A well-maintained dehumidifier will run more efficiently and be less likely to operate constantly.
  3. Proper Placement: Where you place your dehumidifier can significantly impact its performance. Place the unit away from walls and furniture for best results to allow for adequate air circulation. If high humidity is localized in specific areas, such as a basement, ensure the dehumidifier is placed there.
  4. Humidity Level Monitoring: Regularly monitor the humidity levels in your home using a hygrometer, an instrument that measures the humidity in the air. The Environmental Protection Agency (EPA) recommends maintaining 30-50% indoor humidity. If the humidity level is within this range, there's no need for the dehumidifier to run continuously.
  5. Use of Humidistat: A humidistat is a device that measures and controls the humidity in the air. Many dehumidifiers come with a built-in humidistat, which allows you to set your desired humidity level. Once this level is reached, the dehumidifier will automatically shut off, preventing it from running constantly. Consider investing in a standalone one if your dehumidifier doesn't have a built-in humidistat.
  6. Optimize Your Home's Humidity: Many other ways to manage humidity can reduce the burden on your dehumidifier. This could include improving ventilation, especially in areas like the kitchen and bathroom, repairing leaks or damp spots, and using moisture-absorbing products in particularly humid spaces.

These tips can help ensure your dehumidifier operates efficiently and effectively without running constantly. This will help maintain a more comfortable and healthier living environment.

Finding a Balance: When to Run and When to Turn Off

Striking the right balance for when to run your dehumidifier and when to turn it off is critical to its efficient operation and longevity, not to mention your comfort and energy costs. Here are some points to consider:

  1. Monitoring Humidity Levels: The first step in determining when to run your dehumidifier is to know the current humidity levels in your home. The ideal relative humidity level is between 30% and 50%. If the humidity level in your space is consistently above this range, then running your dehumidifier is beneficial. You can turn off the unit once the desired humidity level is reached. A hygrometer, a tool that measures humidity, can help you accurately track these levels.
  2. Considering the Weather: Weather conditions greatly influence indoor humidity levels. You may need to run your dehumidifier more frequently during hot, humid weather. Conversely, in cooler, drier weather, you may find that your dehumidifier can work less hard. Please always consider the weather when deciding on your dehumidifier usage.
  3. Proper Sizing and Placement: A dehumidifier that's the right size for your space and placed in the optimal location will work more efficiently. If the dehumidifier is too small for the area, it may run constantly without significantly reducing humidity levels. Conversely, a too-large dehumidifier may cycle on and off too frequently, which can wear out the compressor.
  4. Use of a Humidistat: A humidistat can be an invaluable tool for maintaining the balance of when to run your dehumidifier. Many dehumidifiers come with a built-in humidistat that you can set to your preferred humidity level. The dehumidifier will then automatically turn on when the humidity level exceeds your set point and turn off once it's achieved.
  5. Nighttime Use: Depending on your specific conditions and needs, you can run your dehumidifier at night. This can benefit energy consumption, as some power companies charge less for electricity during off-peak hours. However, keep in mind that dehumidifiers can produce noise, which may disrupt your sleep.

Remember, achieving a balance doesn't mean you must have your dehumidifier running constantly. It's about understanding your environment, the capabilities of your unit, and your comfort needs, then adjusting accordingly.

Closing Thoughts

A constantly running dehumidifier can be a symptom of various issues, from faulty parts to incorrect sizing. Understanding these potential causes helps you troubleshoot and solve the problem. Remember, while a dehumidifier can significantly improve your living environment, it's essential to find a balance to avoid the downsides of constant use, such as increased energy costs and faster wear and tear. Regular maintenance, monitoring your home's humidity levels, and adjusting your usage according to the weather can go a long way in maintaining an optimal humidity level in your home while ensuring the longevity of your dehumidifier.