Can You Use a Heater and Humidifier at the Same Time?

Running a dehumidifier and heater at the same time is okay when there is a need for the same. These two appliances do different things.

The dehumidifier lowers the humidity level in the house. The heater raises the temperature in your indoor space.

Most of the time, we think that we should only run the dehumidifier in the summer. The humidity level can be quite high.

Thus, to bring it down from, say, 70 percent to the range of 30 to 55%, well, it will take a dehumidifier. In winter, you will be running the heater to warm up your living space.

When you might need a dehumidifier in winter

In our article on the humidity and temperature relationship chart, you will remember that we said that warm air holds more moisture.

Warm air is also easier to extract moisture from.

So, what happens when you live in a place like Seattle, which has damp winters? You have cold, damp air outside.

Other places that have cold and wet winters are Oregon and Atlanta. If you live in such places, you can experience miserable winters.

To protect your family, you will need to crank up the heater. Remember, the air is already cold and damp. So, when you turn the heater on, the indoor living space is going to feel too humid.

That is why you might need to use a dehumidifier in the winter. You can remove the guesswork from the picture by using a hygrometer.

As long as your hygrometer shows you the level of humidity to exceed 40% (in winter, we recommend you keep the humidity between 20 and 40%), you need to lower it.

Why you need to lower humidity in winter

We have already seen how warm air has a bigger moisture-holding capacity than cold air. Thus, if your kids are starting to get uncomfortable in the warmth of your house in the winter, check the humidity level.

Dehumidifiers and heating can go together. If you switch off the heating, the air becomes too cold. So, we must agree that you must have heating in the winter.

Image of does a dehumidifier heat a room

Running a dehumidifier and heater also has another benefit. A dehumidifier produces heat. This is why people ask: why does my dehumidifier produce hot air? That is what it is supposed to do.

With the heat emanating from the dehumidifier, you might not need to run the heater for too long.

There is another side to this, though: when you make the air indoors warm, there could be an exaggerated humidity increase. That is why we said you ought to use a hygrometer to find out the level of humidity.

The air can be too dry and warm at the same time. Usually, this is what happens in many homes in winter. If the air feels warm and dry, you need to run a humidifier to increase the moisture content in the air.

Only run the dehumidifier when necessary

Just because you live in a place that has damp winters does not mean that you will always need to run the dehumidifier.

We cannot overemphasize the importance of using a hygrometer to check the humidity level before you can run a humidifier or dehumidifier.

Using technology to measure the level of humidity removes all doubt from your mind. If there is high relative humidity, the hygrometer will show you how high it is! That way, you can know whether to use a dehumidifier or just the heater.

If the air inside is cold and damp at the same time, you can run the dehumidifier and heater at the same time.

Will an electric heater reduce humidity?

If you are running a space heater, you might not find the need to run a heater and dehumidifier at the same time.

Space heaters make the air warmer and drier. However, they do not affect the absolute humidity, but they do lower the relative humidity.

One of the reasons why the space heater seems to lower humidity in your indoor air is that by the time you are running the heater, the air is already too cold. Cold air cannot hold moisture in the same way as warm air.

So, the space heater seems to reduce humidity in the air because there is no humidity to begin with. Cold air has a lower capacity for moisture than warm air.

Even if there is humidity, the heater will still help. Remember, it is also easier to remove moisture from the air when it is warmer than when it is cold.

If you have low humidity, you might want to run the space heater alone and see the effect. If the humidity is higher than 50%, you can run the dehumidifier and the heater. The dehumidifier helps to lower the humidity slightly faster.

How much heat does a dehumidifier produce?

A dehumidifier should produce heat. If it is blowing cold air, it is broken and needs fixing. However, it does not add too much warmth to your room since it can only increase the temperature by 15°F.

You cannot rely on the dehumidifier to raise the temperature in your rooms. In any case, it is going to dry out the air too much. Remember, low humidity has ill effects.

If you use a big dehumidifier in a small room, it will seem to produce too much heat, primarily because of the small space.


It is okay to run a dehumidifier and heater at the same time, when the need arises. The important thing is to check the humidity level with a hygrometer. If your winter humidity level is above 40%, you need to bring it back down.

The heater can help remove humidity. The dehumidifier can help to raise the warmth in the room, if only by a small increase of 15°F. These two appliances—the space heater and dehumidifier—help one another to do their jobs.