Does a dehumidifier heat a room? What to know if you're looking to lower your heating costs

MeacoDry Arete® One 20L Dehumidifier/Air Purifier
(Image credit: Meaco)

‘Does a dehumidifier heat a room’ is becoming a very common question as we look to find cheaper ways of heating our homes, and this question has a very simple answer: yes, it does, but only some very specific models.

Dehumidifiers are a surprisingly versatile appliance. As well as removing humidity and damp, they can be useful if you’re looking at how to stop condensation in your home as outdoor temperatures start to drop. But how effective are they as heaters?

Dehumidifiers naturally create a small amount of heat as they operate, and depending on the size of your room and how often you run your dehumidifier, you might experience a few degrees increase. 

It’s best to consider this heat as an effective source of background heating, rather than a primary heating source, but in certain situations you might be able to reduce the amount of heat required from other forms of heating, therefore lowering your heating costs.

How do dehumidifiers heat a room?

A dehumidifier naturally heats and cools air as it removes moisture, pulling moisture from the air then returning dried hot air which circulates through your room. This warming process is particularly noticeable in damp rooms with higher humidity, which will feel colder to be in.

But while dehumidifiers can make most rooms feel a little warmer, the differences between the two types of dehumidifiers are important to consider if you’re looking for more heating for your buck and to justify your dehumidifier’s running costs. 

A desiccant dehumidifier is the optimal choice for increasing your room temperature because it has an in-built heating element, which ensures that warm air is passed back out at a higher temperature than the air that is taken in. 

A compressor, meanwhile, features a rotary design that will still make a room more comfortable and less humid, but ultimately will not noticeably warm the air. 

When is a dehumidifier better than a heater?

You might think that a space heater is the clear, obvious choice when it comes to warming a room, but this is not always the case.

In particularly humid rooms - where it will feel colder than expected - a desiccant dehumidifier can be better value because it removes moisture as well as heating the air. A heater will warm you up, but it will not address the problems behind colder rooms. This can also be the case for older houses with poor insulation, where cold walls and windows can increase the risk of damp. 

However, in rooms that are generally well-insulated or larger spaces that require more heat, a space heater may be a better option. And in very cold periods, it is unlikely that a dehumidifier alone will be able to sufficiently warm larger spaces. 

Jack Woodfield
News Editor

Jack has worked in journalism for 11 years and is the News Editor for Homebuilding & Renovating, a role he has had since 2019. He strives to break the most relevant and beneficial stories for self builders, extenders and renovators, including the latest news on the construction materials shortage and hydrogen heating. In 2021 he appeared on BBC's The World at One to discuss the government's planning reforms. 


He enjoys testing new tools and gadgets, and having bought his first home in 2013, he has renovated every room and recently finished a garden renovation.