Why does my tumble dryer produce excess moisture

It can be quite concerning to notice that the window of your tumble dryer is covered in condensation, or that there appears to be moisture on the surrounding surfaces of your appliance. But this isn’t necessarily a sign of there being something gravely wrong with your machine. In actual fact, there is often a really simple explanation as to why this happens and it’s definitely possible to prevent this issue from cropping up again without having to call out a repairer.

At Repair Aid, we like to save our clients money, so we’re going to explain why your tumble dryer is producing excessive moisture and detail what you can do to solve this issue – hopefully without spending a penny!

What causes condensation?

Condensation arises from when warm and moist air pushes against either a surface or other air that isn’t as warm. As the warmer air is unable to hold onto that moisture in such conditions, the moisture is passed to the colder surface or air. This causes condensation to happen which is then usually followed by the creation of mould. The number one cause of a tumble dryer producing too much moisture and creating condensation is a lack of ventilation. There are a number of reasons as to why the ventilation could be inadequate.

Diagnosing and solving the problem

It could be something as simple as there not being enough ventilation space surrounding the machine. Just like a laptop that runs warm when it sits on a person’s lap, a tumble dryer will also run warm when it doesn’t have the space to vent the heat. More commonly, ventilation issues arise either from improper placement of the tumble dryer, when the exhaust system has an obstruction, if the exhaust system has been improperly installed or, in some cases, if the vent hose has been hung out the window.

Improper placement

In regards to placement, if your tumble dryer is packed away into a cupboard, then that’s going to be a bit of a problem. With the heat having nowhere to escape to, it becomes trapped in the enclosed space – causing excess moisture and condensation to form. Similarly, if the surrounding environment is too cold – like a garage – then this will also cause condensation to be formed due to the hot and cold air clashing. The first issue can be solved by either moving the tumble dryer to a new location or ensuring that it gets enough ventilation whilst running. This could be something as simple as keeping the cupboard door open. For the latter problem (and even the former problem), the installation of an extractor fan can help capture this warmer air and take it through a vent.

An obstruction in the exhaust system

One problem that will require some further work is when there is an obstruction in the exhaust or if there is a build up of lint in the filter. For the former problem, this can cause a build up of moisture in the duct which can then spill back into the tumble dryer. It’s worth cleaning your exhaust system every couple of years to avoid this problem from happening. Your machine’s user guide or manual will have instructions on how to do this for your model. Alternatively, you can buy a third-party cleaning kit for your exhaust system. For the lint problem, just make sure to empty out the lint screen after each cycle. Lint can not only capture moisture, but can be deposited into the exhaust system – causing an obstruction in the exhaust.

Using the window to ventilate

Another problem that can cause condensation is when the ventilation hose is aimed out of a window. While not as common these days, there are still many homes that don’t have an exhaust system as it can be expensive. The solution to this problem is to run the ventilation hose out of the window. However, this can also cause the condensation to rise back up and through the window. There might be a practical way to manipulate this hose so the hot air doesn’t rise back into the property without having to spend a lot of money on a proper exhaust system.

Installation issues

Lastly, if the tumble dryer wasn’t installed properly, or the incorrect materials were used, this can cause problems. For example, if an exhaust duct is made of plastic, then it can run into more moisture problems than if it was made of metal. Plastics can mix with lint to create even more of an obstruction. This may require the duct to be completely changed to a duct made of metals. If the duct isn’t straight, this can also cause air circulation issues. This often happens if the duct bends and increases the likelihood of a blockage. If the duct can’t be straight, then it needs to be properly supported. Ventilation can also be a problem if the duct is too long as it means that the heat takes too long to exit the exhaust system, causing the temperature to rise and creating the conditions needed to create excess moisture and condensation.

When in doubt, call Repair Aid

If you’ve tried some of the quick fixes – such as re-positioning the dryer, creating more space or cleaning the exhaust system – and it hasn’t worked, get in touch with a repairer to sort out the problem. At Repair Aid, we diagnose and repair tumble dryers on a daily basis and all of our work comes with a 12-month guarantee.