What is correct for my room? How do I select the right one for my requirements?
This is one of the most commonly asked questions, but unfortunately, it is not very easy to answer.
Manufacturers will usually give an idea on the box of what sized room the unit is designed for. Useful though this is, humidity levels in a room can vary tremendously, so real life is not that straightforward.
A better question to ask is, "how much moisture do you need to remove?"
Sometimes, you will see claims on the box or advertising materials about how many liters of water can be removed from the air in a day. This is another useful guideline, but it is partly dependent on the temperature of the air and how humid it is to start with.
These guidelines do provide is an easy way to compare the dehumidifiers with each other. By looking at a selection, you can quickly see which are most powerful. All you have to do is decide how much power is required, then you are ready to go shopping!
If you have a consistent source of damp in a room, then you will have a continuous battle on your hands, and should buy the most powerful dehumidifier you can find. This could be a leaky roof or floor, bad plumbing, or perhaps a clothes dryer and that is regularly used. On the other hand, if there is little to do, you could probably get away with a unit designed for a much smaller space.
How important is it to choose the most appropriate model? To be honest, it's not that important at all. An over-powerful unit with variable speed control and a built in humidistat will be able to cope with almost any situation. You simply switch to a suitable speed, and let the built in humidity control do the rest. If cost is an important factor, you may be more tempted to buy an under-powered unit. Again, this would not be a problem. If it turns out not to be sufficient for the task, you can always buy another at a later date and use them together.