Don’t Let Winter Ruin Your Boat – Yachting Monthly

Damp and mold can occur during winter as windows are closed making the surface of walls and windows colder due to the outside air temperature being lower. The moisture becomes trapped within a boat and when it comes into contact with the colder surfaces it starts to condense.

Preventing damp and mold by opening a window to bring in fresh air will work if you are heating the room up, because, by increasing the air temperature, you will decrease the relative humidity of that air.  For example, if you pull air in from outside at 50°F and 80%rh, and then heat it up to 68°F, the relative humidity of that air will fall to around 52%rh. But, when a boat is left empty and unheated for long periods, and contains possessions that are sensitive to changes in moisture, then there is a potential for damage if they absorb and hold the excess moisture in the air. In our example, if air comes into an unheated space at 50°F and 80%rh, then it will stay at 80%rh.  It could well be that the internal temperature is slightly higher than the outside due to insulation but unless it is (in this example) 41°F warmer, the incoming air will not dry below 60%rh. This is the upper end of a ‘safe’ relative humidity zone by conservation experts.

One of the biggest worries for many boat owners is how to prevent such damage in the winter months when conditions are cold and wet. Nothing is worse than returning to a boat after the winter, or even just a few weeks, to be welcomed to a musty smell, an indication of a damp or mold problem.

Every day we have people who call us to say that they are suffering from mold or musty smells over winter. The Meaco DD8L Zambezi will combat these issues and offers more functionality, more control and more options than any other domestic dehumidifier on the market today.

We were very pleased to find our Meaco DD8L Zambezi featured in the December issue of Yachting Monthly.