Sunday, December 10, 2017

Things that . . . work: EcoSeb DD122EA-CLASSIC Dehumidifier

I have been meaning to do this post for a LONG time, and here it is.  Over the time we have posted about a few items we as full-time liveaboards have found work, and do not work.    Often the differences is in that we USE an item a lot, as opposed to the typical boat which sees maybe two weeks a year of usage – translating into: there is a lot of ‘Marine Grade’ items out there that get glowing reviews and work well, as long as you do not use them.  (those fancy variable speed computer controlled water pumps are a PRIME example).

And here is an item that has proven itself over several winters of constant use:  A full sized desiccant dehumidifier – Specifically the EcoSeb DD122EA-CLASSIC.

During the winter boats collect moisture, and people add to that tremendously through cooking and just breathing.  One of our MOST favorite counter measures is the Dickinson Diesel Stove ( , but conditions do not allow for us to run it all winter.  Instead we kind of cheer when Bad Weather comes to justify its lighting.

The rest of the time we would often had a small cube heater running on low in the aft stateroom.  It occurred to me:  If we are using 400W or so of electricity, why not also try to pull moisture out of the air, not just heat it.  And that lead me to looking into dehumidifiers.  Not the small pellet ones, but proper ones which plug into the wall.   Now most AC dehumidifiers are based on a compressor, much like self contained Air Conditioners.  And in the same light most dehumidifiers are about as noisy as a small self contained Air Conditioner.  But there is a different technology:  self contained re-generating desiccant based units.   These work kind of along the lines of those pellet desiccant dehumidifiers, in that the desiccant attracts and pulls moisture out of the air, but the different is there is a small heater to ‘regenerate’ the desiccant material in a continuous process.  These units do not need to be ‘recharged’ with a bag of pellets, just feed them AC power.

And here is another benefit:  no compressor translates to MUCH less noise!  Really the only noise is the fan circulating air.  On High our unit is a little intrusive if in the same cabin, but we leave it on low often while sleeping in the aft cabin – no issues, just white noise.

Downside of Desiccant vs. Compressor based dehumidifiers?  They are less efficient and use more electricity.  Ours uses from 300w to a bit over 600w depending on its mode.   Well, so what.  We were running a small heater using 400w already.  So the energy usage is the same, we still need the heat, and now we pull over 3-4 gallons of water from the air per day!

This unit has been working well, very well in fact.  I offer we are very very happy with this unit and would recommend it to any one spending the winter on their boat.   Now, if you do not really need that much heat, but only are interested in pulling water from the air, one of the compressor units likely would be a better choice.  But for the PNW  liveaboards, this EcoSub is truly the Cat’s Meow.

There are a few different models available, we have the D122EA-CLASSIC and would get it again.  Smaller in size (about the size of a stand-up oil heater).  Easy to store and works.

More detail here:

And for more of Things that Work (and do not), click here:


  1. What's happening. What about the regular blog posts.. miss your posts. Warren

  2. Will this dehumifer also produce enough heat to warm my boat's interior over the winter? I'm okay with temperatures in the 40s.

    1. Enough? It much depends on how much heat you need. On 'LOW' it produces around 400W, on HIGH it climbs towards 700w. (About the same as one of those small ceramic cube heaters on its lowest setting) For our boat, the 400W is more then enough to heat the aft cabin - but that space is well insulated with few windows. During mild winter (ala, mid 40's outside) it is almost too much heat.

      It is the side effect of heat (we often had one of those cube heaters running on its lowest setting all the time - this unit replaces the cube heater) - combined with the relatively quiet operation allowing it to live in our aft cabin, PLUS pulling moister out that drew us it to.

      (err, quiet is really only on LOW setting the ~400w mode -- any other setting speeds the fab up to a bit too much noise to sleep with).