Dehumidifier drainage

[dunedin]

To have an objective view of the potential alternative methods you need one or more temperature & humidity sensors, with max / min function. Readily available for less than a tenner.
We have one which we have on board and check every time we return to the boat (generally every 2-3 weeks in winter). Without this it is just opinion.
Even when sailing in August, in Scotland on wet days the basic air humidity was often over 85%, occasionally 90%. So ventilation with air that damp won’t help a lot. Even when we leave the boat on a warm sunny day with humidity around 40%, this doesn’t last when left for a few weeks with natural ventilation. Will often find a peak of near 80% on return.
Hence we use dehumidifier on minimum from late October onwards and tube heaters on temperature sensor from December (the suggestion of few days below zero in the Clyde area is a big generalisation - had brief periods of air -10C or more on bad winters, a problem if ashore without winterising but generally not afloat in salt water.

 

[Momac]

Given the amount of rain falling the last few days I may have to take the dehumidifier to the boat sooner rather than later .
That is if I can actually get to the boat as the car park may be flooded and there is no way I am going to wade through water to get to the pontoon.

 

[ashtead]

Drain by sink with outlet open -I guess you are in marina so be sure to keep your electricity topped up if you have a prepay account as even on low setting it seems running costs higher than expected -obviously that depends on your marina though but we leave ours on all winter and I have heard that liveabords use them as a gentle heater if yours has this function. Ours is a Meaco I think . We do also use crystal tyres in cabins from around Dec.

 

[Oddduck]

Hi,

As a background: Since putting a seago ecodry on the boat yesterday afternoon I’ve got the relative humidity down from 70% to 46%. It’s producing a lot of water. Overnight just maintaining that % it filled its water tank.

The choice:
A) I don’t use it when I’m not here (I don’t think this is an option)
B) I drain it to the bilge and let the bilge pump take care of it
C) I leave the galley sinks seacock open and let it drain that way

Both B&C have drawbacks. E.g my bilge pump would have 2-3 extra cycles a day.

Second choice, what relative humidity do I aim for. The debice will turn off and on based on this.

Any best practice advice greatly appreciated.

If the boat is kept well closed up(ventilation or dehumidification, pick one, not both as many seem to). It will taper off quickly. Also, heating the boat helps at first.
My sequence if I cannot find a sink or other appropriate drain, and don't want to bother using a small plastic tub on the bilge to relocate the bilge pump into.
1. Scrub down/wash all the hard surfaces, open lockers and prop up cushions.
2. Set dehumidifier to the lowest humidity.
3. Set a heater on at least medium.
4. Run this at least 48 hours draining as often as needed.

After this, I set it to 65% and turn the heat on to a level that will only trigger of freezing is likely.
Because I've stripped the moisture out, I typically only need to dump every 14 days. This is less effective if your boat leaks of course.

Simpler options: short hose to a sink and leave the drain open. Or a shower if you've a automatic pump on it.