When a dehumidifier doesn't dehumidify

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BelleSerene

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I keep an EcoAir dehumidifier on board: the well-reviewed DD122 (mk4 it says on the back), which came out top in YM's tests.

The last couple of weeks I've noticed that for example the ensign (which I keep down below) was still moist. The EcoAir is purring away, but there's no water down its pipe which I leave into the sink (and I place it on a chopping board above the sink). Today while doing some tasks I took the hose out so any water generated would collect in its transparent container. Nothing.

Mains on, thing pumping air, vent wobbling up and down; just no water.

Anyone cleverer than me have a suggestion? I'd be very grateful.
 
BelleSerene said:
I keep an EcoAir dehumidifier on board: the well-reviewed DD122 (mk4 it says on the back), which came out top in YM's tests.

The last couple of weeks I've noticed that for example the ensign (which I keep down below) was still moist. The EcoAir is purring away, but there's no water down its pipe which I leave into the sink (and I place it on a chopping board above the sink). Today while doing some tasks I took the hose out so any water generated would collect in its transparent container. Nothing.

Mains on, thing pumping air, vent wobbling up and down; just no water.

Anyone cleverer than me have a suggestion? I'd be very grateful.
Click to expand...

Probably too cold for it to work. Compressor types need warmish air to dehumidify, the desiccant types don't. Sorry, don't know the science as to why that is the case.
 
Its been pretty damp here recently and unless you have every air entry point on the boat sealed you will be trying to dehumidify the UK.
 
have you cleaned the air filter at the inlet ?

Take the filter off while the deH is running and touch the pipework. If it is not cold, or there are no beads of mositure, then the gas function is AWOL and needs recharging. But before you do that check for holes/corrosion, etc.
 
I'd guess that DD stands for desiccant dehumidifier, if so, it should grab some moisture from the air down to about 1 degree C, albeit less than at higher temperatures, and there should be no gas issues.

No great ideas, but for a starter, I'd take it home and see how it gets on in a warmer environment, just to check.
 
Easiest solution is to wash your ensign (or give it a good rinse). It will probably have salt on it. That will absorb moisture from the air.

As has been said, if you don't seal all vents, you will never completely dry out the boat.

Usually easier to go the other way - have plenty of vents to create a through draft. Eliminate any leaks and avoid rain ingress. Ensure the inside of the boat and its contents are kept as free as possible of salt (which absorbs moisture) and dirt (which feeds mould). Bob's your uncle. You can retire your de-humidifier.
 
BelleSerene said:
I keep an EcoAir dehumidifier on board: the well-reviewed DD122 (mk4 it says on the back), which came out top in YM's tests.

The last couple of weeks I've noticed that for example the ensign (which I keep down below) was still moist. The EcoAir is purring away, but there's no water down its pipe which I leave into the sink (and I place it on a chopping board above the sink). Today while doing some tasks I took the hose out so any water generated would collect in its transparent container. Nothing.

Mains on, thing pumping air, vent wobbling up and down; just no water.

Anyone cleverer than me have a suggestion? I'd be very grateful.
Click to expand...

Is it pumping out warm or cool air?

If warm then its working - if it's cool / ambient then the heater is broken and ( as with mine ) you need to contact the vendor or Ecoair.


Mine failed after 11 months and was repaired under warranty - hope you are as lucky


Posted from Ybw.com App for Android
 
Starting with the simple - have you ever cleaned the air filter? It'll need a good hoovering if you haven't.
After this, set it to high, wait a few minutes and see if the air expelled is warm - if not the heating element, which is essential to its correct operation, has probably blown.
Little else to go wrong really.
 
Thank you

Thank you all.

So I'll clean the air filter (whoops) and then check the heater. I'm afraid the air output is definitely cold, so that may be broken - or what Sarabande refers to as the 'gas function' (same thing, or to do with a condenser?)

Thanks also for the two suggestions about not bothering. This was my previous position before getting the dehumidifier, but to those who say it can't work in a boat I can only say, try it and you'll feel the difference - and not only in dry bunk sheets. Yes, in theory if she's not hermetically sealed you're trying to 'dehumidify the UK' (hey, if we all did our bit...!) but in reality the air exchange through the washboards is slow and you can literally feel the difference.

Thank you all.
 
BelleSerene said:
... - or what Sarabande refers to as the 'gas function' (same thing, or to do with a condenser?)
Click to expand...

I expect the "gas" referred to is the refrigerant gas, in the type of de-humidifier that incorporates a fridge unit. But it is confusing that the "condenser" of a fridge is condensing the refrigerant by removing the heat from it, as at the back of a fridge where the coils are hot. Whereas in a de-humidifier the "condensate" is the water that has been removed from the ambient air by cooling it below the dew-point.

Although I have heard of dessicant de-humidifiers (and read about them in Wikipedia) I do not know how one can drip the extracted water through a tube. I thought the wet dessicant had to be dried out by heating it to evaporate the water back into vapour, which would be no help in an enclosed space!

Mike.
 
mjcoon said:
I expect the "gas" referred to is the refrigerant gas, in the type of de-humidifier that incorporates a fridge unit. But it is confusing that the "condenser" of a fridge is condensing the refrigerant by removing the heat from it, as at the back of a fridge where the coils are hot. Whereas in a de-humidifier the "condensate" is the water that has been removed from the ambient air by cooling it below the dew-point.

Although I have heard of dessicant de-humidifiers (and read about them in Wikipedia) I do not know how one can drip the extracted water through a tube. I thought the wet dessicant had to be dried out by heating it to evaporate the water back into vapour, which would be no help in an enclosed space!

Mike.
Click to expand...
The DD122 model referred to is an electric desiccant type, lots of them around now, and far, far more efficient at collecting water than compressor types in low temperatures. They can pipe water away.

The DD122 looks absolutely identical to one I bought cheaply from B&Q about 4/5 years ago, though the B&Q one had a different name stuck on - I think it was Airforce. That one lasted about nine months, working beautifully, before having exactly the problem the OP reports - motor whirs but no water extraction. Got a refund from B&Q as they could not replace with another - they were no longer selling them.

I have used dehumidifiers for many years - firstly in Hong Kong where every expat flat had at least one to combat extreme hot damp. A decent compressor type is usually ultra-reliable, but only works well in warm conditions. In cold conditions they are useless, and may freeze up to the point where they damage themselves. The modern electric desiccant types really do work really well in all temperatures but having now had four, seem less reliable. Three of the four I have had developed faults at just under or over a year old - one price refunded, one fixed under warranty, one thrown in skip.
 
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jwilson said:
..........The modern electric desiccant types really do work really well in all temperatures but having now had four, seem less reliable. Three of the four I have had developed faults at just under or over a year old - one price refunded, one fixed under warranty, one thrown in skip.
Click to expand...


Yes, I think a pattern is starting to emerge, see here:

http://www.ybw.com/forums/showthread.php?t=341947

I threw my Prem-I-Air in the skip on Friday.



The 20 year old Matsui is humming away, drying the washing, as we speak. Mind you, it has the same mass as a small traction engine
 
My Prem-I-Air desiccant dehumidifier is still working perfectly after 3 years - you just need to hoover out its air filter regularly (easily forgotten so the heating element tends to overheat and blow).

One last thing - some were fitted with an anti-tip switch, like my fan heater has. It's simply a microswitch that pops out when it is no longer in contact with the floor. They are not always of good quality, and in fact I bypassed mine in the end as it was becoming more of a fire risk than the heater would ever be. The thermostat gives it an element of protection anyway and its never left on unattended.
 
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Thank you all.

The air filter was clean (no credit to me, as I hadn't been checking it) but the air output absolutely cold. I see I bought it in Oct 2010 so it's way beyond warranty, and assuming that repair is expensive I've blown the £150 on a new one new from Ebay.

Thanks again for your thoughts.
 
It really must be infectious! My Meaco DD122 has stopped dehumidifying today and from the previous posts it sounds as if the heater element has failed. It is about 14 months old.
 
Robih said:
Probably too cold for it to work. Compressor types need warmish air to dehumidify, the desiccant types don't. Sorry, don't know the science as to why that is the case.
Click to expand...

The dehumidifier BelleSerene uses is a dessicant unit and should work down to 0degrees C. This unit should also gives out heat as a by product when working. Probably a faulty unit - Suggest you return to seller if still under warranty - I use a Meaco DD8L very satisfied covers the whole boat ok with all doors etc open - trust this assists - good luck ;)

Apologies just read latest above threads
 
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