New Dehumidifier

tomframe

Well-Known Member
Joined
17 Aug 2005
Messages
148
Visit site
With winter here, I am off to buy a Dehumidifier, I have seen all the posts about the B&Q ones and they sound great value for money, what about this one. some interesting sales blurb below, but is it all pie in the sky?

http://www.breathingspace.co.uk/pages/amberdry.php

Traditional dehumidifiers rely upon the ambient room temperature being fairly high to help with the dehumidifying process. In short, the warmer the room temperature the more moisture they will collect. Likewise the colder the room temperature, the less moisture they will collect. This is not ideal because in the winter ( when we are most in need of a dehumidifier) the temperatures get very low. In fact, when the room temperature falls below 15deg C , the extraction rate drops significantly.

So, before you purchase any dehumidfier, ask yourself the 5 key questions:

Question 1. What is the temperature in the area to be dried?
If temperature drops below 20deg C, an absorption dehumidifier is your best choice.

Question 2. Do you want to get the utmost out of the electricity you use?
An absorption dehumidifier not only dries but also warms your room. It is the best choice for effectively using electricity.

Question 3. Do you want a quieter dehumidifier?
An absorption dehumidifier operates at only 29 dBA. It is the best choice for peace and quiet.

Question 4. Do you want a light and portable dehumidifier?
Weighing in at only 7Kgs, and with an integral carry handle the Amber dry absorption dehumidifier is the lighter choice.

Question 5. Do you want to help reduce environmental impact?
Free from all 'greenhouse' gases , Amber dry is the responsible choice if you care about the environment.
 
Nice to hear the sales pitch, BUT

HOW do you get rid of the moisture from the silica gel ? At some point it will reach saturation, and then has to be dried out before being re-used. This needs energy, lots of it, so the recommendation is to use SG for closed spaces such as small closed cupboards and chests. Large open spaces will need a dehumidifier which dumps the extracted water into a tank, which can be emptied at intervals. The water won't evaporate from most of the tank designs I've looked at.

Probably a nice device for home but not for the marine environment ?
 
Yes interesting and sure it works, but myB@Q dehumidifier placed in my boat at the beginning of last winter kept it dry from any damp and worked so well (placed on the heads sink), it will be used again this winter, the results of using one were far better than I could have imagined. Just a view.
 
I believe these units use heat to dry the silica wheel -producing the condensate -hence the power consumption I think.Unless someone knows better!Used not to be very viable on small units so the one shown is interesting. Conventional ones are much better now at lower temps than they used to be ,but its worth checking at what low temp they cut out -or indeed if the cheap ones do automatically stop?Otherwise just wasting electricity
 
I have one of this type as well as a std. B&Q style. I have not measured the quantity of water each extracts( both on autodrain as I visit the yacht every 3 weeks), but inclined to believe that at low temps. the B&Q model is more of a fan than dehumidifier.
Only disadvantage I can see is Silica model does not autstart if yard power tripped.
 
The test PBO ran on silica gel wheel units concluded that at winter temperatures they were 3 to 4 times more effective than compressor types. Therefore you could put one on a timer to run for 2 hours twice a day and get the same results as leaving a compressor type running all the time. The end result was a big saving in electricity.
 
Homebase have a similar unit to the B&Q one for a slightly cheaper £63.. I bought one today as couldn't find one of the new fangled versions with a continuous drain
 
Imagine a disc of silica that rotates, much like a disco lighting oil-wheel. At any time about a third of the disc is in the path of the room air circulating fan and a third is being heated. The disc is rotating and it is a continuous process. Water is absorbed when the disc is in the path of the room air and dried later, on its way round, by the heater. The hot, humid air is cooled by a simple heat exchanger (bit of steel plate) and the water drains away. There is no more of a problem with being in a marine environment than with any other dehumidifier. Also, remember that if a boat has a dehumidifier running the air is nice and dry - no rusting, smells or mildew /forums/images/graemlins/smile.gif I'd never keep (or live aboard) a boat in the UK without a dehumidifier. We had two living aboard in Chichester.
 
Yes I Bought the Amberdry from B&Q 2 years ago.

It is very good, in my opinion worth the extra outlay.

Used for 2 winter seasons I can report that it uses no more electricity than a standard compressor type but with the added advantage of warming the cabin.

The extraction rate is as claimed & it also provides some air circulation.

Will be putting it back onboard this winter.

Had to leave the soft furnishings aboard last winter & they were bone dry throughout.

Two points though before you make your choice.
If the power fails the unit shuts down.....................so idealy you need to check it's running weekly & you need to check the carbon filter monthly as instructed in the user manual.

These asside it is an excellent unit.

We leave a month between vissits & it's always bone dry & warm on our return.
 
I am looking for a dehumidifier and considering the AmberDry, but not sure if it could be run from a time-switch, and not convinced yet on cost/benefit

Re running costs: 6 months is 3624 hours, and with the Amberdry consuming 435W this gives 1577kWh. I pay 5.8p/kWh so cost for the period is £91.44. A 220W compressor type would be anout £47.

So, the running cost difference is about double. Does the performance justify this, especially given the high capital cost?
 
There are two separate issues here. If it is correct that this machine will not re-start after supply restoration then timeswitch operation is impossible and it will have to run continuously. That does not necessarily mean at full load all the time. The literature quotes a sound level which varies which I would take to mean that something else - fan speed as a minimum - must also vary. It also talks about automatic operation, and indeed three buttons are displayed with different %age RHs. I would assume that automatic operation would mean stopping dehumidification when RH is at or below the pre-set level, and I would imagine that to achieve this the heater is switched off, but the literature doesn't make that clear. (If some other mechanism is used and the heater keeps running then much of what follows is incorrect.) Assuming, however, the above is correct then, providing that sources of new moisture are limited, I would expect an energy usage considerably less than rating X operating hours.

The second issue is the comparison of technologies. If the quoted performance graph is correct, then at low temperatures a compressor type having equivalent output at normal room temperature will have to run for much longer periods (higher duty cucle) than the dessicant type to extract the same quantity of water, which should mean a lower running cost with the latter. Again, though, the key issue is how much new moisture is being introduced since, after initially reducing the RH to the desired level, this will in the main determine the duty cycle.

FWIW for the winter I currently use a compressor type controlled by a humidistat and, while I don't have figures to hand, It doesn't run up a huge bill - and I'm charged over 10p / kWh. It's a pig of a thing to hoist on board though. I've just weighed it: 16.7 kg - that's more than my anchor! So I can definitely see one advantage of a 7 kg device. I acquired (from the skip!) a tubular heater, and have been meaning to also use that, controlled by a thermostat set somewhere between 5 and 10 degC, but that's still on the "to do" list, but would not be necessary if I used one of these dessicant machines. I haven't decided, but am thinking. If the existing unit packed up this would probably be my replacement route.
 
You are assuming that the Amberdry is running at full power for the entire duration, this of course is not how it works in reality.

At startup it does run on full power untill it reaches the desired RH (relative humidity) which you can preselect (20,40 or 60%), it then maintains this by only opperating when required, a bit like climate control in a car, you set it & the unit maintains the RH of the area in which it's been placed.

Granted on full power the figure for consumption is worrying but in reality it is no where near double the compressor type.
Dont forget that it is humidity controled & more efficient so it runs less often.

It cannot be used with a timer due to the nonmechanical on/off switch therefore if power is lost the unit shuts down but it regulates itself on & off when required so there is realy no need for it to be timed.

I have no specific interest other than a satisfied user & as posted previously I bought it for £100 in a mix up over sale price at B&Q.
If however it had been the £200+ that I see it for sale at then yes I probably would have bought the compresser model next to it but having used an amberdry I would buy it again. /forums/images/graemlins/smirk.gif
 
Hmm. Overtaken by technology advance; I thought it was a batch type process - apologies for the nasturtiums. Must investigate.
 
Top