We often get phone calls whereby people think that their dehumidifier is faulty because it has stopped collecting water. Even when the display shows a low relative humidity below the set point on the dehumidifier they have trouble believing that this humidity is correct especially when it is next to wet washing or in/close to the bathroom.
The fact is that you can have a whole load of wet washing on a clothes horse and that does not mean that the relative humidity in the room is high enough for a dehumidifier to turn on. Initially the water is sitting in the wet clothes and not in the air so at that point the relative humidity in the room has not been effected. Over time the clothes will dry and the moisture from the clothes will increase the about of moisture in the room air but there is no guarantee that this increase in moisture is enough to bring the relative humidity up high enough to turn the dehumidifier on.
To demonstrate this I took a photo of my own dehumidifier that sits outside our shower room door. We have four children and therefore the shower gets used a lots and this photo was taken in the morning after 6 showers had been taken in quick succession before school and work.
Before the showers the dehumidifier reading was 38%rh, after the 6 showers the relative humidity had only made it 43%rh. With the dehumidifier set to 55%rh it is not going to turn on even though it is sat right next to the wet bathroom.
But the bathroom will dry out reasonable well on its own thanks to the fact that the air humidity is dry anyway.
Before taking these photos I had made sure that the sensor was calibrated so that the readings were correct for this demonstration.
The end result has been that that dehumidifier has sat outside the bathroom door and we have not had to empty the bucket for about ten weeks now, this is because the outside relative humidity has been so dry. But during the winter we were emptying the bucket every day, sometimes twice a day.
This is what can happen with dehumidifiers and it is all normal and not something to be too concerned about.
29 Responses
Hi Chris, I have. Meaco ABC & I leave it on all day in my bedroom. I cannot get the reading to go below 58. Any ideas? Many thanks.
This just tells us that the house is still drying out and as the dehumidifier collects water the furniture, walls, clothes, timber, papers are all slowly releasing moisture. Plus of course you put moisture into the air as well through your daily routines. This does not last forever, eventually the organic materials stop releasing moisture and the relative humidity drops further.
Hi Chris
My Zambezi is not shutting off when target humidity is reached. The manual say to clean filter and blow the air sensor with a hairdryer. I can’t find where the air sensor is – would you be able to describe its location?
Regards
George
George,
The dehumidifier should turn off when the relative humidity is 3%rh below your target, so double check whether that is the case. The sensor is behind the air filter and looks like a ‘lego’ block.
Chris
Hello there,
My dehumidifier (Meaco 12L) can for example display 55 on the humidistat and I can do nothing in the house that could increase the humidity e.g. Don’t have a shower, use the washer or dryer, prepare food, open or close doors e.t.c and the number can start rising while the dehumidifier is in operation. I felt that the number should only be going down or staying the same in these circumstances and never going up. Can you explain why this may be happening?
Philip,
Thank you for your purchase and your message. The house itself will release moisture when the relative humidity of the air is lower than the internal relative humidity of organic materials in the house (furniture, wood, paper, clothing, walls etc) and if the temperature in the space drops then the relative humidity will increase as well.
The sensor on the dehumidifier will spot all of these things.
Chris
Hi Chris
When I turn on my meaco dd8l junior set at fan speed 2 and droplets 2 on our boat the dehumidifier does not kick in or any setting accept when I put it to laundry mode then it kicks in I have owned it under a year and filter always cleaned is there something I’m doing wrong.
Regards
Marty
Marty,
If you have tried the three droplet setting and it did not turn on then the relative humidity is below 40%rh which is common for periods across the winter. make sure that it is not positioned in front of a radiator that is turned on as this will lead to the dehumidifier giving a false reading. You can check the humidistat by running the machine in a bathroom, after a bath or a shower. Make the room nice and humid by not running the extractor fan and keeping the window closed. then put the dehumidifier in there on the two droplet setting and let it run with the door pushed to. After 4-5 hours have a look and if you have water then everything is probably of.
Chris
Recently bought the MeacoDry ABC model. When turning on starts at 99 then slowly goes down but never below 68. Also it keeps turning off but the humidty it still above recommended 55 setting. Should the digital display be lit up all the time the dehumidifer is on?
Many thanks for any advice
Toni,
Not sure if you are comparing the reading on the display to another device? But it sounds like you are turning the machine on and off. My advice would be to set it to 50%rh and never turn it off, just let it do it’s thing.
Chris
Dear Chris.
We have just purchased the Meaco 20l low energy dehumidifier. We carried out the instruction of leaving the dehumidifier 4 hours before switching on.
The reading on the device is showing 10%rh higher than 2 separate hygrometers that are both reading the same ‘RH’. Humidifier is showing 66%rh, hygrometers are both showing 55%rh.
We have checked the sensitivity of the hygrometers to see how quickly they adapt to humidity change and both return to original readings within a minute.
It doesn’t matter how long the dehumidifier is on for it is always showing 10% more than the hygrometers.
This 10% will make the difference of leaving the dehumidifier on 24/7 or less frequent use, we have no sign of damp or condensation.
Kind regards
Pat
Pat,
Thank you for your message and your purchase. The most likely answer is that the dehumidifier is correct because the sensor is brand new and will not have suffered from drift yet and most importantly it is benefiting from the airflow from the dehumidifier’s fan. Having a moving airflow will always be a massive advantage.
The other issue could be position because a sensor in another part of a room might be sitting in a different temperature and this will have a massive effect on the local humidity. A 1°C change will result in a 3%rh swing in humidity.
So unless your hygrometers are less than a year old and you paid over £70 each then I would trust the dehumidifier.
Chris
Dear Chris
I recently purchased The Meaco 12L.
I tried it in various rooms around the house and it has made a big difference to the house and the air quality
I live in an old property and the problem comes from the cellar . Some water seaps in from one of the walls when it rains and this causes damp and mould in the cellar. I moved the Meaco to the cellar a few days ago and the reading has come down slightly from 99 to 87 and its full of water when I empty it every day in the evening and early morning. Am I doing the right thing? Do I need different model for the cellar?
Kind regards
Nisha
Nisha,
Cellars often need dehumidification and this can be a long term, all year round battle. Unless it is a very small cellar we would recommend using a Meaco 20L Low Energy dehumidifier down there as they are very good right down to 10°C. This would then allow you to continue to use the 12L dehumidifier in the rest of the house. As there will be no air flow between the house and the cellar you will need two dehumidifiers.
Hope this helps.
Chris
Dear Chris,
Even though the room rh is at 60 with temp at steady 22 C (reading through 2 separate rh wall readers) the Meaco s reading always stays at 99 for an hour or so before the fan starts working. It seems like a long time given the given value is 55. Is it faulty;
Kind Regards,
Alex
Alex,
The high reading when the fan is off is because it is reading it’s internal humidity, so that reading can be ignored. The fan will turn on every 30 minutes to check the room humidity to see whether it needs to start drying the air or whether it should sleep for another 30 minutes.
Hope this helps.
Chris
Hi, we have a 2 month old ABC 12LTR, the unit has been reading far below the 55 that it is set at for the past 4 days (as low as 38), and it has collected no water in that time. Surely it could not naturally consistently be in the 40’s in a small 3 bedroom house with 4 occupants in Surrey in December? It also did this a few weeks ago. In between these episodes it fills the tray of 2.5 litres every 2 days. I am very confused.
Andrew,
We have exactly the same readings here in Surrey too at the moment. We have ours outside the bathroom door and we have 6 in the house. This is normal when the temperature drops outside as we have the heating on for longer in the house and this drives the relative humidity down.
So all good.
Chris
Thanks for taking the time to reply Chris, happy new year to you all
Hi Chris
My meaco always displays 99 rh when first turned on after no less than a day. Is it possible that my flat can be THAT damp? There’s not even condensation on the windows when it says it.. in the first five minutes it comes down rapidly quick to 90 approx. And can get as low as 40 rh in just 3 hours. Is it giving me accurate readings? Mine is second hand but still protected under moneyback scheme if I needed to return it to seller. Hopefully this is not the case!
Thanks
Shannon
Shannon,
All sounds fine, the high reading comes when the fan is turned off and the dehumidifier is just reading it’s internal humidity. Once the fan starts it settles down to the correct room reading.
Hope this helps.
Chris
Hi Chris
I purchased a Meaco DD8L Junior October last night- and on Wednesday night due to the weather I increased the flow rate to bring the Humidity down in the house, however upon doing so it appears that the 30 min cycle is not happening. I have checked the troubleshooting page and performed the necessary clean and reboot but to no avail.
Is there any other procedure that I could try before returning the unit for possible(hopefully not) repair?
Regards
Richard
Richard,
Thank you for your message. You have done the right thing to reduce the relative humidity target on the machine and the dehumidifier will revert to the cycle once the room relative humidity is below the target. So this is not a fault it is just adapting to the new situation.
Chris
How do you calibrate the sensor on your DD8l Zambezi ? Any ideas just wondering where the location of the +/- is
Thanks
Gareth,
It is not possible or readjust the sensor on the dehumidifier. We select sensors that offer a combination of reasonable accuracy and low drift over time so adjustment should not be necessary during the lifetime of the product.
regards
Chris
how about if it shows 99 all the time
If the fan is running then it is a fault. If it is a Meaco and you are in the UK then we will fix it. Just call the office on 01483 234900.