Dehumidifier - Keeping the house warm?

richardc1983

I was putting it in terms that people could understand, the everyday person will not understand how the heat pump works its easier to explain that it creates heat, as people wont understand the fact there is still heat in air that is at 2c outside!

Peartree

penrhyn wrote: »

Sounds like a good way of wasting money.
Why not buy a humidity meter and see if you have a problem first?

Not an expert but instinctively think this is the best advice on the thread even though others have got very technical. Even if you have a high level of humidity in the house, would a 'high street' dehumidifier 'dehumidify' an entire house?

I've only come across people using them in modern houses. My parents use one in their modern bungalow where the humidity has been so extreme over this summer that all their doors have swelled. But even so, they can only use theirs on a room by room basis running all the time.

richardc1983

Peartree wrote: »

Not an expert but instinctively think this is the best advice on the thread even though others have got very technical. Even if you have a high level of humidity in the house, would a 'high street' dehumidifier 'dehumidify' an entire house?

I've only come across people using them in modern houses. My parents use one in their modern bungalow where the humidity has been so extreme over this summer that all their doors have swelled. But even so, they can only use theirs on a room by room basis running all the time.

Your best of placing them in the hallway, some are more powerful than others but they pull the moisture out of the house so perhaps they made need 2 if they have a severe humidity problem.

Greenr

Can anyone tell me how to work out how much my dehumidifier costs to run? It's quite old therefore isn't on sale anymore....

economiser

I thought a dehumidifier worked by cooling the air below its dewpoint. This would release the latent heat in the condensed water vapour which would be about 2500kJ/kg (kilojoules per kilogramme) of water. Thus, for example, if you condensed 1 litre of water (1kg) in a 10 hour period you would gain the 2500kJ in 10hours. This translated to a heat flow rate of 2500kJ/10hours x 3200 sec/hour giving roughly 70 watts. Thus the total heating effect would be the electrical input to the dehumidifier plus 70W.

I think there is some confusion by posters relating to the efficiency of heat pumps with dehumidifiers. As both evaporator and condenser are within the same space the coefficient of performance is not relevant. That only compares the amount of heat pumped with the electrical input to the device. The dehumidifier cools the air sensibly at one end and heats it sensibly at the other by the same amount. The only gain , as said above, being the small amount of heat released from the condensed vapour.

Frugaldom

I only just found this thread after starting another one. We have dampness in the house and no heating at all on the ground floor. Would a dehumidifier solve the problem of condensation on windows, mould and doors jamming whilst allowing clothes to dry indoors during wet days? That's basically what I want to know, as running a 300w dehumidifier sounds much better than running a 1000w heater.

Greenr

nykmedia wrote: »

I only just found this thread after starting another one. We have dampness in the house and no heating at all on the ground floor. Would a dehumidifier solve the problem of condensation on windows, mould and doors jamming whilst allowing clothes to dry indoors during wet days? That's basically what I want to know, as running a 300w dehumidifier sounds much better than running a 1000w heater.

Well my dehumidifier definately dries my clothes faster when i'm drying them indoors!! this will be our first winter using it so hopefully (along with keeping windows open more often) it will solve the problem of our mould too!!

Lizzybop

I stumbled across this thread after trying to find out about de-humidifiers.

In our house, once the night temperatures drop (around now) we get dreadful condensation on the windows but only in the 2 bedrooms.

We have double glazing (UPVC you know the type). I have the vents at the top set to open to allow air flow. We have the bedroom door open at night to allow airflow. I make every effort to keep the air fresh around the house. I have windows open at every opportunity. I line dry my clothes outside as much as I can. I have a cooker hood which I use when cooking. I have extractor fans in the bathrooms/loo.

Despite all this, without fail, if the night time temperature gets down to about 6 celsius or below the next morning the windows in our main bedroom and the kids bedroom are wet. The colder it is the worse the problem.

I am at my wits end about this problem. I know that I have now got to spend time every morning between now and march wiping down my bedroom windows.

It doesn't seem to happen to any other house - not that I can see, and I have asked a few friends and some of the other mums from school. It is very visible from outside - it is just SO bad.

Does anyone think a de-humidifier might help - just in the bedrooms maybe??

Failing that any suggestions as to what we aren't doing that we should be, or as to what we are doing that we shouldn't??

Please if anyone can shed any light as to what is possibly going on????? I'm tearing my hair out with this problem - it makes me cry.

Thanks for reading (sorry it's long) please help

optimus_primera

There is set value to how much a particular 'dehumidifier' will cost to run, how much moisture it will pull out of the air etc etc .... it all depends on the climate in which it is situated in.

How it basically works.
Pulls air thur a matrix that 'freezes' the moisture content out of the air, and onto the matrix, it does this for a set period, the it shuts itself down, and the 'ice' thaws and melts and drains into a container.
It then starts 'freezing' again and continues the cycle over again.

Best practice is to do it room by room, ensure all windows and vents are closed, shut the door and leave it.
Putting an electric heater in as well will help draw moisture out of walls etc.
Do not run with windows or vents open (people do) as you will defeat the object of the machine. It will simply try to 'dry out' the external air as well ....
Ignore any claims of how much moisture it can pull, it all depends on what there is in the air.

27col

Frugaldom wrote: »

I only just found this thread after starting another one. We have dampness in the house and no heating at all on the ground floor. Would a dehumidifier solve the problem of condensation on windows, mould and doors jamming whilst allowing clothes to dry indoors during wet days? That's basically what I want to know, as running a 300w dehumidifier sounds much better than running a 1000w heater.

If you believe that you will believe anything. If you input some heat then the condensation problem will largely disappear and a dehumidifier will not be required. Houses that are both heated properly and well insulated rarely suffer from condensation.