Dehumidifier novice, I have questions!

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I have just bought a dehumidifier, never used one before. My last house had a warm air current running through where the washing hung to dry and we never saw anything of concern, but I have moved so thought I should err on the side of caution rather than create a load of damp/mould. This house feels much more sealed than my old place.

My questions are:
-can I assume that I have no damp problem if I only have very minimal condensation?
-if you use a dehumidifier is the aim to never open windows? Or do you use the dehumidifier in combination with ventilation at other times?
-do people monitor how damp their houses are or go on visuals?

I am not sure if a dehumidifier for the whole house will suit me as I am old school and used to just opening all windows - the washing is in an enclosed space so that is where I am using the machine for now.

Watching with interest … we’ve just had one delivered this week. And I don’t really know what I’m doing with it. 🙈 At the moment I’m leaving it on for 2 hours upstairs and 2 hours downstairs and there’s a fair bit of water being collected. I don’t know if I should leave the windows open or not. It seems more damp outside than it is in at the moment!

Watching too. It suddenly feels like we should have a dehumidifier. In summer the windows are open all the window but this winter I’m being for cautious.

I’m also worried about leaving it on when I’m out… but if I don’t then it’s never going to be on long enough to make a proper difference. (Fire hazard worries etc, although it’s a good one, £200 ish and has auto shut off etc). At the moment I’m waiting for my car to be serviced and left the dehumidifier on at home upstairs and I’m sitting here worried my house will burn down. Which is over dramatic I’m sure as the fridge freezer is always on as is the modem etc 😳😆

I just run mine next to my washing drying on the stand. That's it. Turn it on and off depending.

Air can get really dry so then I leave it off a while.

I'm impressed by how quickly my washing seems to be drying with it on, and the room doesn't seem damp at all. I am worried about the cost of running it!

If you have minimal condensation you don’t have a worrisome damp issue. Still good practice to wipe the windows in the morning though to protect the window frame (whether UVPC or wood).

With the dehumidifier, you definitely want to close the windows unless you plan to dehumidify the world :) Best result for drying laundry is in a small room, door and windows closed, and a fan running if possible.

We have small electronic damp and temperature sensors throughout the house. My husband loves data but it’s genuinely quite useful.

We have had one for years and has really helped with condensation and damp smell. We have it on 24 hours a day from about Oct to April when it is cold. If we open the windows we turn it off. We have it next to drying washing if needed if not we move it round the rooms down stairs. If it's not needed then my eyes get itchy if you see what I mean !

I understand the windows should be shut when running the unit, but can/should I run my dehumidifier in the day, then do what I normally would overnight and set up a draught - or am I letting in more wet from the outside for teh machine to deal with tomorrow?

I am finding it weird to seal up my house, I am accustomed to a draught.

I'm going to get a hyrgrometer I think.

I would think it's not going to cause damp if you open the rondo at night and turn off the dehumidifier. Condensation at night would be caused by everyone breathing in a house with closed windows. It's good to get fresh air through the house. But I think it's good to have the dehumidifier generally reducing condensation and damp - when it's really cold you won't want the windows open.

@Porridgeislife what kind of sensor do you have for damp? That sounds really useful.

Really good video here about mould and condensation

I'd still recommend opening the windows for fresh air.

Put your wet washing on the airer and sit the machine next to it. Put it on laundry setting and let it run. I have run mine overnight or whilst out for the day many many times. No issues.

PS.
Yes it costs to run but it creates heat as a by product of it working so it warms up the room so you can use the central heating less.

We have an old house and it's not fantastically insulated, we don't have any major issues with damp but it is something we need to keep on top of in our bedroom and the back bedroom during the colder months.

We have one dehumidifier which we use in our bedroom that we share with baby DS. Ours you can set it to a certain level of damp-ness (roughly), we also have little sensor things that were fairly cheap off Amazon that are room thermometers and also measure humidity. We use that as a guide, but generally we have it set to fairly high all day long (it switches itself off when it reaches the required humidity in the room so it's not actually on all day!). Then we have it set just under half way on the quiet nighttime setting from when DS goes to bed until he wakes up in the morning. Then crank it back up more when we get up to a higher setting and the louder daytime one. Windows and door closed when it's on or it won't work efficiently. It's cheap to run compared to central heating or whatever and it does make a noticeable difference. We didn't use it the first winter or two we lived here and we got a lot of damp near the windows and it was time consuming to clean it up but it's much less when we uze the dehumidifier a lot thankfully. Saves us a lot of time cleaning and better for our (and now DS's) health too.

The rest of the house we don't have any visible problems with mould so don't see the need to use one. Except for back bedroom but that's unoccupied so we don't bother and just do regular deep cleans of the mould as needed really. We are planning to move DD into that room sometime soon-ish though so we might buy another dehumidifier for it when that happens though. However we will then heat the room more too and some of the furniture will be reconfigured so the walls can breathe a bit easier too, so that should all help improve the problem too.

Placemarking

Thanks all for input. My plan then is use the dehumidifier in the day for washing and a bit upstairs (where the condensation is sligthly worse, if there is any) but overnight revert to my old ways of airing the house.