Dehumidifiers - stupid question....

[SequinBear]

I bought a small one (only 1.5l) out of an urgent need after a day of unseasonably humid and foggy weather in the autumn, which caused it to basically rain down all my inside walls (30-40cm thick stone; no insulation). Never happened in last 5 years, and with ventilation, heating, and the dehumidifier in the worst rooms, it was sorted pretty easily.

I do however have a cold-house problem (given those thick stone walls), and while we've only had damp once or twice (and admittedly in areas I've now realised I need to keep aired, like an external north-facing corner I stupidly put a wardrobe onto), I do know that I'm basically just keeping it all at bay. I regularly ventilate, heat, etc.

Onto my stupid question - the 1.5 dehumidifier doesn't really pull much water. 8 hours in one of the 'worst' rooms, on an ordinary day, and it's maybe half a mug-full.

Question: does this mean my humidity isn't that bad? Or does it mean a bigger and better dehumidifier would pull out more?

Sounds like it's nowhere near powerful enough. Also some - desiccant dehumidifiers - tend to work better at colder temps so you might be better off with one of those.
But yeah I'd try something like a 20L desiccant one and pay a couple of hundred at least and see how you get on with that.

I had to double check what size mine is, apparently it's 10l. I definitely get more water if the room is warm versus if the heating isn't on. I have one upstairs that takes a turn in each bedroom, and another downstairs in the dining room/laundry. When the heating is on both tanks get nearly full when it's damp and cold outside.

https://www.argos.co.uk/product/8499493?clickSR=slp:term:dehumidifier:6:7:1

You need a certain amount of heat to get it to work efficiently. If it’s too cold you probably will draw less. Try turning the thermo up a bit

Personally, I would opt for a refrigerant type; I found it extremely effective.

Mine has a display that tells me the humidity levels - does yours not have this?

Mine goes into frost mode if it's below something like 14 or 15 degrees and then does bugger all. It works best at 30 degrees I found out after I bought it! (It's a Meaco and was recommended on here). If the temperature was 30 degrees I'd have all the windows wide open and not need a dehumidifier! Desiccant dehumidifiers are better at lower temperatures apparently.

This is the one I'd get next time:
https://www.robertdyas.co.uk/meaco-dd8l-junior-8l-desiccant-dehumidifier?cq_src=google_ads&cq_cmp=20381374449&cq_term=&cq_plac=&cq_net=x&cq_plt=gp&gad_source=1&gclid=Cj0KCQiAi_G5BhDXARIsAN5SX7pAajFRlyv84fFNXa97FnPQSXsph1TTmgJFff14k-m0kaF-1h9l-bsaAuCHEALw_wcB

Yes, you definitely need a different dehumidifier - half a mug in eight hours is almost nothing. Mine will suck an entire tank full out of the air in a humid room in that time.

Get a little humidity meter, OP, and then you'll know for sure how things are going. The small ones are really cheap.

A desiccant dehumidifier works fine in low temperatures and will give out a noticeable amount of heat. Our dehumidifier will collect 2 litres in 8 hours easily when drying clothes. It can be set to keep the humidity at a constant level.

I have an apartment built in 2006, and my dehumidifier will pull out a tank full in 24hrs if I'm drying laundry especially
I have a 20l black and decker one

IME there is a big difference between cheaper units and the more expensive. I got one from Amazon a few years ago for about £40ish. Took days to fill the 1.5l tank. Bought a ProBreeze dehumidifier, I think it's 12l with a 2l tank and it can fill the tank in 12hours. Was around £120 so about 3 times the price of the cheaper unit but so much more efficient.

I've now got a ProBreeze unit on each floor with a larger one in the laundry room, which I sometimes wheel around the ground floor. My husband thinks I'm obsessed but we've got a 1940s house and damp ground all around.

You need a humidity gauge otherwise you're just guessing

Buy some cheap digital hydrometers off Amazon, put them around the house and then strategically use a decent dehumidifier when you need to to tackle the spikes in humidity when they occur.

Cheap rubbish dehumidifiers are cheap rubbish dehumidifiers.

There are probably some half decent ones around at 1.5l, but there is probably also a lot of low cost tat. Half a mug full of water isn't any decent amount.

I would get a decent one like a meaco. But as someone else said, make sure it is compatible with the temperature you are trying to dehumidify (high temps compressor is OK, lower temps dessicant).

Love all of this, thank you so much, everyone! I've learned loads.

Ok, I've bought a couple of hygrometers off Amazon, which will arrive today. Agree that they will give me very useful information on how good or bad the situation actually is.

And I'm researching another dehumidifier to buy, which will be more powerful. Really appreciate the links people have shared, thank you!

The one I linked to above - my boiler is broken for a couple of days and it's been snowing outside so it's pretty cold in the house atm. I got nearly 5l from it yesterday plus it helped warm up the bedroom. Whichever you decide to go for just read the reviews about it first whether it's from argos, currys, JL or amazon. That's why I bought mine despite it being on the cheaper end for a decent one.