Dehumidifiers, are they worth running? How big?

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#1956383 13-Feb-2018 15:02

Disagree that air con isn't needed. Even in Wellington we've had it running for the past couple months otherwise the house temperatures become very uncomfortable given what we're used to. Plus as it heats efficiently in winter it's a win/win.

Aredwood

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#1956474 13-Feb-2018 17:14

This night time heat has been the main problem for me. As it makes getting to sleep difficult. Also when temps normally drop at night. This forces a lot of the humidity to condense out. Which in turn helps to keep daytime humidity levels lower.

But with these hot nights, the humidity doesn't condense. And the current weather pattern is either rain / sun. with not much in between.

Ironically the weather in Auckland right now is like the weather in Samoa. (certainly feels like it).

TeaLeaf

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#1956643 13-Feb-2018 21:39

Yeah I hate this time of night too.

If you remove humidity, aircon is marginally needed in NZ, perhaps 2 weeks a year. If you can get 27deg at 50% humidity it honestly doesnt feel that hot inside.

Ive put the dehumidifier on at its gone from 95% to 65% in about 2 hours. Its much cooler but its saying its still 24 degrees inside.

Auckland feels hot but its only 27 degrees. but it averages of 80% humidity every month, often over 90. The human body requires 40-60%. Anything over 70 and nasties like Asthma is a serious problem via all kinds of issues like mould, and damned book mites which love its around 80%, they die off below 60.

Air Con in Aus is needed because 45 degrees and 90% humidity.

The Air Con just cools your air, whats it doing for your health? If you must have Air con which after having had different types of humidty removal like HRV, I dont think its a need, you still need air purification, this is where Im not such a fan of air con.

Air con in welli ROFL. Thats a juxtaposition. Dont you mean you need central heating all year round and balloon around the house to keep the wind at bay. Jokes.

richms

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#1956660 13-Feb-2018 22:08

I have aircon, I like aircon. I dont "need" it but I dont need lots of things that I like.

Its quieter than a dehumidifier, Im not constantly sweating like if it was 27 and dehumidified. It's more pleasant. Easily the best money I spent on the house.

Richard rich.ms

Starscream122

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#1956662 13-Feb-2018 22:21

Just plugged in the dehumidifier and it started warming my room up. I have unplugged it and put it back away.

Hammerer

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#1956677 13-Feb-2018 23:15

The optimal temperature for working / thinking / good decision making is lower than the temperatures we've been having in Wellington metro areas for most of the past two months. So it would be relatively easy to make an economic case for air conditioning for a workplace or household. More so in Auckland where the relative impact of higher temperatures is increased by higher humidity levels.

For guidance see https://worksafe.govt.nz/dmsdocument/776-what-you-need-to-know-about-temperature-in-places-of-work or one of many other easy to find references.

Aredwood

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#1956694 14-Feb-2018 01:18

Starscream122:

Just plugged in the dehumidifier and it started warming my room up. I have unplugged it and put it back away.

This was why I didn't recommend a dehumidifier for summer use. As every litre of water that a dehumidifier removes from the air, adds an extra 0.6KW/Hr of heat to the air. Due to the latent heat of water and water vapour. Plus the waste heat produced by the motor and other parts inside the dehumidifier. In winter this is useful, as it means that you get some free heat by using a dehumidifier (especially if you are renting, or another reason means that you can only otherwise use plug in heaters for heating).

But not good in summer, as the total heat output of a dehumidifier in really humid conditions could be as much as 1KW/Hr. (latent heat + waste heat)

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Starscream122

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#1956703 14-Feb-2018 05:58

It is also a very old dehumidifier so I would guess it's parts would produce a lot of waste heat compared to the newer models. it only

took about 20 mins on high I could tell it was starting to heat the room ( small room)

Dairyxox

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#1956725 14-Feb-2018 08:23

I don't think a dehumidifier is worth it.

It would be better to get an air conditioner unit.

Dehumidifiers use quite a lot of power, but don't deliver the other efficiency/heating/cooling benefits of aircon. They're normally noisy too. May as well get aircon.

When I had one in the past, you had to run it for hours to feel any difference, and 10 minutes after you turn it off the humidity returns with a vengeance.

Starscream122

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#1956733 14-Feb-2018 08:56

Air Conditioning also uses quite a lot of power....

tkgit

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#1956819 14-Feb-2018 09:58

if your home don't have AC and/or HRV(or humidity control) you have to use dehumidifier,

I've tested 2 home using humidity sensor,

the home which have AC&HRV usually has 30%-50% humid & I never saw dampness in the corner of the windows,

another home without AC&HRV, if I didn't use dehum(just electric heater), in the morning a lot of dampness on the windows, but if used dehum for 1h everyday(usually in the morning), just small in the corner, the sensor showed 50%-80%

TeaLeaf

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#1956829 14-Feb-2018 10:12

Dairyxox:

I don't think a dehumidifier is worth it.

It would be better to get an air conditioner unit.

Can you recommend one that demumidifies the current air but leaves it not TOO dry ie 50-60% humidity. Can you recommend one that filters the air? Can you recommend one that the filter is washable? ;-p

Oh also it needs to be portable so I can stick it out the windows and cover the gap.

im RENTING. im not installing a reverse cycle air conditioner in somebody elses property sigh.

Sure if all you want is to feel cool for the 2 days of the year that its actually hot in most of NZ, buy an air conditioner. or add a teaspoon of cement to your coffee :-)

This isnt about heat its about humidity and health.

What good is a non reverse cycle portable air con to me in winter when its still the same humidity, hence why we allow as a nation our poor to have chidren die of breathing disorders related to dank conditions. Im sure air con would have helped them.

Like I said, I like air con too, I just dont need it in NZ, its not hot enough. I lived in Darwin and 55 degrees is hot, but Cairns is worse as I think its even more humid being full tropical ie 100% humidity 50 degrees in summer, the conditions they rate the dehumidifiers for ie 16l 22l etc, you only get that amount out of tropical rain forests.

Im very happy with the dehumidifier, its got us down to 60% in one night in the whole house, we have moved it round, surprised how much water furniture holds. Most of all Im glad we are cleaning the air of pollutants and disease and will do all the way through winter.

My Mrs house in Germany they dont use air con and gets to 38 where they live. They have a HUGE home which is very stately, but its also fairly high tech with one of those automatic recyclable chip boilers for central and below floor heating. Everything is made from Euro marble, slate and granite. They have triple glazed windows (wow I was amazed you can shout outside and not be heard), automatic lighting, automatic TV pops up etc, auto blinds set to a seasonal alogrithm. It just blew me away how BAD the quality of housing in NZ is if thats the medium wealth there.

And they dont use air conditioning. They do have an HRV type air purifier, hard to explain as I havnt seen one here.

Aredwood you can get portable air cons you just stick the hose out the window, they really good for a bedroom, that might suit you? But you only have a couple weeks of heat left. If I knew I was renting for life, I would buy one of those and run a dehumidifier on air cleaning mode.

timmmay

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#1956834 14-Feb-2018 10:17

Starscream122: Air Conditioning also uses quite a lot of power....

It's totally worth it when you want it though. We heat the house to 22 degrees 16 hours a day in winter, and keep it reasonable in summer, running air-con 12 hours a day or more this summer. Average house, old, well insulated and double glazed. Winter we pay about $50 - $70 a week, summer $30 - $50, for 2 adults one infant.

TeaLeaf

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#1956837 14-Feb-2018 10:21

tkgit:

if your home don't have AC and/or HRV(or humidity control) you have to use dehumidifier,

Thank you, I agree. Im not arguing some people cant handle high 20s heat, but that doesnt change air humidity and purification.

Those reverse cycle units that sit on the wall? NO THANKS.

I owned a beautiful place overlooking a surf resort in NSW. It was a town house, but like my Mrs parents place it was made all with stone, it makes such a huge difference to not just heat by condensation in the walls. the floors were italian Marble and the view from the upstairs Balcony or even my Bedroom was amazing, but some days it was 40 degrees outside, so on went the AC, but the AC is ducted into every room through the roof.

I didnt have a dehumidifying system but being in a place where sunlight annoys you after a while I never saw the likes of mould, and 17 was middle of winter.

NZ is DANK. We need to lift our game on our thoughts of home air quality imo.

TeaLeaf

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#1956838 14-Feb-2018 10:21

tkgit:

if your home don't have AC and/or HRV(or humidity control) you have to use dehumidifier,

Thank you, I agree totally. Im not arguing some people cant handle high 20s heat and desire air con for a few weeks a year.

Those reverse cycle units that sit on the wall that were suggested? NO THANKS. That doesnt improve quality of air.

I didnt have a dehumidifying system but being in a place where sunlight annoys you after a while I never saw the likes of mould, and 17 was middle of winter.

NZ is DANK. We need to lift our game on our thoughts of home air quality imo.

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