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Is It Dry Yet?

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Re: Is It Dry Yet?

#41
post #34

Earlier quoted context omitted.

This can cause issues with damp depending on your home and the local weather.

The water that was in your clothes and evaporated over 12 hours at night naturally is the same water that evaporates in 1 hour in the powered dryer. If you have working ventillation you're fine either way. If not - you're not. In fact I'd expect worse problems if you evaporate that same water quicker, because there's less time for it to escape outside.

Dryers typically are vented immediately outside via a dedicated tube and vent. That means that the air in the rest of the house never sees the moisture at all, so your whole-house ventilation system or dehumidifier doesn't need to work as hard.

Re: Is It Dry Yet?

#42
post #34

Earlier quoted context omitted.

This can cause issues with damp depending on your home and the local weather.

The water that was in your clothes and evaporated over 12 hours at night naturally is the same water that evaporates in 1 hour in the powered dryer. If you have working ventillation you're fine either way. If not - you're not. In fact I'd expect worse problems if you evaporate that same water quicker, because there's less time for it to escape outside.

Usually dryers are connected to dedicated ventilation out of the house, so the humidity doesn't transfer into your room directly. Otherwise, the laundry room would be a sauna.

Re: Is It Dry Yet?

#43
post #21

The cool thing about water is that evaporates all by itself. For free even. No electricity is required. So an alternative to making the tumble dryer "smarter" can be to simply not use it for most of the time, thereby cutting the loss caused by "dumb" dryers. The engineering part that's missing is related to re-introducing and improving the many awesome laundry line systems that used to be available.

Many British houses are already damp and small, and heating them to dry clothes doesn’t save energy. Putting clothes outside when it’s -2 degrees or raining consistently also doesn’t help. I think I’ve seen the kinds of indoor drying lines you are perhaps referring to, but I don’t know how compatible they are with Northern Europe.

Clothes can dry just fine when it's -30C outside, especially if there's some sunlight. It's the humidity that is a problem.

Re: Is It Dry Yet?

#44
post #39
post #21

Earlier quoted context omitted.

Many British houses are already damp and small, and heating them to dry clothes doesn’t save energy. Putting clothes outside when it’s -2 degrees or raining consistently also doesn’t help. I think I’ve seen the kinds of indoor drying lines you are perhaps referring to, but I don’t know how compatible they are with Northern Europe.

Dunno what counts as "Northern Europe", but in Poland nobody uses powered dryers, it's all natural. And it gets to -20 C in the winter here sometimes. Dry cold is not actually a problem for drying clothes.

Never heard of this. Doesn't the moisture just freeze in the clothes?

Re: Is It Dry Yet?

#45
post #7

My experience with "smart" driers is maybe less positive than others. Seems they typically only have one sensor in a rotating drum, if they "read" a t-shirt they will stop because it's "dry". But your jeans and your towel are not. Or, the sensors become intermittent, so you stop using the "smart" features.

I would naively assume the sensor would be a hygrometer measuring the humidity of the outgoing air. What kind of dryer do you have?

That's not it. The moisture sensor is two strips of metal on the inside of the dryer door that measure the conductivity between them or something.

Re: Is It Dry Yet?

#46
post #7

My experience with "smart" driers is maybe less positive than others. Seems they typically only have one sensor in a rotating drum, if they "read" a t-shirt they will stop because it's "dry". But your jeans and your towel are not. Or, the sensors become intermittent, so you stop using the "smart" features.

Even when I have a single blanket, it stops after a few minutes because one corner of it is dry while the inside is wet. I've had many loads develop mildew as a result. For large items even the "bulk load" setting with the max dryness doesn't reliably dry them throughout --- I have to manually put in "time dry" which is only accessible through the app.

Re: Is It Dry Yet?

#48

The cool thing about water is that evaporates all by itself. For free even. No electricity is required. So an alternative to making the tumble dryer "smarter" can be to simply not use it for most of the time, thereby cutting the loss caused by "dumb" dryers. The engineering part that's missing is related to re-introducing and improving the many awesome laundry line systems that used to be available.

> thereby cutting the loss caused by "dumb" dryers.

The loss that TFA and smart dryers are trying to cut is time spent on laundry. Having lived both with and without a tumble dryer, I'm very skeptical that there's a laundry line system out there that is less time consuming than even a dumb tumble dryer.

If there is one, I'd love a link!

Re: Is It Dry Yet?

#49

The cool thing about water is that evaporates all by itself. For free even. No electricity is required. So an alternative to making the tumble dryer "smarter" can be to simply not use it for most of the time, thereby cutting the loss caused by "dumb" dryers. The engineering part that's missing is related to re-introducing and improving the many awesome laundry line systems that used to be available.

We have clothes lines in our backyard and hang drying clothing is the bees knees. For one, dryers tend to ruin clothing. When I didn't know any better I'd dry black t-shirts on lowest heat setting and they're all washed out and didn't keep their color.

For some items like wool underwear and t-shirts I hang inside because sun bleaching can be a problem.

Re: Is It Dry Yet?

#50
post #39

Earlier quoted context omitted.

Dunno what counts as "Northern Europe", but in Poland nobody uses powered dryers, it's all natural. And it gets to -20 C in the winter here sometimes. Dry cold is not actually a problem for drying clothes.

Never heard of this. Doesn't the moisture just freeze in the clothes?

I think that there are two assumptions that we tend to make that causes the idea of air drying frozen clothes to be unintuitive:

1. We don't expect solids to evaporate, because it's not something we notice often (though if you think about the fact that a few inches of snow can disappear in a couple of days while the temperature remains below zero Celsius, you suddenly realize that you do observe it if you live in a cold climate)

2. We're so accustomed to using heat to speed the evaporation of water. So we might assume that removing large amounts of heat energy will "stop" evaporation. Or at least cause it to slow so much that air drying becomes impractical.

But ice does, indeed evaporate (to be accurate, it sublimates). My question is how temperature affects the speed of evaporation at low temperatures. How long do you need to leave your wet clothes hanging below freezing before they are dry?

https://phys.org/news/2018-10-sublimation-solid-ice-quickly-...

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