Dryer Efficiency

[Seasoned Oak]

Really, that's dangerous? We see 16% (lowest it will go) for a large part of the winter. I like it dry. Was always told to keep it low, under 50% RH or the dust mites will thrive.

At those levels several things happen here, dries out sinuses and promotes colds and other respiratory ails. We have had furniture split ,our tropical mahogany table split and cracked badly.

 

[iamlucky13]

The innternational residential code requires dryer vents to terminate outside the building, with a couple exceptions, such as for condensing dryers where the manufacturer has designed it to work without a vent.
http://www.greenbuildingadvisor.com...ing-code-questions/18918/dryer-venting-inside

The two big risks I can think of are humidity causing condensation (not likely to be an issue if the humidity is normally low, and it's not discharged into a relatively small, closed room), and either airborne lint to breathe in or settle everywhere or lint build up in an extra trap like those off-the-shelf indoor vents have. That's is a fire risk, but mitigated if the user cleans up any lint - something you already have to do with the trap in the dryer.

Taking into account those concerns, it doesn't seem like a big deal to vent indoors as long as you restore it to outdoor venting if you ever sell the house so an inspector doesn't flag it.

I'd never do it in my area because of the humidity.

 

[semipro]

Funny, this related article showed up in my email box today.
Its from GreenBuildingAdvisor.com
http://tinyurl.com/h9w28fw

 

[Seasoned Oak]

Is there any other restrictions such as venting under a porch deck. I have to vent a conventional dryer and the most accessible outside wall has a porch deck on th eother side where the cap would terminate. It is an open air deck with spaces between the boards and an open front. But its only about 2 ft off the ground.

 

[DanburyTreeCT]

Seasoned, Over here in CT there aren't any restrictions with venting under a porch deck.

 

[scotthershall]

The innternational residential code requires dryer vents to terminate outside the building, with a couple exceptions, such as for condensing dryers where the manufacturer has designed it to work without a vent.
http://www.greenbuildingadvisor.com...ing-code-questions/18918/dryer-venting-inside

The two big risks I can think of are humidity causing condensation (not likely to be an issue if the humidity is normally low, and it's not discharged into a relatively small, closed room), and either airborne lint to breathe in or settle everywhere or lint build up in an extra trap like those off-the-shelf indoor vents have. That's is a fire risk, but mitigated if the user cleans up any lint - something you already have to do with the trap in the dryer.

Taking into account those concerns, it doesn't seem like a big deal to vent indoors as long as you restore it to outdoor venting if you ever sell the house so an inspector doesn't flag it.

I'd never do it in my area because of the humidity.

My guess lint is highly flammable... When I moved into my house about 1.5 years ago, the first thing we had to purchase was a new washer and dryer because the previous owners took theirs (was a short sale, I think they needed the money but to their credit they never said it came with the house). Installing the new dryer I learned the last one was vented improperly. There was a vent cap on the outside but no actual vent piping from the drywall to the vent cap! The previous owners just stuck the flexible dryer vent into the drywall and called it good. After pulling out a mess of lint and fiberglass insulation and rodent excrement and acorn shells (from a 12" thick wall) I removed the old vent cap and installed a new one complete with an attached vent pipe.

Between that and all the other similar stuff (like the central air condensate line running straight down and touching the ground, causing it to back up almost instantly on a humid day - the air handler is in the attic) I'm surprised the house didn't burn down or sustain any other major damage during the 8 years the previous owners were there...

My most recent discovery... the town provides a nice 110PSI of water to the house. I just purchased a pressure reducing valve to be installed this weekend.

 

[Ashful]

Holy water pressure! Surprised you didn't get knocked clean off your feet each time you turned on a shower head.

 

[semipro]

the town provides a nice 110PSI of water to the house. I just purchased a pressure reducing valve to be installed this weekend.

Utility water pressure at a user is largely dependent upon the elevation of the user with respect to the elevation of the water in storage towers. They have to build to the supply adequate pressure to the highest houses so sometimes those at lower elevations will have higher than normal pressures. High pressure is certainly easier to address than low pressure though.

 

[DBoon]

the town provides a nice 110PSI of water to the house

Yeah, a condo I lived in had the pressure regulator fail and we were getting 140psi water pressure - I literally had water blowing past a faucet seal when I opened it up there was so much pressure.

 

[Lake Girl]

My guess lint is highly flammable...

A local couple lost everything due to a lint fire ... living quarters, store, and wedding gifts as they had only been married about a week. Lucky they got out ... dog woke them up.

 

[begreen]

A local couple lost everything due to a lint fire ... living quarters, store, and wedding gifts as they had only been married about a week. Lucky they got out ... dog woke them up.

That's really sad. We only run ours on low heat to reduce the chance of fire.

 

[Seasoned Oak]

That's really sad. We only run ours on low heat to reduce the chance of fire.

I only run low heat to save electricity ,it just takes a little longer to dry.

 

[jebatty]

I only run low heat to save electricity ,it just takes a little longer to dry.

Do you have a way to measure total electricity used before and after this strategy? Seems to me it takes X btus to evaporate water from a load of clothes, and that has to come from somewhere. Your strategy also likely is impacted by ambient relative humidity: high humidity will take longer to dry vs lower humidity. Obviously, drying outside takes 0 electricity, so using low heat and moving more air from the outside on a longer blower cycle may save energy.

 

[semipro]

I only run low heat to save electricity ,it just takes a little longer to dry.

Given that the drum motor and fan have to run longer on low heat mode I'm wondering if this might actually use more power per load.

 

[Seasoned Oak]

Given that the drum motor and fan have to run longer on low heat mode I'm wondering if this might actually use more power per load.

I would say its the same reason my Geospring HPWH saves so much power ,it may have to run longer than a traditional WH to recover but its consuming 500 watts instead of 4500 watts. Im sure the heating element in a dryer uses many times the power of the drum motor.

 

[semipro]

I would say its the same reason my Geospring HPWH saves so much power ,it may have to run longer than a traditional WH to recover but its consuming 500 watts instead of 4500 watts. Im sure the heating element in a dryer uses many times the power of the drum motor.

Its not the same.
The Geospring saves power because it captures ambient heat from the air as opposed to using using only resistance heat as in a conventional WH. It takes longer than conventional resistance heating only because doing it faster would take a larger refrigeration system that would be too large and cost too much.
Evaporating water from wet clothes requires a certain amount of heat per mass of water. Whether you do that slowly or more rapidly does not (necessarily) change the total amount of heat (i.e. energy) needed. I say "necessarily" because agitation and airflow affect the rate of evaporation also.

 

[iamlucky13]

The difference between a heat pump device and a resistance one is clear. It does seem possible, however, that simply relying more on air flow volume than on heat could save a small amount of energy. This would not be overwhelmingly difficult to test, if someone had a 240V power meter, and randomized which loads they ran which way.

 

[NickDL]

So here we are on a generally wood heating site, now discussing "green".
This Luddite spouts using a down comforter for example for the complaints about cold bedrooms.
Now another whine: does anyone hang clothes on an outdoor "line" anymore to dry naturally year-round ?
Why use fossils to dry clothes except in dire need for clean undies ? We need to know.
Lazy ?
Time constraints ( spend less time diddling on social media ) ?
Like efficiency and speed ?
Boy, those undies sure smell nice after outdoor naturale drying.

My wife hangs our clothes out as much as possible. She will also hang clothes in front of the wood insert, she really loves that. But there are plenty of times that she needs to use the dryer, especially when the weather is bad and she has run out of hanging space.

Sent from my Nexus 7 using Tapatalk

 

[Where2]

There's only one way to do laundry. Go big, or go home.

View attachment 182287

Nice to see I'm not the only guy with 2 front load washers and dryers in his house...

I've been working on a recently acquired rebuild project (a 2008 Samsung electric dryer) to drag to our farm. While I have it disassembled, I may spend some time investigating the main intake air locations, and what holes I need to seal in the chassis to limit surrounding air intake. This unit has a series of louvers on the back that may be intake air. My, nearly identical, existing Samsung electric dryer backs up to an exterior wall and vents directly through the same wall. If I could duct intake air to it rather than using conditioned room air, it might provide that "dried on a line" smell someone liked in their undies early in this thread, and increase the efficiency of my home.

For those who keep asking about measuring dryer efficiency, get a TED 1001, TED 5000, or even the (bare bones) Peacefair 100A kwh meter (with external CT). I've used all of those to measure 220V energy consumption.

While I was at the farm this summer, I spent plenty of time line drying my clothes, mainly because I was rearranging the room where the laundry units lived. There were definitely days where line drying didn't work, and several times when that little 120V apartment dryer my buddy dropped off came in handy sitting on the porch, vented out the window.

 

[Ashful]

Nice to see I'm not the only guy with 2 front load washers and dryers in his house...

I've been seeking out ways to increase my carbon footprint, in an attempt to prevent @woodgeek and @jebatty steering us clear of the "inevitable environmental apocalypse". As of this date, I've personally exceeded the average yearly energy consumption of Dusseldorf, and many other small European cities.

 

[begreen]

And on that dubious note closing thread.