# How much energy is your dryer wasting?



## Badfish740 (Feb 28, 2011)

I had a lot of hard metal duct (as in not the flexible stuff) left over from re-routing the ductwork in my basement to the sides rather than right down the middle to make more headroom.  I had been wanting to upgrade from the cheap tin-foil crap that the previous owner of our house had used to vent the dryer to the outside.  This job was particularly bad (splice in the middle, excess length, crappy cap on the outside, etc...) but it was just another one of those things that after three years in the house I still hadn't gotten to.  Yesterday I took two 4" elbows and a long section of 4" pipe that used to deliver air to the bathroom from the main trunk line and combined them with a dryer vent I bought at Lowes.  The old vent pipe was a fire waiting to happen, plus the buildup had slowed the airflow down to a crawl.  Now the airflow is significantly stronger and clothes dry a lot faster.  Granted I had most of the materials laying around so it hardly cost me anything, but to buy the materials brand new would still be very cheap.  The energy savings are great as well as the safety factor.


----------



## Jags (Feb 28, 2011)

Badfish - sounds like a good job to me.  If nothing else, this is a good reminder to those that ignore the dryer vent as a maintenance item.  These things should be looked at annually, both for a safety issue and for the efficiency of the operation.


----------



## Highbeam (Feb 28, 2011)

I have built in cabinets around my washer dryer so to access the ducts I need to slide out the machines. That is bad for maintenance. Worse yet is that since you must hook up the duct before shoving the dryer into its cubby, there ends up being a long length of flex duct coiled up on the floor. A lint accumulation problem for sure. I recently cut an access through a cabinet to see the water shutoffs and I noticed that I could seriously shorten the flex duct. 

So I'm considering a rebuild as you describe. It shortened dry time? Significantly?


----------



## Badfish740 (Feb 28, 2011)

Highbeam said:
			
		

> It shortened dry time? Significantly?



The airflow out of the pipe increased significantly-the drying time decreased, but I wouldn't call it dramatic.  As an example, with the old pipe in place if you put a full load of clothes in on high and set it to 50 minutes, usually some of the clothes would come out only "semi-dry" (ie: on a pair of pants most of the pants would be dry, but the insides of the pockets would be damp), and you'd have to put the load back in for an additional 15-20 minutes to completely dry it.  Now the clothes come out dry in one 50 minute cycle.


----------



## pyper (Feb 28, 2011)

When we moved into our last house, the dryer vented into the crawl space. I put in a hard metal duct. When we had some work done on the house, the guys who did it replaced the hard metal duct with flexible duct. I don't know if we noticed a difference in dryer time or not.

But here's something I do every few months. I got a dryer vent brush. It's a flexible thing, about 10 feet long, kind of like the coiled thing shown here:

http://www.bedbathandbeyond.com/pro...ogle&utm_medium=organic&utm_campaign=shopping

So I took that and cut off the handle. Then I bent the end of it, because the thing was like 3" around, but we have 4" duct. I put the end in my cordless drill, and feed it into the duct as far as it will go from the outside. Then I go in and turn on the dryer and go back out and turn the drill on, while moving the thing in and out of the duct. It's amazing how much lint you can clean out. Once a year or so I pull the dryer out, disconnect the vent on the inside and do a similar cleaning (obviously without the dryer going).


----------



## Badfish740 (Feb 28, 2011)

earlll said:
			
		

> I heard that grounding the metal duct reduces lint buildup?



Interesting idea-I could see it working on the smooth metal duct I installed but the flex stuff has too many nooks and crannies for it to get lodged in I think.


----------



## yooperdave (Mar 1, 2011)

one more thing to think about- use only aluminum pipe/not galvanized. it takes longer to heat up the gal. pipe to vent the waste out as opposed to alum. also, with alum being lighter, you are able to foil tape the pipe joints. with gal, you may be tempted to use screws for the pipe joints. the part of the screw on the inside of the pipe immediately becomes a lint catcher


----------



## btuser (Mar 1, 2011)

yooperdave said:
			
		

> one more thing to think about- use only aluminum pipe/not galvanized. it takes longer to heat up the gal. pipe to vent the waste out as opposed to alum. also, with alum being lighter, you are able to foil tape the pipe joints. with gal, you may be tempted to use screws for the pipe joints. the part of the screw on the inside of the pipe immediately becomes a lint catcher



Is it because of the guage?  

My dryer vent is about a foot long, including the space it takes to get out of the house.  Once we switched to a front load washer the drying time was cut down by 2/3.


----------



## yooperdave (Mar 1, 2011)

btuser said:
			
		

> yooperdave said:
> 
> 
> 
> ...



man, talk about your ideal situation!  mom's is like that also.  when i got the dryer termination, it came with a aluminum pipe attached to the plastic termination.  positioned the dryer, ran a spotter bit through the wall, enlarged the hole to 4", slid the termination with pipe attached right onto the back of the dryer-bingo!
however, when the dryer is located in the basement or can't be vented in  such an easy method, its time to start running aluminum pipe and elbows-typically, not more than 3 elbows (90's) in the run.

on that short of a run (one foot) you could sneak by with galvanized.  but i didn't......


----------



## Highbeam (Mar 1, 2011)

Since the dryer is grounded vis the chassis ground, and so long as you use metal ducting, I would think that the ducting is also grounded. If you use that white, plastic, felx stuff it usually has a metal wire in it that can be exposed where it is clamped.


----------



## Highbeam (Mar 1, 2011)

I can't believe that anybody still has a dryer that uses a timer instead of a moisture sensor. It must be decades old. Imagine, for a moment, a dryer that stops wasting energy as soon as the clothes are dry. We also noticed a major drop in dry time after moving to a front load high speed spin washer. Unfortunately, the thing has had to be repaired twice now. Once for a busted belt and again for a clogged pump, seems you are supposed to use a big mesh bag to hold your socks.


----------



## jharkin (Mar 1, 2011)

Highbeam said:
			
		

> I can't believe that anybody still has a dryer that uses a timer instead of a moisture sensor. It must be decades old. Imagine, for a moment, a dryer that stops wasting energy as soon as the clothes are dry. We also noticed a major drop in dry time after moving to a front load high speed spin washer. Unfortunately, the thing has had to be repaired twice now. Once for a busted belt and again for a clogged pump, seems you are supposed to use a big mesh bag to hold your socks.



Most dryers that have a n auto settings still have the timer. 

Our dryer has both. I use auto.  My wife absolutely refuses too as she wants to know exactly when the run will finish so she can take the clothes out warm and fold before they wrinkle.

Dont even ask about listening for the buzzer. I stopped trying to use logic in spousal arguments years ago and am less stressed for it


----------



## joecool85 (Mar 1, 2011)

My dryer has a straight 16" run of pipe from the back of the dryer to the vent that is outside.  I like having less than 1.5 ft of pipe, it's wicked easy to clean and doesn't get very gross to begin with.  Now, my folks have 20', that's right FEET of pipe.  THAT gets gross and clogged.


----------



## Dingeryote (Mar 1, 2011)

Not much really. More by chance than design though. 
When we built the house the plan was to put the washer and dryer in the basement, but a change in one bathroom, left room on the main floor with the dryer next to an outside wall.
Just a foot long run of stainless(Leftovers from the produce handling operation) and one elbow duct. 
Heck for a clean out, I use a 20Ga bore brush on a cleaning rod, and just spin it around inside the run from the flapper chute outside.

The downside is it's at the front of the house, and occaisionally the wifes posies and plants get lint blown all over them.

I hate the sensor dry function our GE front loader. It seems to think "Moist"is dry, even when set for max dry.
Had the repair tech out several times under warranty to address the problem and it's just a design flaw, so we end up running another sensor cycle after the first in the winter.
Summertime the clothes line gets used. We aren't greenies by any stretch, just frugal.


----------



## pyper (Mar 1, 2011)

jharkin said:
			
		

> Our dryer has both. I use auto.  My wife absolutely refuses too as she wants to know exactly when the run will finish so she can take the clothes out warm and fold before they wrinkle.
> 
> Dont even ask about listening for the buzzer. I stopped trying to use logic in spousal arguments years ago and am less stressed for it



We got a new Samsung dryer. It's cool. Unfortunately you can't hear the "buzzer" which is really a chime, if you're more than one room away, and/or have the TV on.

But it does have a "wrinkle prevent" feature. After the clothes are dry it stops, but then every once in a while it gives them a tumble. Until they're completely cooled. This would be twice as great if you had a smart meter and could dry your clothes on the cheap rate.

The other nifty feature is a steam setting. If you do have clothes that are wrinkled, you can steam them. Probably less energy than ironing.


----------



## dougstove (Mar 2, 2011)

I put on one of the vent assemblies (Broan, I think) with a floating styrofoam ball that blows up out of the way when the dryer is venting, and falls back to block the hole when it is not venting.
It made a big difference to the winter time temperature of the dryer;  keeps the room a good bit warmer.
Unfortunately the ball holder assembly is a bit delicate and lint clean out must be done carefully.


----------



## jimbom (Mar 2, 2011)

btuser said:
			
		

> yooperdave said:
> 
> 
> 
> ...



Are you saying the front load washer loads are easier to dry?  I do not know anything about the front load washers.


----------



## jimbom (Mar 2, 2011)

jharkin said:
			
		

> Highbeam said:
> 
> 
> 
> ...



I normally let the spouse stuff go in one ear and out the next, but last summer she made a comment that sort of made me think.  After I had cleaned the dryer vent, she said I still don't think the dryer is working correctly.  Something about the offhand way she said it made me think, so I pulled the front panel on our dryer and started looking inside the thing.  I about crapped.  The internals on our dryer were plugged with compacted lint.  The blower housing, air passages etc.  I had never cleaned them, thinking the vent was all I needed to keep clean.  Guess I am lucky we didn't have a fire.  At my age, you would think things around the house would no longer be surprising me.  Something bad going on with my maintenance or frequency on the vent.  In any case, the dryer itself will get checked when I do the vent in the future.


----------



## joecool85 (Mar 2, 2011)

JimboM said:
			
		

> btuser said:
> 
> 
> 
> ...



Front load washers spin out a lot more moisture before they are done, so there is less water than needs to come out in the dryer.  They are a big electricity saver, but pretty expensive up front cost.


----------



## Seasoned Oak (Mar 2, 2011)

Anyone needing to use a humidifier in winter would benefit from venting the dryer to another lolcation INSIDE the house. ITs saves on heat as well. My indoor humidity hovers around 23% in winter. Drier than a desert.


----------



## TMonter (Mar 2, 2011)

joecool85 said:
			
		

> JimboM said:
> 
> 
> 
> ...



Actually the new upper end agitatorless top load washers are just as good as the front loaders and a few hundred less than a front loader. They're also direct drive like many front loaders.


----------



## joecool85 (Mar 2, 2011)

TMonter said:
			
		

> Actually the new upper end agitatorless top load washers are just as good as the front loaders and a few hundred less than a front loader. They're also direct drive like many front loaders.



Neat, I hadn't even heard of that type yet.  Learn something new every day.


----------



## SmokeyTheBear (Mar 2, 2011)

joecool85 said:
			
		

> TMonter said:
> 
> 
> 
> ...



Our Gibson top load washer bit the bullet last October (and while I could have repaired it and turned the air many colors while doing so), we replaced it with one of the new top load, low water, Maytag washers.  So far so good, it doesn't use or leave anywhere near the amount of water the other one did.  You have to be certain you put the detergent (he compatible) in the washer first.  The replacement shortened our laundry time as the dryer doesn't have to work as hard.

I've got to pull both the washer and dryer out to clean things out these days, darn basement laundry, used to have things direct vented with about a foot of pipe at the other house.  

Maybe I could take a clue from pellet stove cleaning and rig up an adapter so I can use a leaf blower.


----------



## RustyShackleford (Mar 21, 2011)

Badfish740 said:
			
		

> The energy savings are great as well as the safety factor.


Two other wins (for cleaning out and/or upgrading your drver vent):

- it puts less wear&tear; on your clothes, since they're exposed to the heat and tumbling for less time

- it's more convenient (not having to wait so long for your clothes to be dry)


----------



## semipro (Mar 21, 2011)

SmokeyTheBear said:
			
		

> joecool85 said:
> 
> 
> 
> ...



That's a great idea using the leaf blower for that.   I use ours to clean our gutters and used it last weekend to clean the interior of my truck.  I just upened all the doors and let her have it.


----------



## joecool85 (Mar 21, 2011)

Semipro said:
			
		

> That's a great idea using the leaf blower for that.   I use ours to clean our gutters and used it last weekend to clean the interior of my truck.  I just upened all the doors and let her have it.



I need a leaf blower...now I have an excuse.  I mean, reason


----------



## Slow1 (Mar 21, 2011)

I'm really curious just exactly how much electricity a dryer uses per load.  I'm sure it varies (lots of factors) but I wish I could get an average.  I have one of those "kill-a-watt" devices but of course it is only useful for standard plugs (not the mega-high watt plug types on the dryer).

In any case - having now put up clothes lines in the house near the stove we have saved a lot of electricity (only used the dryer during a 2 day period so far this year when the kids were sick - vomiting overloaded our drying capacity..) and as a bonus it has added a lot of humidity to the air.  Have to plan a bit better - we do 4-5 loads a week (4 kids - lots of laundry) so we have only 2-3 days a week that a load doesn't get washed/hung to dry.

I'm not sure that we'll be able to keep it up all year though - getting to be too warm to burn at night (drying time) and not warm enough to hang clothes outside and expect them to dry.  Guess we'll just have to burn the electrons again until it warms up enough to hang outside.


----------



## Dune (Mar 21, 2011)

Older dryers drew 5800 watts. Newer ones draw 5000 watts.


----------



## RustyShackleford (Mar 21, 2011)

Dune said:
			
		

> Older dryers drew 5800 watts. Newer ones draw 5000 watts.


Of course the heating element does not run continuously


----------



## begreen (Mar 21, 2011)

And it doesn't have to run on high. We almost always run it on low.


----------



## fishingpol (Mar 21, 2011)

JimboM said:
			
		

> jharkin said:
> 
> 
> 
> ...



Electric dryers have several thermal cut-off switches that would shut the dryer down when temps get excessive from a clogged vent or internal passage.  There are usually two on the upper rim of the heater coil and a few by the blower assembly.

Another good thing to do is remove the lint screen every month or so and run it under hot water to remove any built up fabric softener that can clog it.  You really have to look close at it to see that it is blocked.


----------



## henkmeuzelaar (Mar 21, 2011)

Dune said:
			
		

> Older dryers drew 5800 watts. Newer ones draw 5000 watts.



Good info!  
If correct, most of us should typically use between 2 and 6 kWh of electric energy per dryer load. 
Depending upon one's electric power rates, this would then cost us anywhere between 0.1 and 1.0 US $.

Now comes the kicker, though. Unless I found the wrong numbers it looks as if the typical dryer blower has a 500-1500 cfm capacity. So, let's assume we may blow as much as 50,000 cubic feet of warm house air into the outside world per (big) dryer load. This equals about 1,350 cubic meter, or roughly 1,350 kilograms of air.  

On a cold day, we may have to heat the replacement air by 40F or so.  It takes about 1 kiloJoule to heat 1 kg of air by 1 degree Kelvin.

Unless I screwed up the math, I am finding that reheating all that air by 40 deg F will cost about 8 kWh (~ 27,000 BTU) , or so.....   

Please Lord, let me be wrong...... (I am in a bit of a hurry and don't have time to carefully check my calcs).  However, if I am not, we may be paying more (on a cold day) to reheat all the air we blew off through that dryer than we are paying to run the dryer in the first place

In case you were thinking: "well we need to ventilate the house anyhow.....", let me point out that a 1,000 cfm dryer-type "home ventilator" blows at least 10 times more air than the recommended ventilation ("room air turnover") rates for your average 20,000 cubic feet home. 

Moreover, few if any homes are wired in such a way that the forced home ventilation via the dryer is somehow subtracted from what the "whole house fan" is programmed to do every day......

Have fun!

Henk


----------



## joecool85 (Mar 21, 2011)

That sounds about right.  28k btu in oil for me with a 86% efficient furnace would be 1/3 gallon of oil.  That's about $1.25 right now per load of laundry in heating oil, plus the electricity.  For us with the low heat dryer setting and the $0.14 kwh rate that means we use about $0.36 in electricity.  A total of $1.61 per load.  Luckily we hardly ever run the dryer winter or summer unless it's raining.  In the winter we hang our clothes inside and the super dry Maine winter air dries our clothes within a day or two.  In the summer they are hung outside.  I suppose this is how we manage a sub $50 per month electric bill.


----------



## Slow1 (Mar 22, 2011)

Sort of makes me wonder why they don't have OAKs for the dryer... in winter it would then pull in cold (and very dry) air to dry the clothes.  Even if the air wasn't heated to a particularly high temperature as a result, it would in theory dry just as fast (perhaps even faster) than using air from inside the house that is likely of a higher relative (and absolute?) moisture content. 

I'm sure there are reasons...

Thanks for that number - 2-6Kwh per load... so if I'm avoiding 5 loads per week then I'm saving between 10-30Kwh of electric a week (40-120Kwh/mo).  That's quite a bit to me - I average 514Kwh/mo so that is something like 8-23% in savings.  I expect given that I have a front loading washer that spins very well I'm likely much closer to the lower end of that spectrum, but that is still significant.


----------



## henkmeuzelaar (Mar 22, 2011)

joecool85 said:
			
		

> That sounds about right.  28k btu in oil for me with a 86% efficient furnace would be 1/3 gallon of oil.  That's about $1.25 right now per load of laundry in heating oil, plus the electricity.  For us with the low heat dryer setting and the $0.14 kwh rate that means we use about $0.36 in electricity.  A total of $1.61 per load.  Luckily we hardly ever run the dryer winter or summer unless it's raining.  In the winter we hang our clothes inside and the super dry Maine winter air dries our clothes within a day or two.  In the summer they are hung outside.  I suppose this is how we manage a sub $50 per month electric bill.



Nah. Thanks for the moral support!  However, my calculations have to be wrong somewhere. After all, if it would cost 8 kWh to reheat all the outside air by 40 F, then it should be double that for heating that same amount of air by 80 F or so inside the dryer.... And this is not even counting the power needed to run the fan/drum motor, as well as to evaporate and heat all that water.

I think what's happening is that a typical dryer fan never reaches its maximum cfm rating because of the resistance in the vent pipe/hose. My guess is that the 50,000 or so cu.ft. of air blown through the dryer for 1 heavy load that I estimated (i.e. almost 3,000 pounds worth!) is probably more like 10,000 to 20,000 cu ft. Still more air than any of us can lift, but more in line with the inside heating requirement side of the equation.

Henk

edit: also, I should have corrected for the ~15 % lower density of the hot air inside the dryer!


----------



## Dune (Mar 22, 2011)

PyMS said:
			
		

> Nah. Thanks for the moral support!  However, my calculations have to be wrong somewhere. After all, if it would cost 8 kWh to reheat all the outside air by 40 F, then it should be double that for heating that same amount of air by 80 F or so inside the dryer.... And this is not even counting the power needed to run the fan/drum motor, as well as to evaporate and heat all that water.
> 
> I think what's happening is that a typical dryer fan never reaches its maximum cfm rating because of the resistance in the vent pipe/hose. My guess is that the 50,000 or so cu.ft. of air blown through the dryer for 1 heavy load that I estimated (i.e. almost 3,000 pounds worth!) is probably more like 10,000 to 20,000 cu ft. Still more air than any of us can lift, but more in line with the inside heating requirement side of the equation.
> 
> ...



Even if your math is not perfect it is still enlightening. Definitely makes a case for outside air.

I posted this years ago here, but it bears repeating; I replaced my dryer vent with 4" PVC pipe. The smooth inside surface helps maintain air velocity as well as keeping clear of lint readily. The drying time was noticably shorter versus the old dented corro-aluminum vent. Note that I have an electric dryer.


----------



## pyper (Mar 22, 2011)

PyMS said:
			
		

> [
> Nah. Thanks for the moral support!  However, my calculations have to be wrong somewhere. After all, if it would cost 8 kWh to reheat all the outside air by 40 F, then it should be double that for heating that same amount of air by 80 F or so inside the dryer.... And this is not even counting the power needed to run the fan/drum motor, as well as to evaporate and heat all that water.



It's still really interesting.

I have noticed that when we run the dryer, the rooms between it and the stove are warmer -- because it's pulling air through the house. Same thing with the bathroom exhaust fan. If they both run for a while, you can actually feel a path of warmer air.


----------



## mayhem (Mar 22, 2011)

Highbeam said:
			
		

> I can't believe that anybody still has a dryer that uses a timer instead of a moisture sensor. It must be decades old. Imagine, for a moment, a dryer that stops wasting energy as soon as the clothes are dry. We also noticed a major drop in dry time after moving to a front load high speed spin washer. Unfortunately, the thing has had to be repaired twice now. Once for a busted belt and again for a clogged pump, seems you are supposed to use a big mesh bag to hold your socks.



I for one have never heard of a dryer that has a moisture sensor.  But then again, my dryer is a good 10 years old and it was the $300 model.  TImer, couple heat settings and not much else.  Does the cost of moving up to a moisture sensor dryer cover the energy savings over its lifetime thoguh?


----------



## pyper (Mar 22, 2011)

mayhem said:
			
		

> I for one have never heard of a dryer that has a moisture sensor.  But then again, my dryer is a good 10 years old and it was the $300 model.  Timer, couple heat settings and not much else.  Does the cost of moving up to a moisture sensor dryer cover the energy savings over its lifetime though?



I don't think you can buy a new dryer without -- even the cheapest model ($224) at HD has one.


----------



## Exmasonite (Mar 23, 2011)

Very interesting thread... 

I wonder if it should be titled "How much energy is my clothes line saving?"  

Sure, it's not really the weather for it but we got a new, front loading dryer in the fall and have found that when the weather is nice, we hang the clothes out on a line on our balcony.  Some of the clothes we'll throw in the dryer on the "steam refresh" cycle for 10-15 minutes before folding or wearing.  Sure, takes a little more time and effort but i think it saves a fair amount of energy.  Don't really have a good "control" to look at this scientifically.  

Btw, on a side note, anybody have any experience with one of those heat diverters like this one at amazon?  We had a mold issue in our attic and the washer/dryer is on the 2nd floor so i'm a little hesitant to expose the household to excess moisture but always looking for a way to save $$ on heating the house.


----------



## Slow1 (Mar 23, 2011)

Exmasonite said:
			
		

> Very interesting thread...
> 
> 
> Btw, on a side note, anybody have any experience with one of those heat diverters like this one at amazon?  We had a mold issue in our attic and the washer/dryer is on the 2nd floor so i'm a little hesitant to expose the household to excess moisture but always looking for a way to save $$ on heating the house.



My folks who live in CO (VERY dry area) use on and believe it is a very good thing for them.  They believe it has added quite a bit of humidity to the house but not excessive amounts in the area where it vents - i.e. they have no mold concerns.  Then again, it is just the two of them and I think the average relative humidity is less than 40% most of the time anyway (year round).

If you have issues in your attic, you may be well advised to investigate air leaks into the attic from the house - that is where the moisture is most likely coming from.  Seal up those air leaks and the whole house will be more efficient as well as solving the attic problems.  Win-win situation if there ever was one.  Of course I'm assuming you aren't venting anything into the attic (big mistake there naturally).


----------



## mayhem (Mar 23, 2011)

In the winter I use an indoor lint trap for my dryer vent and run it directly into the basement air.  The basement is by far the coolest and dryest room in the house, so adding heat and moisture for 40 minutes at a time a few times a week is a good thing.  Beware that anything that goes inline in a dryer vent is a potential lint trap and needs to be checked regularly, cleaned if necessary.



> I donâ€™t think you can buy a new dryer withoutâ€”even the cheapest model ($224) at HD has one.



Cool, learn something new every day.  My 10 year old dryer definitely does not have one...or if it does its not advertised on the unit, nor is there an auto dry setting available on it...you can run the thing for as long as you want and it oesn't matter how dry your clothes are...it'll keep running.


----------



## lukem (Mar 23, 2011)

Exmasonite said:
			
		

> Very interesting thread...
> 
> I wonder if it should be titled "How much energy is my clothes line saving?"



Same here.  We haven't used our dryer in over a year.  In the winter we have a clothesline in the basement (where the stove is) and it dries clothes quickly.  In the spring summer they go outside.

In addition to electricity costs, it is much easier on your clothes and they last longer.


----------



## nate379 (Mar 23, 2011)

I have wondered as well.  My house is sealed up well enough that if the dryer is running and anything else that draws air from teh house (bath fan, kitchen stove fan, etc) I have to crack a window open or it backdrafts the woodstove.



			
				Slow1 said:
			
		

> Sort of makes me wonder why they don't have OAKs for the dryer... in winter it would then pull in cold (and very dry) air to dry the clothes.  Even if the air wasn't heated to a particularly high temperature as a result, it would in theory dry just as fast (perhaps even faster) than using air from inside the house that is likely of a higher relative (and absolute?) moisture content.
> 
> .


----------



## Highbeam (Mar 23, 2011)

Seriously Nate, you are in AK and not using an OAK on your BK? Your house must not be as tight as you think. Seems like the farther north you are the more you would benefit from an OAK since every bit of air that your stove blows up the chimney is cold and DRY outside air leaking into your home. Humidity control is a big benefit of OAK.

I wonder why they haven't put an intake duct on dryers yet. Perhaps this will be the next big thing like when they started adding intake systems for water heaters and furnaces. Has anybody looked on their dryer to see if it is possible to add a duct to the intake?


----------



## Exmasonite (Mar 23, 2011)

We figured out the mold issue-  at some point ~ 2 yrs ago (probably when the roofers were up there the previous owners surmise) the dryer vent was disconnected and spent 1-2 yrs venting moist air into the attic which caused the mold.  It was professionally mitigated prior to our purchase (and the dryer exhaust repaired) but we're still a little wary about it.


----------



## semipro (Mar 23, 2011)

Highbeam said:
			
		

> I wonder why they haven't put an intake duct on dryers yet. Perhaps this will be the next big thing like when they started adding intake systems for water heaters and furnaces. Has anybody looked on their dryer to see if it is possible to add a duct to the intake?



I've wondered this too.  I've also wondered if driers could be built with a heat exchanger, extracting heat from exiting air and adding it to incoming air, in function like a a Heat Recovery Ventilator.

Seems I need to tear my drier apart to clean per someone else's advice here so I may have a look then.


----------



## semipro (Mar 23, 2011)

mayhem said:
			
		

> In the winter I use an indoor lint trap for my dryer vent and run it directly into the basement air.  The basement is by far the coolest and dryest room in the house, so adding heat and moisture for 40 minutes at a time a few times a week is a good thing.  Beware that anything that goes inline in a dryer vent is a potential lint trap and needs to be checked regularly, cleaned if necessary.
> 
> 
> 
> ...



I'm surprised they sell dryer's without the moisture sensor option.  I've noticed on the two that we've had that they have a metal looking sensor that makes contact with the clothes as they tumble.  I'll bet that's the moisture sensor.


----------



## Highbeam (Mar 23, 2011)

Trouble with overcooling the dryer exhaust is the same as with overcooling chimney flue exhaust. The liquids will condense, you'll get gallons of water in the duct which will weigh it down or leak out onto the floor.


----------



## GunSeth (Mar 24, 2011)

Man, I need to clean my dryer vent.  I also have a extra foot of pipe coiled around the floor that I need to get shorten.  Tonight!


----------



## semipro (Mar 24, 2011)

Highbeam said:
			
		

> Trouble with overcooling the dryer exhaust is the same as with overcooling chimney flue exhaust. The liquids will condense, you'll get gallons of water in the duct which will weigh it down or leak out onto the floor.



It seems you could handle this though by inclining the exhaust and collecting the condensation that runs out one end.  This is commonly done with modern gas central heaters where the condensate is collected near the air handler and drained or pumped elsewhere.  Its also similar to what happens with horizontal bathroom exhaust vents where condensate drains outside during use.


----------



## Slow1 (Mar 25, 2011)

Semipro said:
			
		

> Highbeam said:
> 
> 
> 
> ...



Of course with all the lint I imagine that condensate would be more like mud or sludge and clog a system pretty quickly.  Not saying it can't be done; rather that it would have some unique challenges that probably don't really make the manufacturers eager to jump on the design bandwagon without some external motivation.


----------



## woodgeek (Mar 25, 2011)

I have a conventional dryer but if y'all worry about this heat loss google the offerings for 'condenser dryer'.


----------



## nate379 (Mar 25, 2011)

Huh?  I have an OAK on my stove.  I can barely keep a flame going without it.  Found that out when we had 70-80mph winds and the opening to the OAK got drifted over.



			
				Highbeam said:
			
		

> Seriously Nate, you are in AK and not using an OAK on your BK? Your house must not be as tight as you think. Seems like the farther north you are the more you would benefit from an OAK since every bit of air that your stove blows up the chimney is cold and DRY outside air leaking into your home. Humidity control is a big benefit of OAK.
> 
> I wonder why they haven't put an intake duct on dryers yet. Perhaps this will be the next big thing like when they started adding intake systems for water heaters and furnaces. Has anybody looked on their dryer to see if it is possible to add a duct to the intake?


----------



## semipro (Mar 25, 2011)

woodgeek said:
			
		

> I have a conventional dryer but if y'all worry about this heat loss google the offerings for 'condenser dryer'.



Interesting.  Thanks.  I never knew those existed.  Here's a description I found at this website.  http://ths.gardenweb.com/faq/lists/laundry/2004120958010854.html

"In a condenser dryer, there are two separate "loops". The inside "loop" of air is sealed from the outside environment - air from within the drum is heated, then blown through the tumbling clothes, then the moisture-laden air is passed through a heat exchanger, where the water recondenses. The same dry air is then reheated, where it is again blown through the drum and clothes, and the cycle begins again (this is a more-or-less continuous process).

The outside "loop" in a condenser dryer consists of either air or water. Some condenser dryer models are air-cooled, and use the ambient room air as a heat sink, by blowing it across the outside of the heat exchanger. These dryers will tend to heat the indoor air in one's laundry room significantly. Note however that ONLY heat is released - all MOISTURE is contained within the unit. The condensed water can be either pumped away to a drain line (e.g. into a standpipe shared with the clothes washer) or stored in a container within the dryer to be emptied later (not all models offer both options). All standalone Euro condenser dryers are of this type, i.e. units from Miele, AEG, Bosch, Asko, Malber, and Eurotech."


----------



## semipro (Mar 25, 2011)

A condenser type clothes dryer makes a lot of sense for my application.  I could put it in in the same room (effectively) with my Geospring Heat Pump water heater and use the heat from the drier to heat my domestic hot water.


----------



## joecool85 (Mar 25, 2011)

In doing a little research it appears that condensing dryers use about 15% MORE electricity than a standard dryer.  But since they don't vent any air outside, they obviously save you there.  They also have an up front cost of about twice the price of a regular dryer.  I don't think it would make sense for my application.


----------



## begreen (Mar 25, 2011)

Semipro said:
			
		

> A condenser type clothes dryer makes a lot of sense for my application.  I could put it in in the same room (effectively) with my Geospring Heat Pump water heater and use the heat from the drier to heat my domestic hot water.



Wonder when someone is going to take the cold return flow from a heatpump and use that for refrigeration?


----------



## semipro (Mar 25, 2011)

BeGreen said:
			
		

> Semipro said:
> 
> 
> 
> ...



I'd thought that myself.  Seems like a water heater - fridge combo would work.


----------

