Please explain the 29" dryer thing

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henene4

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Now, I'm not from the US, never been there. Had one real life interaction with US laundry equipment and that was a commercial coin-operated SQ pair in a resort in Cyprus.

So, I read about WPs 29" dryers here and there and in conjunction with another thread I wanted to learn more, but googeling stuff just threw more questions at me.
So I'd be glad if you could enlighten me on the topic of WP dryers. (The whole post is only supposed to cover full size machines, no compacts or such!)

On what I understand:
WP builds dryers in 2 widths: 27" and 29".
Both sizes share some technical simmilaritys and basic operating priciples.
However there are some major internal differences as well.

Now onto my confusion:

First off, aren't the washers 27" wide? Thus, whenever you install them side by side, a 29" dryer does look out of place, or dosen't it? It wouldn't be enough difference to leave a clear optical distinction in my head (my brain wouldn't be abled to clearly identify "wide dryer, slim washer") and thus the setup would look that typical "something is ever so slightly wrong" kind of off off which would drive me insane.

Next thing was why they are 29" wide to begin with.

First I thought capacity. But there are 27" dryers with bigger capacitys then the smallest 29" dryers.

Then I thought about format matching so that TL washer an dryer would have the same depth. Especially on rear control models (which all the 29" dryers are as far as I can tell) a flush fit of the washer panel to the dryer panel and flush fit of the fronts to each other would be important for a good look.
But wouldn't it be far smarter then to basicly create a compromise design which gives both appliance the exact same dimensions? The dryer drum would change a bit and there would be far greater space in the washer cabinet for noise inulation and more sway during spin. And the outsides would look far better symmetry wise when side by side.

Another thought was that as the 29" wide dryers all have top mounted lintfilters, a wider drum means better exposure of the laundry to the air and that the air had more time to catch moisture from the laundry. That would make drying more efficent with the back to back airflow design. Even further, that should make those dryers with thermostaticly controlled sensor dry settings more accurate as well as laundry is more evenly penetrated by heat and thus the temperature readings on the exit side of the drum are closer to the factual average temperature in the drum.

The next big topic I was confused by was the technical differences.

If I gathered informtion correctly, the 27" dryers had 4 rollers as drum suspension while the 29" dryers only had 2 in the back but therefor a felt seal&#92glidebearing on the front.
Why? Don't see any possible reason why one works better with the one type and not the other or vise versa.

Next, WP offers hamper style doors and normal doors. Do these mean anything in terms of width?

In general, which technical differences are there? Different heating power, different motor or blower or even totaly differen drying temperatures? Really no clue there.

And a few last questions about all that:
When was what paired with which width for what reason?
Did Whirlpool have a special scheme as to when a matching dryer was 27" and when it was 29"? Or were there always both width options avaible for pairing?
Also, when did that start?
How did WP dryers develop over time in general? I see some features pop up and disappear, but as far as I can tell the airway and blower design was basicly the same since ever.

I'd really appreciate any input on that to me mystical beast that is WP cooperation dryers, the more knowledge the better.

Thanks for this crash course!
Henrik
 
This should answer some of your questions:

It comes down to capacity:

http://www.warnersstellian.com/dryer-buying-guide/

The wider/larger dryers have greater drum capacity which balances out that of a matching washing machine.

Ages ago when automatic top loaders began displacing wringer and semi-automatics you had what was considered "standard" capacity. Cannot recall exactly when (and am sure others will correct and or add onto), but about the 1960's or so American washing machine manufactures came out with "extra large" capacity top loaders. These larger washers were meant for Madame to get through her wash day faster by doing larger loads. Well bigger washers need larger dryers, so there you are then.

Fast forward to today where top loaders are ditching central beaters and going with impeller plates, they also gain capacity. So you have American *HE* toploaders claiming 4.3 (IIRC) cubic foot capacity. That is quite a lot of wash and will need a larger dryer.

As to the build quality between the two, will leave that to others.

Regarding "why" 27" dryers at all; well besides capacity not all households have room for a 29" dryer. Yes, even those two inches can make a difference, especially when the laundry appliances are being installed in a kitchen or other living area instead of shoved down in basements.

Even more to consider is that dryer makers have found ways to increase capacity while still keeping a 27" width. Suspect as with some front loading washers they simply made the drums a bit deeper. That and or have them take up more space inside cabinet.

The other thing you are probably seeing is that dryers in USA no longer automatically mean those with controls on top/non stackable. To match their front loading washers many dryers sold here today can be stacked. They also have pretty good capacity in order to take the load from the often larger sized washer (think WP Duet and similar machines). Because units are designed to stack (if customer wishes) the dryer must be same width as washer.
[this post was last edited: 11/4/2017-22:28]
 
Larger capacity dryers can hold more, but they take longer to dry, and use more energy since there is a bigger drum to heat up. Maytag SOH dryers have a larger capacity compared to the HOH models, but they can ball up comforters. A Maytag HOH has a smaller capacity, but they can dry a large comforter faster than the SOH dryers.
 
 
Old-style belt-drive washers were 29" so the 29" dryer matched them.

Direct-drive washers were initially 24".  The 27" change on them came about a few years in when capacity was increased, maybe in preparation for discontinuing the belt-drive design?

The 27" platform was introduced in 1996/1997 per the service manual reference, which was before the Calypso match.  Maybe the purpose was to match the 27" washers.

There doesn't seem to be an obvious pattern for 27" or 29" matching of dryers to the 27" washers.  I found it interesting that the dryer match to the Catalyst 27" DD washer is a 29" top-filter dryer.
 
 
Crazy that there's a blatant error at 0:55 -- "no sensing of exhaust temperature" on a timed-dry cycle.  Absolutely there is a thermostat in the exhaust that regulates the heat source.  Another error at 2:03 -- a "thermistor" and "thermostat" perform the same function in regulating the air temperature.
 
The 27 wide dryer is front servicable,whereas the 29 wide dryer needs access to the back for some repairs. Airflow pattern is superior in the 29 wide dryer. Also the wider drum makes it a speedy dryer for wrinkle free results at any temp.
 
Thermostat vs Thermistor

Well, kinda yes, kinda no.

Both sense the temperature of the air.

A thermostat usually refferences a mechanical device like a bi-metalic switch or those pressure-based oldschool thermocouples.
A thermistor however refferences an electronic device which measures temperature by a change in its resistance (most commonly NTC thermistors which have a lower resistance at higher temperature, but there are also PTC thermistors which have a higher resistance at high temps).

A thermostat is usually directly integrated into the circut of the heating device it regulates as it is a physical switch capable of switching high loads. They usually have a fixed temperature at which they switch and can be by nature somewhat slow and inaccurate, especially as they age.
A thermistor has no real switching capability. A control system has to read its resistance value and then react accordingly for examplle by switching a relay. That of course makes the whole setup a little more complicated. However the great advantage is that you get basicly instant readings of verry high accuracy and that one thermistor can cover all temperatures a dryer uses. With bimetalic thermostats, you'd often need one for every operating temperature.

And I think the video wasn't ment to be misleading with the timed dry temperature sensor thing.
What they wanted to bring across was that while the heater of course is cycled to maintain a proper temperature range, there is nothing further going on. Compared to the autodry cycles where these switchings further influence the opertion by turning the timer motor on and off in ever changing intervalls.
 
either machine has 'soft heat' function of some sort.....definitely one of the better drying systems compared to other manufacturers....I favor this machine over my others....

lets talk drying drums, or baffles to be exact.....

the 29", has two baffles, and one speed bump built into the drum....

while as the 27" has three baffles, one being extended more than the other two....

IMHO...I find drop down doors to be easier for loading/unloading versus a side swing door....some like one more than the other...to each his own
 
 
Yes, I understand the difference between a thermistor and a bi-metal thermostat but the point is they do both control the air temperature.  Some models back in the day had a "hydraulic" (or whatever is the proper terminology) continuously variable thermostat like an oven.  TOL models with five pushbuttons temperature selections like the Imperial Mark XII and Mark 18 units did have separate bi-metals for each heat level.
 
Henrik: US laundry areas in homes vary by design. Some have laundry rooms with enough width to accommodate a wider dryer. Some have closet installations which may or may not be wide enough.

My laundry area is in my garage, attached to the house by a door in the kitchen. It doesn't get too cold here (0 C in winter about the lowest) so there is no issue with frozen water lines. Garage laundry areas are popular in single story homes in California (no carrying laundry up or down the stairs), partly because it keeps heat out of the house in summer. Also, because the garage is typically 6 inches/15 cm below the house floor level, any flood from a washer stays in the garage and actually flows toward the street, because there is a slight slant (2 cm or so) to the garage floor, which was done on purpose. It also keeps noise out of the house.

The machines are in an alcove (recessed area in the wall), with the tank water heater to their left, and the furnace to their right. The space was designed for two 27" wide machines sitting side by side. There is no counter since the house was built in 1988, when the FL market in USA was nearly nothing; the space was designed for FLs with rear control panels.

I have an additional issue: there is a government-required bollard (pipe filled with concrete) in front of the washer space, to protect it from being hit by a car (dryer, furnace, water heater are all gas). The bollard is nearly a meter high and would block the door of any FL, even on a pedestal. Some of my neighbors have removed their bollard, but if you sell the house it could fail the required building inspection. My solution was to stack a laundry pair in the dryer space, and leave the bollard alone. I placed a table in the washer space, to hold baskets, etc. (supplies are kept in a cabinet I added above the table).

With my first FL pair, choice was somewhat limited because early FLs like Maytag Neptune could not stack. However, nearly all current FLs here can be stacked. My first set (now working just fine at my neighbor's, 11 1/2 years old with no repairs ever) was Frigidaire 2140 which was 27 wide, 27 deep, 36 high. in a stack, the dryer top was 72 inches above the floor.

My second pair is an Electrolux 60 series pair, purchased three years ago,

http://laundry.reviewed.com/content/electrolux-eifls60ls-washing-machine-review

still 27 inches wide, but 31 inches deep and 38 inches high, so top of the stack is 76 inches high (6 feet 4 inches). I am 180 cm (5'11"), so the dryer drum is perfect height for me, but for someone shorter it might be too high. The point is that Elux "grew" the machine by making it deeper and taller, but they did not make it wider. I think they knew that width is sometimes the controlling parameter for US customers. It is in my case: I have extra room for height and depth, but not for extra width. Some people with inside laundry rooms may have extra width, but sometimes the door (if it swings inward) may not clear wider or deeper machines. It's not really an issue of bad architecture, but rather a reflection on how laundry machines have changed in the 30-40 years since many homes were constructed (the architect did not have a crystal ball to predict the future).

PS as far as I know, Electrolux is the only brand in USA with reversible doors for both washer and dryer. For some customers, door reversibility is the chief reason for buying Electrolux.

PS#2: was an exchange student in Holland (Nimwegen) and there too the garage was attached, and the washing machine was in the garage, so freezing pipes wasn't an issue there. Because this was a family of five kids (with me, six), there were too many bikes and mopeds in the garage for anyone to park a CAR in it, but it was an attached garage.
 
This is the Elux model that replaced the model I have (purchased 2014, 60 series).

http://laundry.reviewed.com/content/electrolux-efls617siw-washing-machine-review

if you scroll to the end, the reviewer states larger machines exist from Kenmore and LG, but if you are trying to keep within a 27 wide space, they recommend Elux.

<span style="font-size: 18pt;">If you absolutely need a larger drum, or if you want a super-fast Normal cycle, we still recommend competitors from Kenmore and LG. But if you just want the cleanest clean for your clothes and need a 27-inch wide washer that will fit in your laundry room, we're confident that you'll love this washing machine, too—especially with its $890 sale price</span>
 
Just gonna tag this onto here

Before creating another thread.

(If you want a quicker read towards the actual matter of this thread-extension, jump the next 2 paragraphs to the huge gap!)

First of all, quick summary: The 29" was just WP standard and basicly simply remained because it was so good, and only has been adapted for a new machine generation.
It's quick, simple and works well, so, everything a dryer needs for the US market.

Quite honestly, this once more makes me belive that US washer makers make most of their revenue via dryer sales.
In the US, buying matched sets even though the old dryer works seems common practice, and given that WP didn't have to redo much in basicly 50 years, and that basic dryer design must have been produced at least 100 Million times, they must have gotten the production cost per unit down to a ridicolus low level.
Here in the EU, dryer purchases are more then 90% seperate purchases, thus, these machines are completly independently priced (well, except for a general price range for a certain line), so a matching dryer can be had a few hundred euros less, sometimes. And they are more often then not basicly totally redesigned to match new efficency goals.

Now what I wanted to know was (in relation to the new SQ coming out, the exploding WP FL and new regulations showing up) actually 3 things (skip the lengthy part if you want a qiker read, there is a compact TL;DR at the verry bottom):

1) Are there any ratings for dryer efficency?
I see some dryers have eco cycles (which either cut drying time or allow for less heating time which works wonders with vented dryers), but as far as I understand drying efficency is calculated into washer efficency. So how does that work? Is a standard dryer used for that determination, or is the matching dryer declared by the manufacturer used?

2) Do you ever recognize huge differences between washer spin speeds and consequent dryer times?

I can see that in several ways.

First of, your market contains both high and low extraction rate washers (in comparison to each other; like 800 vs 1200 rpm). Do you recognize major differences? I mean, your cycle times are way shorter, so a major extration difference should matter more. Did you ever have the option to directly compare something like that?
Here in the EU, ratings are determined for 1000rpm spin speed or a corresponding residual moisture of 60% (so a 10lbs dry load would weigh 16lbs wet for testing). Our most sold spin speed is 1400rpm however, which boils down to 50% residual moisture. Our "high" spin speed standard is 1600rpm which cuts that down to 44%.
That latter one yields savings of something like 25% time and energy, but that is under higly standardized high load conditions. In real life though, you sually only have the 1400rpm vs 1600 rpm situation, and that gives you results one could onyl notic ine extreme cases or as a hunch otherwise.

So, would you vague to say that washer spin speeds make a noticeable difference for the same dryer being used?

The other side of this is the idea of optimizig dryers for one scenario. You see, it's been mentioned that SQ dryers run particulary hot and as most SQ dryers are paired with lower spin TLs, it would make sense to make the dryer run hotter to compensate for the lower spin speed. For the average consumer, cycle times would stay about equal.
Dryers paired with high spin washer however usually appear to run basicly the same time (about an hour for an average load of towels) as a low spin paired dryer would.

So have you noticed a tendency of the dryers working better with washers from the same "world", so to speak? Like that as SQ dryer would run far to hot for a WP FL, or that a WP dryer that would be paired with a FL would take longer for a load spun far lower?

3) Do you think there should be a seperate dryer rating label?

I know most will scream in anger at that idea, but hear me out.

Right now, your washer ratings include the enegry used to dry the laundry afterwards. That's included in the integrated modified energy factor (I think that is what it is called). Move that out and therefor include an extraction efficency rating sperately, reasoning that you might use a dryer that is not refferenced to the washers energy label. That would make the label more accurate overall thus allowing for more slack in energy usage.
Further, manufacturers wouldn't be tempted to try to adapt washers to compensate for inefficent dryers as that (especially looking at WP) might be more cost efficent in terms of development.

The bigger effect however would be the incentive to actually improve dryers in a way that actually does something.
If a stand alone dryer is rated poorly, that has a far greater impact visually then if there is just one mediocre rating.
Further, even if we are just talking about vented dryers, there are so many ways these could be made more efficent.
The EU label includes a rating (condensation efficency) to actually make people abled to compare how "air tight" a dryer system is. Add that. In the US, dryers often are forced to use up airconditioned air. That would then be heated up and exhausted out. If that air leaks into the room, it would actually be less efficent in regards to HVAC than if it was vented. Your HVAC most likely won't suck the ~150F air back in once its been vented by the dryer, but if it ends up in the room, it has to handle that rather rather then the ~100F outside air.
Vented dryers could probably recapture heat from the ventig air pretty simply. Just design a small section of the airpath towards the heater to shape around the vent path. If its small enough, the will close to no condensation or if its big enough, a condensation drain might make sense for the mode given.
And, last but not least, actually smart heat management. Especially a vented dryer can dry in a verry wide range of temperatures verry efficently. There even was an "A" rated vented dryer over here that took that ability to the extreme: It's label cycle lasted 7-8 hours, but it simply never activated the heater. The motor used only 200W an hour, so it used less then 2kW for 6kg of laundry. Your driers don't have to do that that extremly, but especially towards the end, a dryer probably could shave of 10-20% of energy usage by just tmpering the heat well and shutting it of at just the point at which the residual heat in the load is enought to drive out the last bit of moisture.
Of course, that might also finally make the way open for the heat pump dryer the US needs to be convinced.

Fun fact, actually: I had a power share concept for a US washer/dryer setup in my head for quite some time.
A heat pump dryer to run at US speeds would need a 2kW heatpump, propbably. Thus it would have to run on 240V.
But one could be sneaky. The main machine part of dryer (so motor, heatpump, electronics) could run off of one 120V leg maxing that out at 15 to 20 amps.
The washers main components would run off of a normal 120V plug as usual.
Now, one would run one connection wire on a propiertery cable between washer and dryer.
Both the washer and dryer would have a 120V heater build in. In the dryer, that would be used simmilar to the HybridCare system WP has, and on the washer, that would be a supplement booster heater for super quick super hot washes.
Both washer and dryer would have a small communication board with a relay for that source on it.
Now, whenever either machine could benefit from boosted heating power, these communication boards would handshake via a data connection integrated into the propiertery cable. Then, they could give either machine access to that unused 120V leg, but only one at a time.
See the benefit? Both your dryer and washer could have a maximum power budget of beyond 3kW with only one 24OV outlet.

TL;DR:

1) Are there any ratings for dryer efficency?
2) Do you ever recognize huge differences between washer spin speeds and consequent dryer times (both for paired sets an especially for non matched washers and dryers of completly different styles)?
3) Do you think there should be a seperate dryer rating label?
 
With all the hoopla about washer water-energy use-NO ONE has addressed energy use of dryers-far MORE power used by them than even the least efficient washer!Yet EVERYONE uses a dryer these days.They are convenient-so folks will use them.
 
Dryer Efficiency

I agree with 'tolivac'--people go on and on about washers but ignore the dryer side. Though I've never had one, have always heard that gas dryers are much more energy-efficient than electric ones. I know that gas refrigerators are both more energy-efficient but also more reliable. I can remember that when we tore down an old hospital in Houston after building a new one, there were refrigerators there, a bunch of them, that were well over a half-century old and still running fine.

Of course, if other people's refrigerators are like mine, it's always the damned ice maker that goes out first...
 
Why do people keeping going on about air conditoning

And dryers? As if the thing is on 24/7 365 days of the year?

That might be true in some parts of the USA but not certainly in our neck of the woods. In fact try to minimize AC where possible in all but the most hot and or humid weather because don't like "stale" air. Cold nor warm....

In many parts of the USA dryers/laundry areas are located in garages, back porches, car ports, basements and or other areas that aren't air conditioned. At my parent's home the laundry is in cellar, which is not heated. Well the boilers are down there so guess to an extent it is, but not directly on purpose.
 

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