Modern Refrigerator

[urarachu]

A woman came into the shop today, complaining about how her vacuum, car, and refrigerator were all having problems in the same week. I laughed and asked her what exactly was wrong with the fridge. She said it was cracking all over. Where the shelves sat it was cracking. She said it was a Kenmore. Apparently they get many calls a day about cracking fridges...

I was appalled. I guess I never thought about refrigerators having such awful problems. I guess all appliances are being equally cheapened these days...

*sigh*

 

[appnut]

And I am thinking about replacing my 26 y/o Kenmore???.....

 

[maytagbear]

Bob,

if your refrigerator is running well, why the heck replace it?

Lawrence/Maytagbear

 

[DADoES]

Long-term energy cost... ?

 

[appnut]

Glenn, that's what's pushing the consideration into my mind.

 

[maytagbear]

well, then,

good luck, Bob. I hope you find one that isn't total crap.

Lawrence/Maytagbear

 

[kenwashesmonday]

Why not replace your 26 year old Kenmore with a nice 50 year old natural draft 2-door refrigerator. It would be a step up in quality and energy efficiency.

Ken D.

 

[scott55405]

What is a natural draft 2 door refrigerator?

In all events, if this Kenmore in question is a Whirlpool product, I do know there were issues with interior liners and such on some of certain more recent vintage that the company has been aware of.

 

[kenwashesmonday]

A non frost free fridge (no fans inside, not defrost timer, no defrost heater) with totaly seperate freezer compartment.

Ken

 

[dalangdon]

Bob, we've been very happy with our Frigidaire side-by-side that we got on clearance at Lowes. There was a major problem at first that caused some real drama (they hadn't hooked up the defroster, and ice built up inside which shut the thing that refrigerates the refrigerator off) but they fixed that free of charge.

"This year's Model" is even more glam. The light comes up on a dimmer when you open it, which is pretty nifty. I'm a sucker for stuff like that

 

[irishwashguy]

My 60's Coldspot is the best frindge i have ever had....

Energy,smenergy!!! The man where I bought my vintage fridge helped me to understand why some of the new ones are crap.He had a bunch of them in the back of his store that he was retro fitting with defrost timers and throwing the eletronics in the trash. Mind you they were the cheap apartment grade G.E.'s that were cheap in the first place. He said that they did not have problems after that. Low tec is better in many cases.

 

[Designgeek]

I'm just starting an R&D project on high-efficiency fridges & freezers. Goal is to get total power consumption down below 175 KWH/year.

A good modern fridge typically uses 600, old energy-hogs use @ 1,000 and up, and current best-practice commercial models use about 350. The best available is Sun Frost, at 110 KWH/year but a cost of $2,500. We expect to come in at about half the cost of SunFrost.

Once I get the design finalized, we're going to see about starting a company to produce & sell these. Yes, seriously. More news when there's news...

 

[thor]

What size?

Power consumption depends on the fridge size. What would be the size you are aiming at?

 

[rp2813]

Hey Appnut, I gotta say I really like the KitchenAid side-by-side I bought a couple of years ago, and am hoping that since it's made by Whirlpool that I don't encounter any cracking problems. So far so good.

Besides wanting a good frig that would last me a while, I also wanted convenience in ice access. The model I bought has the ice bin in the top of the freezer door. No more flipping the bin door open and blindly reaching in to get ice when I'm wanting to take it out large quantities. I can even punch a button and release the ice bin from the freezer door and set it on the counter. My favorite thing about it is that the entire ice making operation is controlled by an electric eye. No more wire arm to raise up and down to turn it on or off. That arm system wouldn't work with the bin in the door so they came up with the electric eye. I hope it doesn't cause problems down the road. I also like the fact that I can change out the water filter without having to shut off the water supply.

My only complaint is that you have to really shove the crisper drawer closed. It has some kind of seal that requires it to snap shut. I've gotten used to it, but would prefer it if it glided to a close as easily as the deli and meat drawers do.

 

[Cybrvanr]

Actually, power consumption does NOT depend on fridge size, especially on the newer ones that are highly insulated. Now, there's probably a significant difference in say, a dorm fridge, and a huge sub-zero, but I noticed there's not much diff between that dorm fridge, and a 12 cu/ft fridge.

Refrigerators made in the seventies and a little bit before and after seem to be the worst energy hogs. They had small amounts of insulation in them, and compensated by using fans, which consume energy in their own right. Prior to this era, most refrigerators had natural-draft rear condensers. During this "energy hog" era, most manufacturers went to bottom condensers. This is a double whammy. Not only do they radiate their heat back into the food compartment, but they also nee a fan to move air over them. Inside, the manufacturers hid the coils behind panels, and used fans to move air over them.

Although modern refrigerators are better with energy than some of their older predecessors, they are still have some design flaws that keep them from being as good of performers as they could be. We've taken one step forward, but two steps back.

Some of the non-popular brands like sunfrost and Equator go back to natural draft like Ken describes, and was the defacto standard in the 50's and before. I believe Fridigaire held onto natural draft condensers well into the early 70's, although some of their interior evaporators had draft fans.

 

[Designgeek]

Thor- 8 to 9 cubic feet total, of which about 5 - 6 would be refrigeration, and 3 to 4 would be freezer. The smaller size could also be configured as a fridge, so 3 - 4 cuic feet each.

Though, I agree that power consumption does not increase linearly with size. Near as I can tell, if it were plotted on a curve it would be similar to an inverse exponential, i.e. it would flatten out toward the right side of the graph.

Now here are a couple of candidates for dumb questions

What are the relevant characteristics of a crisper, and of other special sections in a fridge? That is, is it only temp and humidity, or is it also something to do with air circulation?

What are good foods to test those features with, in what quantities or weights, and how long should they keep fresh in the correct compartments?

As it stands, we're going to be measuring temperatures at two or three points simultaneously in each cabinet for test purposes, so what sort of variations should we be looking for?

 

[thor]

While working as the production manager at a local refrigerator plant, the same company had a huge engineering sector in another facility, where there was a room they called "the calorimeter". This room actually was a heavily insulated room with a door similar to a freezing chamber, that could maintain a steady room temperature of 32 °C or 43 °C, to test N (normal) or T (Tropical) class refrigerators respectively.

Although I saw this test carried out many times in different units, I was never in charge of the procedures. These people followed a very precise test procedure, which measured the temperatures of the different parts of the unit, e.g., hot gas discharge, hot liquid after condenser, cold gas return line, freezer and different sectors of the refrigerator, etc.

One thing I remeber quite clearly is that they had these blocks of some product like a jelly, which would be placed in different parts of the freezer and the refrigerator sections. Then, they would place some of the temperature probes inside this packages.

The whole procedure took something like two or three days to carry out. I still have the chance to call some of these technicians, and I could definitily ask them for a copy of this procedure.

 

[kenwashesmonday]

Here are some pictures of nice energy efficient refrigerator.
(not my page)
Mine is a bit older than this and doesn't have the lazy-susan shelves.
The freezer is a little small by todays standards, but it stays right around 0 degrees f. No defrost cycle to make your ice cream gummy. No fans to dry out food or spread food odors to the freezer.
Note the butter hardness control on the door, tough to live without one once you've had one.

I defrost the freezer only once a year, and it's humid here in northern NJ. That's a sign of good insulation.

Ken

http://www.whiteboard.net/~luke/refrigerator/

 

[Designgeek]

Ken, very cool GE fridge there (ha). The lazy susan shelves are clever, probably make the unit easier to clean in back, and of course easier to access all the food. Was there actually a separate cooling system in the butter & cheese compartment? How did that work?

I'd like to know more about your observation re. defrost cycles causing ice cream to get gummy. IMHO, gummy ice cream is gross; I prefer my ice cream "frosty" like compacted snow rather than "elastic" and gummy. Can you tell me more about the comparison between frost-free vs. manually-defrosted freezers in terms of impact on ice cream (and other foods)?

Thor, I'm very interested to know anything you can find out about the test procedures at your plant. In particular I'd like to know what those jelly-like cubes were made of and exactly how large they were (length x width x depth), and how they were arranged inside the fridges for testing.

The test procedure I'm planning to use so far, is to put temperature probes in various places inside each unit, and use some number of gallon jugs of water as standardized "load." Though, water is a very "dense" material for this, and I'm going to need other "lighter" materials as well. We're going to be measuring ambient room temperature, and temperature of air adjacent to the warm output side of the cooling system, just to have these data in case they provide other useful information (e.g. effect of distance between units and walls, effect of room temperature on power consumption, etc.).

We can't build a temperature-controlled room for this but we can and will heat the room as needed to maintain a fairly constant temperature and to examine the effect of changes in room temperature on power consumption to maintain a given inside-cabinet temperature.

Our temp probes and power meters should be coming in today or at latest Monday. Can't wait to roll up my sleeves and get going on this...