Freezer freezin' my toes!
June 27, 2012 11:40 AM Subscribe
Is there a sensible reason that freezer drawers on the bottom aren't made out of a solid piece of plastic to keep the cold air in?
So I recently moved into a new apartment, and this one has the fridge/freezer with the freezer on the bottom, which I like a lot since the more commonly accessed fridge part is more convenient this way. However, I was quite surprised when I opened up the freezer drawer to see that it was a metal cage, so you can basically see straight through to the floor when the drawer is open!
What the hell? Why on earth wouldn't they make it a solid plastic piece so you can keep the cold air in to make it more efficient? Like the old dedicated freezer chest thing my parents had in the basement? On those you could open up the top, look around for as long as you liked, grab whatever you wanted, and all the cold air generally stayed put. But whenever I grab something from my freezer now, the second I open it, out comes all the cold air in there and chills my poor little toes.
I was also surprised to see that it's not just the GE brand freezer in my apartment that has this, other brands seem to be similar.
So my question is this: Are the designers of these things absolutely clueless about thermodynamics? Or is there some reasonable explanation for why they don't design them with sensible bottoms?
Bonus question: Is there a handy way to seal up the cages so that I can make my freezer less drafty when I open it?
So I recently moved into a new apartment, and this one has the fridge/freezer with the freezer on the bottom, which I like a lot since the more commonly accessed fridge part is more convenient this way. However, I was quite surprised when I opened up the freezer drawer to see that it was a metal cage, so you can basically see straight through to the floor when the drawer is open!
What the hell? Why on earth wouldn't they make it a solid plastic piece so you can keep the cold air in to make it more efficient? Like the old dedicated freezer chest thing my parents had in the basement? On those you could open up the top, look around for as long as you liked, grab whatever you wanted, and all the cold air generally stayed put. But whenever I grab something from my freezer now, the second I open it, out comes all the cold air in there and chills my poor little toes.
I was also surprised to see that it's not just the GE brand freezer in my apartment that has this, other brands seem to be similar.
So my question is this: Are the designers of these things absolutely clueless about thermodynamics? Or is there some reasonable explanation for why they don't design them with sensible bottoms?
Bonus question: Is there a handy way to seal up the cages so that I can make my freezer less drafty when I open it?
As I understand it, the drawers are open to allow airflow when things aren't packed totally in the freezer. The airflow from the freezer may help maintain the temperature in the fridge part of the unit as well (it does in my side by side).
I used to have freezing/melting problems with my GE side by side until I turned the temperatures for the freezer and the fridge to "medium" for each (medium freeze, medium cool) and fixed my freezer to allow airflow. On my side by side, the airflow is up through the back of the freezer - I was cramming things as far back as they could go, restricting airflow. I put stoppers on the shelves in back to prevent that and maintain airflow.
I also expect that, given the surface area of a bottom freezer, a large plastic bin would be more likely to crack from being shoved around with the weight it holds relative to the surface area of the drawer and thickness of the plastic. I've broken narrow fridge drawers through rough treatment.
One resource I found for whys of refrigeration and freezing is fixya.com.
posted by tilde at 11:45 AM on June 27, 2012
I used to have freezing/melting problems with my GE side by side until I turned the temperatures for the freezer and the fridge to "medium" for each (medium freeze, medium cool) and fixed my freezer to allow airflow. On my side by side, the airflow is up through the back of the freezer - I was cramming things as far back as they could go, restricting airflow. I put stoppers on the shelves in back to prevent that and maintain airflow.
I also expect that, given the surface area of a bottom freezer, a large plastic bin would be more likely to crack from being shoved around with the weight it holds relative to the surface area of the drawer and thickness of the plastic. I've broken narrow fridge drawers through rough treatment.
One resource I found for whys of refrigeration and freezing is fixya.com.
posted by tilde at 11:45 AM on June 27, 2012
Bonus question: Is there a handy way to seal up the cages so that I can make my freezer less drafty when I open it?
Duct tape! (or a piece of corrugated plastic cut to size)
posted by zephyr_words at 11:46 AM on June 27, 2012
Duct tape! (or a piece of corrugated plastic cut to size)
posted by zephyr_words at 11:46 AM on June 27, 2012
You want the cold air to circulate around the food. The air is relatively easy to cool, so its loss isn't going to diminish cooling.
But more to the point - the air isn't still when you open the door and the motion of the doors coming in and going out will have a much bigger effect of air transfer than simple sinking of cold air.
Put a sheet of aluminum foil in the bottom of the cage and you'll see that the air still goes around the drawer.
posted by bensherman at 11:47 AM on June 27, 2012
But more to the point - the air isn't still when you open the door and the motion of the doors coming in and going out will have a much bigger effect of air transfer than simple sinking of cold air.
Put a sheet of aluminum foil in the bottom of the cage and you'll see that the air still goes around the drawer.
posted by bensherman at 11:47 AM on June 27, 2012
Best answer: Airflow in the freezer when it's closed is very important -- not only for keeping every part of the freezer at the same temperature but also to help cool the fridge. Air really needs to be able to move freely around the (closed) freezer. A solid drawer would impede this. The ones with the lid on top can have air circulate freely because there aren't barriers between parts of the freezer, like you're asking about.
posted by brainmouse at 11:48 AM on June 27, 2012 [2 favorites]
posted by brainmouse at 11:48 AM on June 27, 2012 [2 favorites]
Do you mean you can see to the floor of the fridge or the floor of your apartment beneath the fridge? The former seems reasonable, the latter, insane.
posted by elizardbits at 11:49 AM on June 27, 2012 [2 favorites]
posted by elizardbits at 11:49 AM on June 27, 2012 [2 favorites]
(He means that when he opens the drawer of the freezer, it's see-through to the floor -- when the freezer drawer is closed, it's contained entirely within its freezer-box. This is indeed pretty standard)
posted by brainmouse at 12:00 PM on June 27, 2012
posted by brainmouse at 12:00 PM on June 27, 2012
It's the latter. My parents' fridges are just like this. The freezer on the bottom is a big drawer, rather than a swinging door. The "box" of the drawer is a wire basket, so if you pull it out while empty you'll see right through it to the floor. Imagine your silverware drawer were a wire basket rather than a wooden box. When you pulled it out, you'd see the floor through it. Same arrangement.
I think the basic reason for this is two-fold. That drawer, were it made of solid metal, would be prohibitively heavy. If made of solid plastic, it would probably be far too brittle. Imagine a plastic drawer, loaded with frozen food, cantilevered out a couple feet. That'll be a lot of stress on that plastic drawer.
Aside from those considerations, a solid drawer won't do what you want. I think you'll find that, even if you seal up that metal basket with foil or somesuch, that when you pull out the drawer you'll still feel the rush of cold air because the space around the drawer is full of cold air which will flow out of the freezer when you open it. The freezer is not implemented as a "drawer full of cold air" as much as it is a box full of cold air that has a drawer suspended in it.
posted by chazlarson at 12:04 PM on June 27, 2012 [1 favorite]
I think the basic reason for this is two-fold. That drawer, were it made of solid metal, would be prohibitively heavy. If made of solid plastic, it would probably be far too brittle. Imagine a plastic drawer, loaded with frozen food, cantilevered out a couple feet. That'll be a lot of stress on that plastic drawer.
Aside from those considerations, a solid drawer won't do what you want. I think you'll find that, even if you seal up that metal basket with foil or somesuch, that when you pull out the drawer you'll still feel the rush of cold air because the space around the drawer is full of cold air which will flow out of the freezer when you open it. The freezer is not implemented as a "drawer full of cold air" as much as it is a box full of cold air that has a drawer suspended in it.
posted by chazlarson at 12:04 PM on June 27, 2012 [1 favorite]
The job of that drawer isn't to keep cold air in. It's to let warm air out, when you put something in it which is at room temperature.
Something new in the porous drawer will freeze faster than if the drawer was solid, because there's better air flow of cold air over it, and better flow of warm air escaping from it.
posted by Chocolate Pickle at 12:05 PM on June 27, 2012 [3 favorites]
Something new in the porous drawer will freeze faster than if the drawer was solid, because there's better air flow of cold air over it, and better flow of warm air escaping from it.
posted by Chocolate Pickle at 12:05 PM on June 27, 2012 [3 favorites]
Condensation. The bottom would get gunked up with ice and freeze your forgottens to its base. Wire grids don't do that
posted by MangyCarface at 12:15 PM on June 27, 2012 [1 favorite]
posted by MangyCarface at 12:15 PM on June 27, 2012 [1 favorite]
I've seen refrigerators that had a solid plastic drawer for a freezer on the bottom--in fact, I didn't know there was another kind. Even in the store display models, the bottom was full of dust and hair. I ixnayed freezer-on-bottom models just for that reason.
posted by darksasami at 12:22 PM on June 27, 2012
posted by darksasami at 12:22 PM on June 27, 2012
The freezer on the bottom is a big drawer, rather than a swinging door. The "box" of the drawer is a wire basket, so if you pull it out while empty you'll see right through it to the floor.
You know what? I totally misread this question. Wire drawers are totally normal; I thought the actual fridge didn't have a bottom, so that you saw through to the floor with the drawer closed. My apologies!
posted by DarlingBri at 12:23 PM on June 27, 2012
You know what? I totally misread this question. Wire drawers are totally normal; I thought the actual fridge didn't have a bottom, so that you saw through to the floor with the drawer closed. My apologies!
posted by DarlingBri at 12:23 PM on June 27, 2012
The freezer is designed to be most efficient when the drawer is closed, because it is closed the majority of the time.
posted by SuperSquirrel at 12:50 PM on June 27, 2012 [1 favorite]
posted by SuperSquirrel at 12:50 PM on June 27, 2012 [1 favorite]
The coils that make the freezer cold are surrounding the drawer, not part of the drawer. If the drawer were solid it would insulate the food from the coils, which would make the freezer less efficient.
posted by bondcliff at 1:11 PM on June 27, 2012
posted by bondcliff at 1:11 PM on June 27, 2012
My first reaction is always to assume "because it's cheaper that way."
It may have to do with defrosting... so you can just open it and let everything drain onto something you had the foresight to put on your floor. I dunno.
It's annoying though. Someone didn't quite close mine once and a bunch of fruit juice popsicles my wife had made melted, dripped all over the floor under and in front of the fridge and then dried before anyone got home. Man, that was awesome to clean up.
posted by jeffamaphone at 1:24 PM on June 27, 2012
It may have to do with defrosting... so you can just open it and let everything drain onto something you had the foresight to put on your floor. I dunno.
It's annoying though. Someone didn't quite close mine once and a bunch of fruit juice popsicles my wife had made melted, dripped all over the floor under and in front of the fridge and then dried before anyone got home. Man, that was awesome to clean up.
posted by jeffamaphone at 1:24 PM on June 27, 2012
It's for air circulation and so that a leak in the fridge doesn't fill up the basket with water giving you a basket sized Ice Cube.
posted by Mitheral at 1:39 PM on June 27, 2012 [1 favorite]
posted by Mitheral at 1:39 PM on June 27, 2012 [1 favorite]
(For anyone who is as momentarily baffled as I was, I assume this is what we're talking about.)
posted by DarlingBri at 1:50 PM on June 27, 2012
posted by DarlingBri at 1:50 PM on June 27, 2012
Best answer: Yes, a chest freezer accessible from the top will waste a little less energy than one with a door on the front. But only a very little. The most important thing for freezer efficiency is how good the insulation is with the door closed, and unless you're in the habit of leaving it open for minutes at a time, cold air spillage during access really doesn't matter much.
The amount of energy required to cool things is, to a first approximation, proportional to their mass. The mass of the air inside your freezer compartment is negligible compared to the mass of the frozen goods, so whether you drop out all the air in the freezer or only part of it when you open the freezer door, the air inside the compartment will drop very quickly to below freezing temperature when the door is closed again and it doesn't take much energy to make that happen.
Still air is a good thermal insulator; moving air is good at transferring heat via convection. When you put things into the freezer drawer, you want a convective air flow around them to transfer their heat quickly into the freezer walls for removal. Blocking that airflow for the sake of minimizing heat gain with the door open is therefore optimizing the wrong thing.
Provided the door seals are in good condition and you're not feeling cold air on your toes with the door closed, you're good.
posted by flabdablet at 4:54 PM on June 27, 2012 [1 favorite]
The amount of energy required to cool things is, to a first approximation, proportional to their mass. The mass of the air inside your freezer compartment is negligible compared to the mass of the frozen goods, so whether you drop out all the air in the freezer or only part of it when you open the freezer door, the air inside the compartment will drop very quickly to below freezing temperature when the door is closed again and it doesn't take much energy to make that happen.
Still air is a good thermal insulator; moving air is good at transferring heat via convection. When you put things into the freezer drawer, you want a convective air flow around them to transfer their heat quickly into the freezer walls for removal. Blocking that airflow for the sake of minimizing heat gain with the door open is therefore optimizing the wrong thing.
Provided the door seals are in good condition and you're not feeling cold air on your toes with the door closed, you're good.
posted by flabdablet at 4:54 PM on June 27, 2012 [1 favorite]
Best answer: Why on earth wouldn't they make it a solid plastic piece so you can keep the cold air in to make it more efficient?
The simple reason is that keeping the cold air inside contributes very little to efficiency because the heat capacity of air is so small. The amount of heat removed to cool a quart of air is 4000 times less than the heat removed to cool a quart of water. In other words, when a quart of cool air escapes, it takes relatively little effort to cool the warm air that replaces it. You just aren't losing that much when the cold air leaks out because air doesn't hold much heat.
Given that escaping air is of little consequence, the next most important considerations are as explained by others above -- the wire basket allows air to circulate so new food placed in the basket freezes more quickly and the wire basket is much lighter than a solid basket.
posted by JackFlash at 5:31 PM on June 27, 2012
The simple reason is that keeping the cold air inside contributes very little to efficiency because the heat capacity of air is so small. The amount of heat removed to cool a quart of air is 4000 times less than the heat removed to cool a quart of water. In other words, when a quart of cool air escapes, it takes relatively little effort to cool the warm air that replaces it. You just aren't losing that much when the cold air leaks out because air doesn't hold much heat.
Given that escaping air is of little consequence, the next most important considerations are as explained by others above -- the wire basket allows air to circulate so new food placed in the basket freezes more quickly and the wire basket is much lighter than a solid basket.
posted by JackFlash at 5:31 PM on June 27, 2012
I assume this is what we're talking about.
OH OKAY. That is way less crazy than what I was picturing, which was that the entire bottom of the fridge when the drawer was CLOSED was open to the floor beneath it.
posted by elizardbits at 5:50 PM on June 27, 2012
OH OKAY. That is way less crazy than what I was picturing, which was that the entire bottom of the fridge when the drawer was CLOSED was open to the floor beneath it.
posted by elizardbits at 5:50 PM on June 27, 2012
ME TOO, and that was indeed... crazy!
posted by DarlingBri at 6:57 PM on June 27, 2012
posted by DarlingBri at 6:57 PM on June 27, 2012
This thread is closed to new comments.
posted by DarlingBri at 11:42 AM on June 27, 2012 [1 favorite]