Why aren't refrigerators & freezers designed to benefit from outside cold air?

[micky]

JB is right, if you vent air out of the house, it will have to be replaced by other air, warm air from outside the house. If you used the same air, sucked in air from outside just to cool the coils, it would not cool the coils as well, because it woudl be hotter than the air iln the rest of your house** So you'd need more air, that is a faster fan.

** (My house at least is much cooler than outside on the first floor. Tnat's not always true on the seocnd floor)

You'd have to have the coils that are on the back of the fridge outside the house instead.

When I had AC, I only used it 20 or 30 days a year, in Baltimore, but even when I wasn't using it, I never noticed heat coming from the fridge. Now that my AC is broken for the last 2 years or so, I still don't noticed any heat. Admittedly, the coils are in the back and the heat from them gradually spreads into the rest of the kitchen, but I think what really makes the difference is that I don't open the fridge door very much. If the door isn't opened, like for 8 hours every night, I'll bet the thing hardly runs at all.

Again, there's only one of me, but otoh some people just open the door and stare at the food for a while.

[bob haller]

ahh, another old thread, this one is from 2010.

lets hope the same google groups IT techs arent put in charge of google self driving vehicles:(

[Stormin Mormon]

we have A/C. my house doesn't. I live in Oregon. the few weeks when it gets very hot the refrigerator feels like the range has been left on. simply venting this hot air out thru the roof or exterior wall doesn't seem too difficult. I could add a bathroom vent fan if needed and have it turn on when the refr runs. all of this is a comfort issue, not $ savings.

Doing the outside air thing makes sense. But it would need coordination between the builders, the HVAC folks, and the refrigerator designers.

BTW, the coils which get hot are condenser coils, the cold ones are evaporator. If you put the evaporator coils outdoors, the food would be warm.

[bob haller]

one could probably have a heat echanger outside, run pex to the kitchen attach somehow the condensor coils to say copper line then pump the water of antifreeze from outside thru the coils attached to the fridges heat exchanger.

its a interesting thought

[trader_4]

It doesn't make sense. The heat generated by a modern refrigerator is minimal. In winter, it adds to the heat you want in the house. Spring/Fall, you typically have windows open, so it doesn't matter. In summer, if you have no AC, you typically have the windows open, so it isn't going to matter much. If you have AC it's a small negative impact on the energy balance. A refrigerator costs less that $100 a year to run. That isn't much heat. Now compare that to the cost of the venting, the problems with running the venting, connecting the venting somehow to the fridge, the electric used to power the venting, etc and it doesn't add up.

[Mayayana]

I'd suggest you get a real newsreader and stop using Google's abomination. You've responded to a 5-year-old post. By now the poster has no doubt invented the refrigerator he dreamed of.

[Stormin Mormon]

When it gets below 30F in New York, I wonder why we run our refrig in the 70 degree indoors. Seems like it would make sense to duct in the cold outdoor air.

[trader_4]

Not when the cost to run a fridge is under $100 a year. Clearly that isn't a lot of heat. And the heat is only an issue in the summer, with AC on. In winter, it's helping. What do you think all that, ie fluid pumps, antifreeze, piping, another heat exchanger, etc would add in terms of cost, maintenance, failure points, etc? Why fix what's not broken?

[trader_4]

Because the heat is helping heat your house for one thing. It costs less than $100 a year to run a fridge. Let's say it amounts to $30 in winter. It's like getting $30 worth of electric heat added to the house. And I can almost assure you that once you start making more holes going outside, ducting in cold air, you're going to wind up losing plenty of energy too. Leaks around openings, ducts that fail, come apart. Why fix what isn't broken? Even if you had a fridge where it was possible to install it that way, you'd find out that 99.X% would never use it.

[trader_4]

Here we go again. Try using Google Groups for once, instead of blindly complaining about it. The date of every post is clearly shown. People do Google searches for a particular problem, find old threads and proceed to respond to them. What would you prefer, that all old threads and the information be lost forever, so it's *all* started over again, each time?

[jloveski]

I know this is a bit late to reply to this one, but the answer is simple: " It's because the destructive, unsustainable energy we consume is ridiculous ly & artificially cheap". This is because not only are the many, destructiv e, externalizer costs (think oil wars & spills, nuclear waste disposal, air & water pollution, climate change, etc) of this energy not figured into th e price, but these energies are all subsidized by our backwards gov. polici es. That's right, they take "our" hard earned money (to the tune of 800 bil lion + globally per annum), and give it to oil companies alone. If instead of paying the taxes we pay regardless, we only paid more for the energy we used.., and only when we used it, then we'd demand more efficient appliance s, homes, cars, etc. Now add to that if our gov. rightly incorporated into fuel costs the "true" cost of every oil spill (not there worthless attempts to "remediate" them, but actually paid for the damage done to the ecosyste m, economies, etc.), the costs of every oil war (trillions?!), the costs of all the air pollution (think hospitalization, premature deaths, etc)... Nu clear catastrophes and hazardous waste dumping (see Hanford nuclear waste s ite for but one example) then and ONLY then would appliances,,homes, vehicl es etc. be made as efficiently as possible. So there you have it... The "t ruth" as to why these seemingly common sense efficiency improvements don't enter the market... Because our unsustainable energy is "ARTIFICIALLY" chea p! Fur anyone reading this post, do your part to help solve this crisis of idiocy and write, call or at least email your representatives and let them know that you demand that unsustainable energy sources are taxed to incorp orate their "true" costs. Don't worry, your energy bills will not increase because viable, sustainable energy sources and efficient technologies will take over more quickly than you can possibly imagine. Here's to a just and peaceful future based on logic and sanity.

[Stormin Mormon]

the answer is simple: "It's because the destructive, unsustainable energy we consume is ridiculously & artificially cheap".

The setup costs of the ducting, and the sensors would outweigh the energy saving. Now, what were you saying?

[gfretwell]

I guess you didn't study thermodynamics in school. In the winter, the fridge is a heat pump, assisting your furnace in keeping your house warm. It takes the heat from things you put in there and returns it to the house. At that point the only "waste" is from the time that you have the door open. If you heat exchanged it with cooler outside air, you are throwing that heat away. The only time it really hurts you is in the summer when you are paying for air conditioning but that is true of everything electrical and any fossil fuel appliances you have, minus what goes up the flue, particularly if you do not have fresh air for combustion.

I am in Florida and my water heater is outside the HVAC envelope, just for that reason. I also cook outside as much as possible.

[todd3620]

Interesting topic. Probably the benefit doesn't outweigh the cost. Or mayb it is a wash. When I go to the grocery store, I see plenty of free-standing refrigerated cases that put warm air into the space, which then must be re moved by the a/c for the whole store. Then again, the big cases are all coo led from outside. My own home refer warms my house in the winter, but goes against the a/c in the summer, so it is a wash.

[trader_4]

Of course hippies don't study thermodynamics or much other science for that matter. They just smoke pot, hug trees and have beliefs.

[ty.marbut]

I know you were talking about this years ago, but I just wanted to write in that I moved into a house that has a wine cellar. The problem is that the last owners were probably paying hundreds, if under a thousand, dollars pe r year to keep it cool. But in Montana, we have lots of cools - even on th e hottest day of the year, it's likely to drop below 50F at night.

So, I ran some ductwork into and out of the wine cellar from outdoors, stuc k some 43CFM CPU fans in it (2 on input, 2 on output), and turned it on ove rnight.

Problems on first try: 3" duct is too small, even with power. More import antly, corrugated flexible duct is extremely resistive to air flow. And it 's also apparently a great conductor. The duct traverses the ceiling of th e wood room (firewood storage, so not generally heated), and comes out the other end of the tube at whatever temperature it is in the wood room.

Results: Pumping in air around freezing, almost none of those "cools" made it into the wine cellar, although tons of cools were dropped into the wood room overnight.

Lessons learned: For low power, quiet air movement, and to reduce temperatu re exchange, a duct to a refrigerator would need to be significant diameter (I'll be replacing with mostly 6", and 4" at the complicated bendy parts), non-corrugated (straight wall), and seriously well-insulated duct. I thin k it could work, but it's not as straightforward as you would think.

[alireza8087t]

I think solution would be design of system like central heating in buildings in order to decrease expense of fridge with outdoor condenser

[gfretwell]

In the winter time why would you want to waste that heat outside and in the summer it is usually hotter outside than inside.

[trader_4]

These people must think that a fridge has a 1 hp motor running most of the time. I put a killawatt meter on a couple new ones, ~90W when running and they only run a fraction of the time. I could run that continuously here for 12 hours for 13 cents. With it cycling, it's a few bucks a month.

And what would having a split design, with the condenser outside cost? Both in added hardware cost and in installation? It's a really dumb idea.

[croy]

I've wondered about this for decades, although not seriously enough to go anyplace with it. But I think you're on a good track, and I think it will happen.

The worst thing about refridgerators in the USA is the Energy Star group pressuring folks to ditch their old, inefficient units and buy new ones... every week or so, apparently. And they are quick to destroy the old units, effectively eliminating the used appliance market, and forcing even the poorest folks to buy new.