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I, as well, have wondered over whether to run or walk through rain. As years go by, however, the question becomes increasingly moot. After all, it's only water.

But here is another question that I have pondered. We know that a household refrigerator removes heat from a relatively well-sealed interior and exhausts it to the environment, typically the kitchen. We also know that the refrigerator also produces heat by (very simply stated) converting electrical energy into mechanical energy.

I am convinced that if placed in a perfectly sealed environment, a refrigerator will heat that environment, and will heat it quicker with its door left open as the mechanical components will be required to work longer/harder.

But now, lets put our normal refrigerator back into our normal kitchen in a normal, average, everyday house, like perhaps yours or mine.

Here is the choice. All of the heat being given off by the refrigerator can either be simply allowed to vent into the kitchen (as is the case in every house I know of), OR, with the flip of a lever, all of that heat will be vented directly out of the house to the outside.

The question then becomes, what effects will these choices have on the heating and/or air conditioning (cooling) systems in the house.

In other words, should we put such a venting system on our refrigerators? Will it save us energy/money?

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All of the heat being given off by the refrigerator can either be simply allowed to vent into the kitchen ... , OR, ... vented directly out of the house to the outside.

... should we put such a venting system on our refrigerators?

Will it save us energy/money?

You have a heat pump. You're pumping heat from the interior of the fridge to the exterior of the fridge.

If you're choosing the part of the fridge's exterior that gets the heat, then

  1. If it's winter, and you want to heat the house, it will be beneficial to vent the fridge to the kitchen.
  2. If it's summer, and you want to cool the house, it will be beneficial to vent the fridge to the outside.
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You have a heat pump. You're pumping heat from the interior of the fridge to the exterior of the fridge.

If you're choosing the part of the fridge's exterior that gets the heat, then

  1. If it's winter, and you want to heat the house, it will be beneficial to vent the fridge to the kitchen.
  2. If it's summer, and you want to cool the house, it will be beneficial to vent the fridge to the outside.

your answer number one is inarguable. Answer number two is somewhat more complex.

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I am convinced that if placed in a perfectly sealed environment, a refrigerator will heat that environment, and will heat it quicker with its door left open as the mechanical components will be required to work longer/harder.

....

In other words, should we put such a venting system on our refrigerators? Will it save us energy/money?

Since you're aware refrigerators heat rooms and not cool them (whether or not the doors are open), it seems you're asking if the cost of a venting system will be compensated for by savings over the years in energy bills. There are a lot of factors to be discussed that are more suited for a non-brain teaser forum, so...

Off to "Others".

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Here's my two cents: the refrigerator should be kept in a small room with a window on the shady side of the lowest level of the house (e.g. the basement on the north side in the northern hemisphere) simply ventilated by a thermostatically operated reversible fan. The room should not be heated in winter and if it is in a cool basement, would not need air conditioning in summer. If you have no cool basement then the room with the refrigerator could be air conditioned in summer depending on whether the refrigerator alone or the refrigerator embedded in an air conditioning system have the more efficient net cooling effect (I'm not well-informed about this choice).

Best of all choices: trash your refrigerator and live a simpler life style. Keep a "root cellar" or ice house with ice blocks stored from winter to keep things cool the natural way. Live simply. Do without the energy/carbon squandering refrigerator technology and some of the unnecessary conveniences that it provides.

It's good to see a thread about environmental issues. We ought to have more discussion about sustainablility and our shameful legacy to our descendents. We ought to be concerned and aware, as the Native Americans are, for the welfare of the seventh generation and beyond.

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In other words, should we put such a venting system on our refrigerators? Will it save us energy/money?
My suggestion is to purchase an energy-saving fridge that emits the minimum amount of heat, from the exterior.

Usually, it's the older models that are wasteful and get hotter on the back of it. ;) Hence my answer, not to vent.

Edited by akaslickster
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My suggestion is to purchase an energy-saving fridge that emits the minimum amount of heat, from the exterior.

Usually, it's the older models that are wasteful and get hotter on the back of it. ;) Hence my answer, not to vent.

The question of whether to vent or not is in no way dependant upon the efficiency of the refrigerator.

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The question then becomes, what effects will these choices have on the heating and/or air conditioning (cooling) systems in the house.

In other words, should we put such a venting system on our refrigerators? Will it save us energy/money?

I would bet that it would'nt make that noticeable of a difference. Depending on the cost of having it installed, or if you would have to buy a new refrigerator to have it, it may not pay for itself for quite a while.

Summers on the way, you could test it out. Shut your refrigerator down for a day (time to go to outback) and your AC. The next day crank the AC, and see how long it takes for it to reach, or rather drop to, a certain temp. Then try it with your refrigerator running while the AC is off overnight, then see how long it takes to reach the same temp. Of course there are other factors involved,(also, probably want to do it on a couple of days with about the same outdoor temp as well) but if there is a significant difference in time, you might want to make a prototype of a venting system and bring it to Billy Mays :thumbsup: .

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... you might want to make a prototype of a venting system and bring it to Billy Mays :thumbsup: .

ARRRRGHHHHH! NO! ARRGHHHHHH! I thought I was safe from Billy Mays on this forum :blink::wacko::blink::wacko::blink::wacko::blink:

*runs out of the room screaming insanely*

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The question of whether to vent or not is in no way dependant upon the efficiency of the refrigerator.
Well, I believe it depends on your actual fridge and A/C plus heating system(s). Not a soul will be able to give you any specifics over the internet. At least with my idea, one should be better off. B)) Edited by akaslickster
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quote name='akaslickster' post='174700' date='Jun 5 2009, 04:21 PM']Well, I believe it depends on your actual fridge and A/C plus heating system(s). Not a soul will be able to give you any specifics over the internet. At least with my idea, one should be better off. B))

Edited by Brighterthan1000rocks
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*... peeking back in ...*

Is Billy Mays gone? Oh, whew, I can deal with Anthony Sullivan! :P

Brighter, it seems as though you are treating this as a riddle (i.e. you have an "answer" that you are trying to lead us toward by providing hints). Am I off base in this perception? Martini moved this thread to "Others" assuming it was a discussion on energy efficiency rather than a riddle; and that's how it appears (to me) the responders have been treating it. Please clarify.

(edit: punctuation)

Edited by seeksit
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Clarification (with my apologies)

This question occurred to me years ago when, as a youngster, I felt the heat coming from under the fridge on those hot September afternoons in Chicago. It seemed that this hot air worked against the AC in maintaining a cooler temperature in the house, and I wondered if venting that hot air outside would make it easier for the AC to maintain that temperature.

I wrote and posted ‘The Refrigerator Dilemma’ on New Logic/Math Puzzles, where I believe it belongs. The question has but one logical answer which can be both qualitatively and quantitatively defined. Bonanova is correct in saying that in winter we let the fridge help maintain the heat in the house. But the situation is different in the heat of the summer, when we normally use our AC to maintain a lower temperature inside the house than outside

A fridge produces heat, and that heat is contained in a volume of air that is inputted at ambient room temperature and exhausted at a higher temperature. To maintain constant ambient temperature, the AC must work incrementally to offset the additional heat in that volume of air. If we vent that air outside, the AC doesn’t have to deal with it, which makes venting seem beneficial. However, when a given volume of air is vented to the outside of a house, an equal volume of air must replace it by entering through cracks, vents, chimneys, from the outside. (Nature hates a vacuum.) If the air outside is warmer than the air inside, the AC will work harder to remove the excess heat in that volume of air.

Here is an example.

Assume the temperature inside the house is 70, and that temperature is to be maintained, and that the temperature of the air coming off the fridge is 80, and the outside air temp is 90. If we don’t vent the fridge, we deal with a volume of air 10 degrees warmer than the temperature we wish to maintain. If we vent the fridge, we are now dealing with the same volume of air (the replacement air) that is 20 degrees warmer than our target temperature.

So, if venting is beneficial at all, what are the circumstances?

The AC must deal with the excess heat contained in one of two volumes of air: either the air exhausting from the fridge if we don’t vent, or the replacement air if we do vent. These two volumes are identical, leaving the only remaining variable their respective temperatures. Thus, only if the heated air from the fridge is warmer than the outside air temperature is it beneficial to vent.

And who are Billy Mays and Anthony Sullivan?

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A fridge produces heat, and that heat is contained in a volume of air that is inputted at ambient room temperature and exhausted at a higher temperature. To maintain constant ambient temperature, the AC must work incrementally to offset the additional heat in that volume of air. If we vent that air outside, the AC doesn’t have to deal with it, which makes venting seem beneficial. However, when a given volume of air is vented to the outside of a house, an equal volume of air must replace it by entering through cracks, vents, chimneys, from the outside. (Nature hates a vacuum.) If the air outside is warmer than the air inside, the AC will work harder to remove the excess heat in that volume of air.

Here is an example.

Assume the temperature inside the house is 70, and that temperature is to be maintained, and that the temperature of the air coming off the fridge is 80, and the outside air temp is 90. If we don’t vent the fridge, we deal with a volume of air 10 degrees warmer than the temperature we wish to maintain. If we vent the fridge, we are now dealing with the same volume of air (the replacement air) that is 20 degrees warmer than our target temperature.

So, if venting is beneficial at all, what are the circumstances?

The AC must deal with the excess heat contained in one of two volumes of air: either the air exhausting from the fridge if we don’t vent, or the replacement air if we do vent. These two volumes are identical, leaving the only remaining variable their respective temperatures. Thus, only if the heated air from the fridge is warmer than the outside air temperature is it beneficial to vent.

akaslickster wrote:

Well, I believe it depends on your actual fridge and A/C plus heating system(s). Not a soul will be able to give you any specifics over the internet.

Your response:

Nature hates a vacuum, and it truly has nothing to do with the efficiency of your fridge, your heating or your cooling system.

That response was misleading. Surely a less efficient refrigerator works more and generates more heat. Not all of the heat exhaust from a refrigerator is what's being removed from the inside. Lots of it is produced by the compressor. An older style, less efficient compressor will generate more heat, so the answer does have something to do with the efficiency of the refrigerator since a less efficient one will be more likely to put air that's at a higher temperature than the air outside.

bonanova said:

1. If it's winter, and you want to heat the house, it will be beneficial to vent the fridge to the kitchen.

Your response:

your answer number one is inarguable.

It's not arguable that the temperature outside may be warmer than a refrigerators exhaust? How much insulating properties do the vent materials have and what's the final temperature of the exhaust by the time it reaches the outside air? Do we need to use a fan to help exhaust that air to outside? If we don't, will the heat buildup inside the vent attached to the refrigerator affect the life of the refrigerator? How much power might such a fan use?

Also, most air conditioners have the ability to switch from fresh air to recirculating, so your answer doesn't necessarily work. If it's in fresh air mode, you'll want to vent out any air that's warmer than the inside air (assuming the air conditioner is blowing air in at a faster rate, which should be the case with a refrigerator).

The question has but one logical answer which can be both qualitatively and quantitatively defined.

Absolutely not. How can we answer quantitatively when you supplied us no measurements?

We can't even answer qualitatively. Besides the objections I raised above (how much heat does the refrigerator put out, what's the average temperature in the Summer, etc.), how can we answer your question, "In other words, should we put such a venting system on our refrigerators? Will it save us energy/money?" without the answers to those questions and others? How much is the cost of installing and maintaining the venting system? How much does the venting system save us in yearly power bills? Will we make more putting the money set aside for the venting system in our IRA account than we would save in electric bills in a 5, 10, or 20 year period?

How much heat does a refrigerator put out, anyway? I guess we can assume the average temperature for the Summer months you mention might be about 78°F. Does a refrigerator put out in the neighborhood of 75°F or 88°F? And in what amounts? One cubic foot of exhaust at 88°F per hour or 10 cubic feet? We're going to need a lot more information to answer qualitatively and quantitatively.

And who are Billy Mays and Anthony Sullivan?

Google is your friend:

http://money.cnn.com/2009/04/03/magazines/...rtune/index.htm

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