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HVC

04/07/2017 4:26 AM

Dear Colleagues, my question could seem weird - but I think the answers and advises could be useful for the internal designers. The question is: what is the effect of the surrounding/outside temperature to the location of a refrigerator? I have seen refrigerators positioned a few centimeters adjacent to gas cooker.

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#1

Re: HVC

04/07/2017 5:34 AM

The lower the temperature outside a refrigerator, the lower the influx of heat through the insulation into the interior. The lower the temperature outside the refrigerator, the more efficiently its condenser can dissipate heat from the interior. In short, the cooler the outside temperature, the less work the refrigerator has to do to maintain its internal temperature, and so putting it next to a source of heat is not optimal. Doing so makes it work harder to maintain its internal temperature, wasting energy.

In a more extreme case, if the outside temperature is the same as the temperature setpoint, the refrigerator doesn't have to run at all to maintain temperature. If it is colder outside than the temperature setpoint, the interior will eventually become as cold as the outside temperature without the refrigerator running and the contents may freeze, depending.

Conversely, if the outside temperature is the same as the condenser temperature when the refrigerator is running, it will not be able remove any heat at all from the interior no matter how long it runs, and ultimately the interior temperature will rise equal the outside temperature.

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#2
In reply to #1

Re: HVC

04/07/2017 7:45 AM

Thanks Andrew, I thought so. I`ve been having a problem with an interior designer who was looking at it from the flexibility point of view and ignoring the energy conservation bit of it.

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#3
In reply to #2

Re: HVC

04/07/2017 8:55 AM

Energy considerations aside, I would think it would also make sense from a purely convenience standpoint to have a stretch of countertop between the fridge and the oven, one possibly including a sink; a food-prep area, fridge on one side, oven on the other?

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#4
In reply to #1

Re: HVC

04/07/2017 11:50 AM

You are hitting on an interesting point that many people may not realize. If you have an extra refrigerator in your unheated garage, you can actually thaw out your freezer when the weather is cold.

Here's why. In most fridge/freezer combinations, the cooling cycle is controlled by the refrigerator portion. The freezer is cooled open loop. Usually the fridge gets opened more frequently than the freezer so it tends to warm first, and the set point of the fridge is more critical. It really doesn't matter much to the freezer contents whether the temperature in the freezer portion is 10 degF or minus 5 degF. 15 degF difference in the refrigerated portion could mean spoiled milk or frozen produce.

When the refrigerator calls for cooling (heat removal), the freezer portion evaporator gets the refrigerant first, cooling it open loop. What is left over goes the fridge evaporator. So once the freezer is done boiling off refrigerant, the fridge gets its cooling. Sometimes this is done with a single evaporator and there is a division of the cooled air where the majority of the air flow is dedicated to the freezer, cooling it open loop, and the fridge gets a smaller portion of the chilled air until it reaches its setpoint. (Those dials in the fridge sometimes adjust the dampers to 'tune' that cycle.) Newer fridges are probably more complex and may have separate cooling loops but who puts a new refrigerator in their garage for the beer?

So what that means is that if the temperature in the unheated garage drops below the refrigerated portion setpoint, the compressor is never run and the temperature in the freezer can rise to the ambient temperature of the garage thawing out those expensive roasts you have in there. Ask me how I know this.

What I do in the wintertime is monitor my freezer temperature and when it starts to rise, I will place a covered pot of hot water in the fridge to warm it up. I could probably do the same thing by putting an incandescent light bulb (always lit) in the fridge during the winter. Or if I really wanted to get crazy, I could put a thermal snap action switch (close on rise)

http://www.sensata.com/klixon/thermostat-precision-6786.htm

in the freezer that would heat the fridge with a 100 W light bulb when the freezer temperature gets above a certain point. But that sounds like a lot of work.

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#5
In reply to #4

Re: HVC

04/07/2017 12:06 PM

Exactly. Once the temp outside gets cold enough to where that thermostat stops regulating, the compressor doesn't run and so the freezer portion warms up to ambient. Some people who put a fridge in their garage or on a side porch put the old one out there when they get a new one. One which, because of its age, probably just has the one thermostat. Mum and dad did that and couldn't figure out why the freezer wasn't working when they had a cold spell. After that they got a chest freezer for the frozen stuff and just used the fridge portion in the other one for cold drinks.

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#6

Re: HVC

04/07/2017 12:28 PM

The layout of a commercial kitchen is all about efficiency of time and movement in preparing and serving food...insisting that the coolers be in a certain place relative to the stove and grill, is not a wise position to be in....leave it up to the chef....and cool the coils with auxiliary fans if necessary....but the exhaust along with the fresh air supply is usually sufficient for keeping air movement adequate...

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#8
In reply to #6

Re: HVC

04/08/2017 12:00 AM

And on some fresh air supplies there is added moisture which can help to reduce the cooling load on the refrigerators.

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#7

Re: HVC

04/07/2017 2:55 PM

Reduced cooling effect. That's the condenser side, meaning refrigerant must be able to transfer the carried heat through it. In return condensing the refrigerant into liquid phase, but since it can't (let's say to the point of extreme, where it still remains at most in vapor phase). it will drastically carried significant heat and evaporation is not possible at the evaporator since its already in vapor phase.

It's to some point like an overload effect when you turn on your cavalier air-condition in mexico in a blazing heat and full throttled air-con in the middle of a heavy traffic.

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