Leaving apartment for a few days - temperature questions.

[Jeff7]

I'm heading home for Christmas, and so my apartment will be utterly devoid of me for that time.
I intend to leave the heat running, primarily to keep the water in the pipes from freezing.
However, I also need to leave the refrigerator running. Does a refrigerator have a minimum temperature it needs to be kept at? I know some air conditioners will start to develop frost on the coils if the air temperature gets below about 60F. Are refrigerators at all like that?

In either case, what's a good temperature to leave the heat set at?

 

[userman]

Leave it alone!

 

[spidey07]

60 is fine. Don't worry about the fridge, they don't use much energy.

 

[Jeff7]

I'm not worried about the fridge's energy use, I'm worried about the coils frosting up and possibly causing damage.

 

[chusteczka]

Refrigerators are typically set at 33-36F.
Freezers are typically set at (-6) - (-1)F.
For a home refrigerator, leave the temperature settings as they are. If leaving for an extended time, then remove all the food, unplug the refrigerator, and stick something in the door to keep it open for airflow to prevent mold buildup.

For home heat, it is important to have enough heat to prevent the walls from contracting, which would cause them to crack. Like Spidey mentioned, 60F is fine. I would not want to drop the temperature below 55F but I am not certain on this exact number.

The hot water heater should have a "vacation" setting on the dial but this may not be high enough for winter freezing.

 

[Jeff7]

Um, I'm not asking about what to set the refrigerator at. I'm asking what to set the apartment's heat to.




Good point about the water heater, I wouldn't have thought of that. All I know about it is that it uses natural gas. No idea about a vacation setting or anything like that.

 

[userman]

Leave it at 60.

 

[SmoochyTX]

Make sure you unplug all of your other appliances and electronics just in case something catches fire! :Q

 

[RossMAN]

60

 

[spidey07]

Originally posted by: SmoochyTX
Make sure you unplug all of your other appliances and electronics just in case something catches fire! :Q

meh, that's what insurance is for.

 

[db]

60. Don't worry about the 'frige.

 

[FoBoT]

62F

 

[skyking]

the fridge will be fine, regardless. It's the plants that will suffer, if you have any.

 

[userman]

Originally posted by: skyking
the fridge will be fine, regardless. It's the plants that will suffer, if you have any.

What are you going to do to his ferns after he leaves?

 

[chusteczka]

If I understand this correctly, you are concerned with a low home temperature causing frost buildup on the evaporator coils on the outside back of the refrigerator.

Frost buildup on a refrigeration system's evaporator coils on the outside back of a refrigerator is independent of the home temperature setting. You could allow the home temperature to drop to below zero and a properly functioning refrigerator would not have frost buildup on the outside coils. (I suppose that would be because the refrigerator compressor would be shutoff due to the lower outside temperature cooling the refrigerator.) However, this is further true for a home temperature between 32F - 50F.

Such frost buildup would be caused by liquid freon that did not evaporate inside the freezer and is instead evaporating on the outside of the refrigerator and thereby absorbing the heat from the kitchen. This is a wasteful and possibly dangerous condition for a refrigeration system since the excess freon is not needed to cool the kitchen and any possible non-evaporated, liquid freon that reached the compressor would break it since liquids are not compressible.

The main cause for frost buildup on the outside coils in back of the refrigerator is typically too much ice buildup inside the freezer. This situation causes the thermal expansion valve (TXV or King valve) to open and deliver freon to the freezer. However, the ice buildup on the coils inside the freezer prevents heat transfer and the freon is unable to absorb heat from the freezer and expand within the freezer box. This problem is fixed by defrosting the freezer and removing the ice. Other causes for frost buildup on the outside coils in back of the refrigerator are too low of a temperature setting inside the refrigerator and a TXV that is stuck open and may need to be repaired or replaced.

 

[Jeff7]

Originally posted by: skyking
the fridge will be fine, regardless. It's the plants that will suffer, if you have any.

It's already suffering.
I brought a jade plant along with me. It's several years old, and its "trunk" is well over an inch in diameter.
Problem: the apartment's interior gets almost no sunlight at all. Back in summer, the plant got about 2 hours a day of direct sunlight. Now, the best it gets is the ambient light in the room.
Its old branches are loaded with dark green leaves. The new growth is all pale green, spindly stems, with roots sprouting out here and there.

I've got a light set up to keep my ball python nice and toasty during the day - it's a daylight type of bulb, so I've moved the plant near it. Hopefully the plant will at least survive until I finish college and move somewhere with light.
The plant is quite resilient. It was abused in the past - I could forget to water it for a month. Its leaves would just turn red and shrivel up. Water it, and it'd be back to normal in a few days.

(The ball python is coming home with me, and the light will of course be unplugged.)



chusteczka - what brought up my concern for the coils was my air conditioner. Awhile ago, I had it running during the day, but when night fell, the temperature really dropped, I think it was 55F outside. I heard the AC making funny noises, and went to check it out. The cold radiator was completely encased in ice. I don't know what exactly was making the noise, or if it did any permanent damage; nothing seems to have been affected in terms of functionality.
Its manual does say though that it shouldn't be operated below 60F.

Since refrigerators use similar technology, I was just concerned that this might be an issue, too.

But of course, pondering it more, I guess the cool coils are kind of meant to be surrounded by really cold air all the time.

 

[skyking]

Originally posted by: userman

Originally posted by: skyking
the fridge will be fine, regardless. It's the plants that will suffer, if you have any.

What are you going to do to his ferns after he leaves?

:evil:muwhaaaahaaaa!:evil:

 

[iroast]

65 if you have plants. Don't forget to set your boiler down to vacation (lowest possible)

 

[waffleironhead]

Originally posted by: chusteczka


The hot water heater should have a "vacation" setting on the dial but this may not be high enough for winter freezing.

When was the last time you had to heat hot water? Shouldnt it be a cold water heater?

 

[Jeff7]

Originally posted by: waffleironhead

Originally posted by: chusteczka


The hot water heater should have a "vacation" setting on the dial but this may not be high enough for winter freezing.

When was the last time you had to heat hot water? Shouldnt it be a cold water heater?

Don't make me take a waffle iron to your head.


And hey, sometimes hot water just might not be hot enough, you know? Besides, liquid water is at least 273K at 1atm. "Hot" is a relative term.

 

[waffleironhead]

Anyway... The fridge will be fine. I have a fridge and a chest freezer in my unheated garage and I have never had problems with icing up(read 10 below zero during winter).

Set the house to 60, leave the cold water heater alone!