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Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

5 recommendations

reply to aurgathor

Re: [Appliances] Is there a fridge that works correctly at any temperature?

The refrigerator/Freezer shuts off when the temperature outside is low enough to keep the inside of the Refrigerator lower than the thermostat is set. So when the Refrigerator temp is satisfied the unit does not run so the temp of the freezer rises to the ambient of the Refrigerator. It has nothing to do with the temperature of the compressor or lack of a compressor heater.

iknow_t

join:2012-05-03

2 edits
said by Jack_in_VA:

The refrigerator/Freezer shuts off when the temperature outside is low enough to keep the inside of the Refrigerator lower than the thermostat is set. So when the Refrigerator temp is satisfied the unit does not run so the temp of the freezer rises to the ambient of the Refrigerator. It has nothing to do with the temperature of the compressor or lack of a compressor heater.

the temperature of the compressor is what will determine how long it will last in such an environment. it won't last long without lubrication.. a simple fix to just get it working without regard to longevity is to make the inside light stay on with the door closed, and replace to bulb with a 25 watt or less bulb, this will make the compressor run long enough to keep the refrigerator cold..

Tig

join:2006-06-29
Carrying Place, ON
Reviews:
·voip.ms
reply to Jack_in_VA
said by Jack_in_VA:

The refrigerator/Freezer shuts off when the temperature outside is low enough to keep the inside of the Refrigerator lower than the thermostat is set. So when the Refrigerator temp is satisfied the unit does not run so the temp of the freezer rises to the ambient of the Refrigerator. It has nothing to do with the temperature of the compressor or lack of a compressor heater.

Agree. Every fall when I clean out the garage beer fridge I defrost the freezer and remove Popsicles etc to prevent the mess that happens when ambient temps are below the fridge thermostat setting. It's not a pretty site when things melt down in late October.
On the other hand, my 25 year old chest freezer in the garage has no problems whatsoever because it's thermostat is set for freezing and the compressor will run when it needs to.

Tig

join:2006-06-29
Carrying Place, ON
Reviews:
·voip.ms
reply to iknow_t
said by iknow_t:

the only thermostat that controls the compressor is the freezer thermostat, if it has one for the refrigerator compartment, that one only controls the air door that allows cold air from the freezer into the refrigerator compartment. the temperature of the compressor is what will determine how long it will last in such an environment. it won't last long without lubrication..

Interesting design, I've never owned one like that. At least not one that I've had in the garage or at the cottage.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

3 edits
reply to iknow_t
said by iknow_t:

the only thermostat that controls the compressor is the freezer thermostat, if it has one for the refrigerator compartment, that one only controls the air door that allows cold air from the freezer into the refrigerator compartment. the temperature of the compressor is what will determine how long it will last in such an environment. it won't last long without lubrication..

That's Baloney

I have a manual defrost fridge in my detached garage that has the old freezer in the top of the refrigerator compartment. When it's cold the refrigerator will not run and the Ice on the freezer will melt when the temperature is above 32 degrees. Keeps me from having to defrost it but it makes a mess in the fridge.

When the compressor does run it's start cold as there is no crankcase heater. It was here in 1989, compressor covered with water in 2003 and still operates. How much shorter lifespan should I worry about?

Through a feat of engineering genius, Refrigerator / Freezers are able to maintain two boxes (refrigerator and freezer) at two very different, but completely appropriate temperatures (0-ish and 40-ish), using a single compressor and thermostat. The problem is that they only do this well at nominal room temperature. The reason for this is that the thermostat controls only the temp of the refrigerator section. The cold air is directed through the freezer box, and a small amount is allowed to bleed into the fridge. By the time the fridge reaches 40 degrees, the freezer is near enough to zero (in the most common arrangement, the 'fresh food' or similarly labeled knob controls the thermostat, while the 'freezer' knob controls a damper between the two boxes). As the ambient temp drops, the compressor is called upon less and less, resulting in insufficient cooling in the freezer box, and the freezer temp begins to rise. When the ambient temp is below 40, the thermostat is happy and the compressor is never called into service. The result is that the freezer eventually settles in at ambient temp, too.


iknow_t

join:2012-05-03

1 edit
reply to Tig
delete.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Ok whatever you say. Have a good day


norbert26
Premium
join:2010-08-10
Warwick, RI
reply to Jack_in_VA
the temp in my childhood kitchen dropped to 40-42 for hours at a time all day long with no one home and no heat on. The frigidaire side by side freezer / fridge somehow always kept the freezer section cold . it was a frost free model made in the mid 70's.


pike
Premium,MVM
join:2001-02-01
Washington, DC
kudos:3
But it was only the 8 or so hours the heat was off while everyone was at work/school and the heat was turned back on for the other 16 hours of the day. And no one opened the freezer door during that period either so it's not too surprising the freezer maintained temperature during that period.


Tex
Premium
join:2012-10-20
kudos:2

1 recommendation

reply to Jack_in_VA
said by Jack_in_VA:

The refrigerator/Freezer shuts off when the temperature outside is low enough to keep the inside of the Refrigerator lower than the thermostat is set. So when the Refrigerator temp is satisfied the unit does not run so the temp of the freezer rises to the ambient of the Refrigerator. It has nothing to do with the temperature of the compressor or lack of a compressor heater.

This is the answer to the OP's issue.

Low ambient conditions can adversely affect the refrigerant and the system's ability to function properly. Commercial refrigeration systems (outside units) that are designed to operate in low ambient conditions use devices that keep the discharge pressures high enough to allow proper refrigerant feed to the evaporator coil metering device. In addition, these systems use compressor crankcase heaters to boil off any liquid refrigerant that migrates to the compressor during the off cycle. Compressors don't compress liquid and those that try to compress liquid can and do crater. Also, liquid refrigerant in the crankcase can cause oil to be flushed from the compressor leaving little to no lubrication to the mechanical components. Domestic refrigerator/freezer units are not designed with low ambient temperatures in mind. They may or may not operate as designed and doing so may shorten the life of the compressor.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

2 edits
My fridge in garage


Tex
Premium
join:2012-10-20
kudos:2
Domestic refrigerators/freezers are not my forte'. That's why included "may" in my last statement. I do know that during all my years in commercial refrigeration I have experienced compressors that have continued to function for years even after having been exposed to operational deficiencies that should have caused most compressors to fail. Conversely, I've seen relatively new compressors fail for unexplained reasons.


54067323

join:2012-09-25
Tuscaloosa, AL
said by Tex:

Domestic refrigerators/freezers are not my forte'.

Unlike commercial units, residential refrigerators/freezers units are I don't want to say undercharged, but they are minimally charged, and unlike the diagram above, the condenser is fed by the compressor to the top of the condenser where as the hot gas it dissipates heat and gradually travels down the condensor it as it changes from gas to, a vapor, and finally to a liquid and since a liquid being heavier than gas, it collects at the bottom of the condenser where it feeds a cap tube connected to the evaporator.

The reason they can get away with this is, in domestic units the heat load doesn’t vary a whole lot in comparison to commercial units, it is also why the majority of the "residental" units don’t use expansion valves, cap tubes are just fine.

As such, due to the small charge, the chances of liquid making it back to the compressor itself, is very remote and even if liquid did make it to the shell under very low ambient, the heat from the motor will flash it off within the shell.

As an expmple this is a small A/C compressor I sliced open, FWIW residential refrigerator/freezer compressors are built the same way.

The return line is not connected to the compressor, it dumps into the shell.


Return line entering shell


Then it flows through the windings.


Flows down on the windings


And finally enters the compressor near the sump.


Then into the compressor near the sump


Then back out through the side of the shell.


And back out the side to the condenser


54067323

join:2012-09-25
Tuscaloosa, AL

1 edit
reply to Jack_in_VA
said by Jack_in_VA:

The refrigerator/Freezer shuts off when the temperature outside is low enough to keep the inside of the Refrigerator lower than the thermostat is set.

By the way this is exactly what is happening, the compressor of a residential refrigerator is controlled by the thermostat in the food compartment, and as long as that food compartment is cooler then what the thermostat is set for, the compressor and therefore the refrigeration will not come on, and if it remains off long enough, the freezer will assume the same temperature as the food compartment defrosting whatever is in it.

Sorry, but is just how they work and the only real solution, if the OP cannot move the frig to a conditioned space, is to buy a small chest freezer, which by the way unlike a refrigerator/freezer will really freeze the food without that nasty frost the auto-defrost system causes.


54067323

join:2012-09-25
Tuscaloosa, AL
reply to Jack_in_VA
said by Jack_in_VA:

When the compressor does run it's start cold as there is no crankcase heater.

Internally with those little fractional horsepower compressors there is no need for a crankcase heater, the compressor doesn't sit in the oil which is very thin anyhow and they are built inexpensivly with tolerances that allow them to operate undamaged under a very cold startup.

On top of that if it is so cold the compressor will not spin up fully it will kick out the overload, which will reset and it all starts over and while this is happening the windings are heating up the internals, himm that sounds like what a crankcase heater does.

When the ambient temp is below 40, the thermostat is happy and the compressor is never called into service. The result is that the freezer eventually settles in at ambient temp, too.


What a concept, speaking from experence.


54067323

join:2012-09-25
Tuscaloosa, AL
reply to Jack_in_VA
said by Jack_in_VA:

My fridge in garage

Where's the beer???


Tex
Premium
join:2012-10-20
kudos:2
reply to 54067323
That looks like a rotary compressor. Not all residential refrigerator compressors are rotary. Reciprocating compressors have crankshafts, connecting rods, pistons and valves. I don't mean to be rude, but I don't need a lesson in the refrigeration cycle. Besides, you are not quite accurate in your description. Thanks anyway, though.


54067323

join:2012-09-25
Tuscaloosa, AL

1 edit
said by Tex:

That looks like a rotary compressor. Not all residential refrigerator compressors are rotary. Reciprocating compressors have crankshafts, connecting rods, pistons and valves.

But in the end they still take a gas at one pressure and change it to another pressure.

I don't mean to be rude, but I don't need a lesson in the refrigeration cycle.

I didn't go over the refrigeration cycle, I simply demonstrated how any possible liquid would be flashed off before it made it to the actual compressor.

Besides, you are not quite accurate in your description. Thanks anyway, though.

As in???


aurgathor

join:2002-12-01
Lynnwood, WA
kudos:1
Reviews:
·Frontier Communi..
reply to 54067323
said by 54067323:

Sorry, but is just how they work and the only real solution, if the OP cannot move the frig to a conditioned space, is to buy a small chest freezer, which by the way unlike a refrigerator/freezer will really freeze the food without that nasty frost the auto-defrost system causes.

Well, there are actually several solutions, and some are better than others.

I set everything to maximum, and the freezer started working again. Of course the next morning my milk was solid.... (I removed all my vegetables from the food compartment before and left them in an unheated room so no real damage)

I could also buy an outdoor rated fridge, which I'm considering for next year, even if I finish insulating my home.

For the time being, I think I'll just try to hack my fridge: there is already a 'heater' in the food compartment -- the bulb that turns on when the door is opened. I'll add an extra switch that allows me to keep the light on all the time -- 25W may not look like a lot, but I think it should be more than enough in an insulated enclosure.

--
.sig

lutful
... of ideas
Premium
join:2005-06-16
Ottawa, ON
kudos:1

1 edit
said by aurgathor:

I could also buy an outdoor rated fridge

You can also buy a residential model which has separate thermostats for freezer and fridge sections. Check the "climate class" rating - I mentioned common codes in previous post.

*** Whirlpool Gladiator garage fridge/freezer is rated from -17C to 43C. As close as you can get to the WAECO but much bigger in size.


54067323

join:2012-09-25
Tuscaloosa, AL

1 edit
reply to aurgathor
said by aurgathor:

I'll add an extra switch that allows me to keep the light on all the time -- 25W may not look like a lot, but I think it should be more than enough in an insulated enclosure.

Well that will probably be more than enough considering the garage heater is rated at 1/2 watt and it can do the job.