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REALLY random bleg
03 Sep 2008 12:56 pm
A friend has a freezer that ices up nearly instantly (it's a modern fridge, not one that SHOULD require defrosting). The refrigerator repairman checked the seal, confessed himself stumped, and wandered off. My guess, based solely on a long history with broken refrigerators and a hazy understanding of how the things work, is a problem with the compressor, presumably a hairline crack somewhere. But since I am an English major and don't really understand how that pretty electricity stuff works, I'm anxious to check my judgment against my vast engineering readership.
If the compressor has a crack, the refrigerant will be gone soon and you won't have to worry about icing.
De-icing is usually accomplished by vigorous air circulation. I would suspect a problem with the fans tasked to this. Alternatively, a source of warm outside air would cause icing (which is why the repairman checked the seal).
If the compressor doesn't work or works marginally then the refrigerator wouldn't get cold.
Self-defrosting refrigerators work by periodically turning off their compressor and running a heater on the cooling coil, which is the part that ices up. This can go wrong in five ways:
1: The heating element doesn't work and therefore doesn't remove the ice.
2: There is a thermostat on that heating element that is permanently set at something like 34 degrees. The thermostat detects when all the ice is melted and turns off the heater. Perhaps this thermostat is bad?
3: The control timer doesn't work and doesn't create defrost cycles.
4: When the ice melts, the water drains away. Perhaps the drain is clogged so the water doesn't drain away and it refreezes as soon as the defrost cycle is over.
5: Maybe the pipe to the ice maker leaks and sprays the cooling coil? This one is a long shot. In most refrigerators the ice maker valve is near the bottom so the pipe that runs inside the refrigerator is low-pressure, and the pipe is routed well away from the cooling coil to prevent freezing.
-dk
Wait, when you say 'ices up', do you mean formation of lots of ice inside the refridgerated box, or outside on the exchange coil/back/underside/whatever?
Since he was checking the seal, I'm assuming the former, which would be logical. Ice is water, and all that water has to come from somewhere...
Summarily, the refrigeration cycle is working, there is a source of moisture available (whether standing water in the unit or air from the outside), and the ice is not being melted. This should have been more than enough to get a competent refrigerator repairman on the right track, so your friend may have gotten the trainee.
Here are two things to check that may have nothing to do with the actual hardware, though:
1) Is your friend jamming either the back of the freezer or the back of the fridge full of things, especially near the top shelf, such that the air vent isn't free to circulate through the integral ventilation system? (This might hinder the defrost cycle and/or prevent humidity from escaping during the defrost cycle, so it immediately ices back up.)
2) Is your friend stuffing things in the door or the front of either unit such that door has a hairline crack, even though the seal is otherwise functional? (This might allow a continuous supply of exterior air into the unit, and/or prevent the device from reaching proper chilling temperature, so it runs the refrigeration cycle continuously and can't properly cycle through a defrost.)
Said friend has nothing in the freezer, because it's choked with ice, and becomes so almost immediately after defrosting; he defrosted it, and three days later it was covered.
My freezer has a tiny, tiny drain in the back.
My freezer iced up when, one day, this drain got plugged with ice. We emptied the freezer and got a turkey baster and some boiling water and flushed the drain with boiling water until it cleared (it took, like, 10 minutes). We cleaned the mess and haven't had a problem since.
So have him check the drain.
When I have an appliance problem, I usually head over to this website:
http://www.repairclinic.com/Home.aspx
For your specific problem("The freezer compartment is icng up"0, it redirects you to "Cooling is poor"-
http://www.repairclinic.com/0088_4_1.asp#Level1_3
Cooling is poor
For an overall understanding of how refrigerators should work, read about refrigerators in the How Things Work section of our website. A refrigerator or freezer that is cooling, but cooling poorly, may have a problem in one of several areas:
Evaporator coils
Condenser
Poor cooling is often the result of a heavy frost build-up on the evaporator coils or a condenser that is clogged with dust, lint, and dirt.
You're pressuring the crap out of the compressor lines. If there's a hairline crack in them, water somehow getting _in_, then getting from there somehow into your _freezer_, is not your biggest problem. So I'd discount that one. Look for a clogged drain...
he defrosted it, and three days later it was covered.
So the only reasonable diagnosis is a source of warm, humid outside air getting in somehow. Not even non-self-defrosting freezers ice up that quickly unless you leave the door open.
What Rob said; all that water is coming from somewhere, and it's presumably the air. Is this a freezer-only unit, or a kitchen-type with maybe a through-the-door ice dispenser?
If it's icing up that fast, there's plenty of water in even more warm air coming in, and a broken flap on an ice dispenser might do it...
Hi Megan:
More information please!
1. How much is "choked"? An inch of ice around the sides? More?
2. How often is the refrigerator under load (in other words, "on")? Most fridges have an audible sound when the compressor is running. Does it seem to be running abnormally often? (Just use your common sense)
3. Is there a fan anywhere inside the freezer compartment?
When I visualize "choked with ice", I'm thinking that over 20% of the internal volume is taken up by ice. To accumulate that much ice in three days is pretty incredible. That fridge should be running much more than normal. As Mike and Rob said, that water has to come from somewhere, most likely warm, moist outside air. There really aren't any other likely culprits.
The question is, where is the air coming from?
1. From the fridge. Many fridge/freezer combos, especially cheap ones, use cold air from the freezer to cool the refrigerator. The easiest way to do this is to put the freezer on top of the fridge, so cold air can just fall down. But there are other configurations, and maybe warm air from the fridge is finding it's way back into the freezer.
2. From the freezer-defrost cycle. There are two "defrost" cycles. De-frosting of the coils, and de-frosting of the freezer interior. De-frosting the coils is achieved by basically melting off the ice - the coils are heated, the water drains away (as suggested, check the drain). This is usually a tiny amount of water. Obviously, you can't defrost your freezer compartment that way, so instead, dry air is blown into the freezer, so that ice can sublimate into water vapor. This is why ice cubes in the freezer shrink over time.
What could be happening is that somehow, outside air is finding its way into the freezer de-frost cycle. Instead of blowing dry air to remove ice, it is blowing moist, warm air, creating a rapid ice buildup. Depending on how smart the fridge is, it might continually run the de-frost cycle, in a vain effort to get rid of the ice, while actually making the ice problem worse.
3. Failed seals, letting air directly into the freezer. But you checked for that.
4. Some combination of 1 & 2.
Based on this link here:
http://home.howstuffworks.com/question144.htm
This suggests that one of three things is broken:
If those things aren't working, then the mechanism for making the unit "frost free" will not properly engage.
But I could be wrong.
Based on what you said and instinct, I would say there is *no* flap on the water/ice dispenser or it is stuck open. A close second in the instinct department would be a pin hole in the ice maker hoses or valve, such that it is actually spraying a mist of water into the air. Of course, after 25 years troubleshooting stuff, I would have to say that instinct and guesswork are worth about the price of a cup of coffee. But at least it's a place to start.
On a side note, the real turning point in my engineering/troubleshooting career was realizing the following: You know that incredible 'Eureka' feeling you get when everything finally clicks into place and you know with absolute certainty the source of the problem and a golden glow suffuses your troubleshooting soul? That's just an emotion like any other, and it really doesn't have all that much to do with whether you've really found the solution.
More information:
I am told that in fact this is some weird modern italian job that does need defrosting every few weeks. But it's on overkill--I saw the freezer 3 days after defrosting, and it was way more than 20% of the available space taken up by ice.
There is no ice/water dispenser.
The refrigerator sits on top of the freezer unit.
>The refrigerator sits on top of the freezer unit.
That explains it. You need to replace the thelman bushing.
Yep, sounds like a bad thelman bushing. You might not need to replace it though; try just de-rotating it 90 degrees.
Most refrigerators can last between 1-2 weeks before defrost problems create visible symptoms.
If there is flaking frost in freezer, one can almost track from where it is forming - as to where it is coming from. Humid air leaking from the Fresh Food side, or door left slightly ajar, or an ice cube dispenser flap not closing are the most likely culprits.
Many people think they have defrosted a refrigerator when, in fact, they have not. It usually takes 12 - 24 hours with the refr turned off and the freezer door left open. Frost visible on the evaporator panel is the "tip-of-the-iceberg".
No idea what a thelman bushing is, but I highly suspect it's an inside joke for mechanics, like asking a urbanite to tip a cow. Of course, your blog probably just became the top hit for thelman bushing...
A quick google confirms altoids suspicion about thelman bushings.
Anybody want to go snipe hunting?
Either something's wrong with the Thelman bushing or the Johnson rod is on the fritz. Problem solved. Also, I never use the freezer since freezing ruins the taste of beer.
They don't have Johnson rods in Italian home appliances - that's illegal there.
Refrigerators/Freezers do NOT have either Thelman bushings OR Johnson rods.
Amateurs!!
As others have said, ice forming on the inside of a freezer compartment comes from humid outside air.
I've never seen a freezer compartment frost over as quickly as you describe.
Is the freezer in a dry location? Meaning is it not near a floor drain or a dishwasher or a leaking kitchen sink???? I assume the house it is in is air-conditioned so the relative humidity inside the house in general is "normal".
Some fridge/freezers have a "high humidity" setting you can switch over to in muggy weather.
That moisture is coming from somewhere...
If the unit is Italian are they sure that the lower section is actually a freezer? Sounds like it could be a gellato machine!!!
Awright wise guys go get a lefthanded monkey wrench and comb your hair...
Megan, If it frosts up as fast as you say, it cannot be just an air leak somewhere... It must be a major malfunction of the defrost system itself.
What I would suspect is that the heater is not coming on but that the fan is still blowing hot air in which is supposed to be flushing out the heated condensate coming off the coils.
I suggest you need to contact a store that sells this brand for a more experienced repair guy.
Or of course Sarah Palin could probably do this while nursing.
"Modern Italian job that needs to be defrosted every couple of weeks."
EVERY COUPLE OF WEEKS? WTF? Seriously WTF?
I loves me some expensive imported appliances for styling reasons, but jesus maria y joseph. Bad choice on the appliance. Funny thing is that many Euro appliance manufacturers have to make extra large versions of their appliances for the NA market. High-end customers outside of certain parts of Manhattan have adult size kitchens and want appliances to match.
The cause/solution has been mentioned above - there is a source of moisture somewhere, regardless of the door seal. But the real answer is to get rid of the labor intensive imported model and get a better fridge/freezer. They even make super expensive bottom freezer models. Of course the small version of US appliances is bigger than the large version of many euro firms, but that's whats awesome!
Just have to ask again, WTF would you buy a freezer you need to defrost every three weeks?
Stewie is right. The problem is humidity.
1. Air gets in.
2. The humidity in the air condenses as it cools and instantly freezes.
3. More air, more ice.
Freezers are not only sealed to keep the cold air in, they are sealed to keep the moist air out.
Somewhere in the system, outside air is getting into the frezer.
Awright wise guys go get a lefthanded monkey wrench and comb your hair...
Megan, If it frosts up as fast as you say, it cannot be just an air leak somewhere... It must be a major malfunction of the defrost system itself.
What I would suspect is that the heater is not coming on but that the fan is still blowing hot air in which is supposed to be flushing out the heated condensate coming off the coils.
I suggest you need to contact a store that sells this brand for a more experienced repair guy.
Or of course Sarah Palin could probably do this while nursing.
Hi Megan,
My freezer started icing up two months ago and it turned out to be the defrost heater.
That might be the cause of your friend's problem.
Then again, it could be the defrost thermostat or a faulty motor on the flap that controls airflow between the freezer and refrigerator. Now that I think about it, you might have a bad fan motor or a bad thermostat associated with the aforementioned flap.
To be honest, it depends upon the make and model of the refrigerator.
I suggest your friend visit the forum at partselect.com and see if others with the same refrigerator have this problem.
They also have handy parts diagrams which I used to replace the defrost heater myself.
That being said, I honestly believe your friend is S.O.L.
Meneghini, is that the Italian manufacturer?
Good luck finding parts or a qualified repairman for the Meneghini.
Call the manufacturer and see if they have any qualified repair services in the area.
Most appliance repair people have probably never even heard of Meneghini, nor would they have a repair manual or parts diagram.
It should make one think twice about buying eclectic major appliances.
Hi Megan,
My freezer started icing up two months ago and it turned out to be the defrost heater.
That might be the cause of your friend's problem.
Then again, it could be the defrost thermostat or a faulty motor on the flap that controls airflow between the freezer and refrigerator. Now that I think about it, you might have a bad fan motor or a bad thermostat associated with the aforementioned flap.
To be honest, it depends upon the make and model of the refrigerator.
I suggest your friend visit the forum at partselect.com and see if others with the same refrigerator have this problem.
They also have handy parts diagrams which I used to replace the defrost heater myself.
That being said, I honestly believe your friend is S.O.L.
Meneghini, is that the Italian manufacturer?
Good luck finding parts or a qualified repairman for the Meneghini.
Call the manufacturer and see if they have any qualified repair services in the area.
Most appliance repair people have probably never even heard of Meneghini, nor would they have a repair manual or parts diagram.
It should make one think twice about buying eclectic major appliances.
I lived the first 35 years of my life without the benefit of a frost free refrigerator... hey my parents spent a lot of money to get the biggest one they could find in 1948 - 7 cubic feet and a freezer big enough to hold a three ice cube trays on the top shelf and two half gallons of ice cream on the bottom shelf.
It's not terribly unusual to have to defrost every week or ten days in the dead of summer. The humidity is hovering around 100 percent and the air is hot. Chill that down below freezing and lots of water condenses out. Half an inch of ice in a few days is not unusual. All of it depends on how humid the room is and how often the door is opened.
Ice that forms from humidity is white, ice from liquid water entering the freezer tends toward clear.
Hi,
I had this. (An imported refrigerator which iced up quickly.)
There was a hole in the back of the freezer compartment where the refigeration pipes entered. The space around the pipes was supposed to be filled by a wad of gummy caulk which had become dislodged. It allowed air in.
I rearranged the caulk and it eliminated the icing. ...worth checking.
Then again, take a fridge that needs defrosting 'every couple of weeks' in Northern Italy and put it in a muggy, humid DC summer this may be what you get. If it's not in an air-conditioned space, maybe it really is just frosting up that fast. Keeping the door shut and the space as full as possible (less air!) might help if it's really working as designed...