Saturday, April 23, 2011

Admiral side by side Refrigerator, it leaks water?

The detail is for both frost free refrigerators and manual defrost refrigerators:---------------


The problem is that the drain hole in the drain pan under your evaporator coil is clogged up with gunk.

You simply need to unclog that drain hole so that the melt water from the defrost cycle drains into that tray underneath the refrigerator which the melt water is supposed to drain into. The one you say is devoid of water.

Here is a blog I wrote up years ago that explains how frost free fridges work. Read it and keep in mind that the drain hole in the evaporator drain pan on your fridge is clogged up. That will explain where the water is coming from.

Also, I wrote this for a person who didn't know the first thing about fridges, so it may seem too basic...

The mystery of your frost free fridge revealed:
or "What every owner of a frost free fridge should know":

The way to tell the difference between a frost free fridge and a manual defrost fridge is that a frost free fridge will have separate freezer and fresh food compartments, whereas a manual defrost fridge will have a freezer box at the top of the fresh food compartment. The fundamental difference between a "frost free" fridge and a manual defrost fridge is that a frost free fridge has an automatic method of defrosting itself.

In a manual defrost fridge the refrigerant evaporates and absorbs heat as it flows through the channels molded right into the evaporator box at the top of the fresh food compartment. Since the refrigerant is evaporating in those molded channels, the evaporator box will be the coldest thing in a manual defrost fridge, and that is where frost will accumulate. You defrost such a fridge by unplugging it or turning the thermostat to "defrost" or "off" and waiting for the frost on the freezer compartment to melt.

In a frost free fridge, there will be an evaporator coil which is hidden out of sight which serves the same purpose as the "freezer box" in a manual defrost fridge. The refrigerant evaporates in that evaporator coil, absorbing heat as it does, thereby making the evaporator coil very cold. There will also be an "evaporator fan" which sucks air through that evaporator coil and blows most of the cold air into the freezer compartment, and a little of it into the fresh food compartment. Some frost free fridges have adjustable baffles that allow you to set the proportion of cold air sent to each compartment. The reason why the freezer compartment gets colder than the fresh food section is because it normally has more cold air flow through it.

Every time you open the door of the fresh food compartment or freezer compartment of your fridge, you let some cold dry air out of your fridge and some warm moist air in. The moisture in the air you let in is what causes frost to form on the freezer compartment of a manual defrost fridge or the evaporator coils of a frost free fridge. Ice and frost forming on the evaporator coils of a frost free fridge reduce the efficiency of the fridge because they act as insulation and prevent heat transfer between the cold aluminum coils and the air the evaporator fan is circulating over those coils and throughout the fridge. And, of course, frost reduces the amount of air flow through the coils.

This "automatic defrost system" consists of three components: the defrost timer, the defrost heater and the defrost thermostat. These three components work together to melt the frost off the evaporator coil.

Let's look at each of the three components in the automatic defrosting system of a typical frost free fridge:

1. THE DEFROST TIMER:
Just like you have a timer in a clothes washer that controls the valves and motors at each stage of the clothes washing cycle, every frost free fridge will have a defrost timer. The defrost timer in a frost free fridge is much simpler than the timers in washing machines or dish washers because there are fewer things in a frost free fridge for the timer to control. The defrost timer's job is to shut off the fridge's compressor and evaporator fan (together) for about 20 to 35 minutes every 8 to 12 hours and divert the power to the defrost heater instead.

2. THE DEFROST HEATER:
The defrost heater is just an electric coil heater that's positioned close to the evaporator coils so the radiant heat melts the frost off the evaporator coils. The melt water then drips down and is carried by a sloping drip pan to a drain. A rubber hose usually running along the back of the fridge carries this melt water down into a receiving pan sitting on top of, or around, the usually warm compressor motor. The water is then re-evaporated back into the room by the waste heat from the compressor. You can redirect this melt water into a drain and use your frost free fridge to dehumidify your house a little.

3. THE DEFROST THERMOSTAT:
Once the frost is all melted off the evaporator coils, continued heating results in a rapid rise in temperature in the vicinity of the evaporator coils. The job of the defrost thermostat is to detect that temperature rise and break the circuit to the defrost heater, thereby preventing further heating and possible damage to the plastic and foam parts near it. (This is normally accomplished by simply wiring the defrost thermostat in series with the defrost heater.) Once the defrost thermostat breaks the circuit to the defrost heater, the fridge will then just sit there and do nothing at all until the end of the defrost cycle when the defrost timer shuts off power to the defrost circuit and restores power to the compressor and fan circuit once again.


Actually, not to put too fine a point on it, but once the defrost cycle is over, the defrost timer DOESN'T actually turn on the compressor and fan. That's because the fridge might not need any cooling right then. At the end of the defrost cycle, the defrost timer restores power to the fridge's thermostat (more correctly called a "cold control"). The thermostat then closes the circuit to the fridge's compressor and evaporator fan only if the fridge needs cooling.

In the rest of this post, the word "thermostat" will be used for both the cold control and the defrost thermostat, but it should be obvious from the context which thermostat is being referred to.

So, the defrost timer switches power between the defrost heater and the fridge's thermostat (or "cold control"), and the thermostat then inturrupts that power or allows it to flow to the compressor and evaporator fan simultaneously.

So, typically, both the evaporator fan and the compressor motor will both be running (or both be not running) at the same time. If the compressor is running, but you don't detect any breeze whatsoever in the freezer compartment with your hand (or by the smoke rising from a lit cigarette or piece of smoldering cotton string), then it indicates a problem with the evaporator fan not working, and therefore no cold air being blown into the freezer and fresh food compartments.

Similarily, if the evaporator fan is blowing air, but the compressor is not running, it could be a problem with the compressor motor, perhaps the starting relay which starts the compressor motor.

Having the compressor and the evaporator fan both off at the same time is normal. The fridge may be cold and the thermostat has shut off the cooling circuit. Alternatively, the fridge could be in a defrost cycle. However, if both the compressor and evaporator fan are off for what seems like an unreasonably long time, and the food in your freezer is starting to melt, then there's a good liklihood that the defrost timer is STUCK in defrost mode.

AND THIS IS WHERE I COME BACK TO THE SUBJECT AT HAND.

The defrost timer location will be different on every fridge, so you have to find out where it is on your make and model.

Defrost timers will have their output shaft exposed so that if you mark the position of the shaft on the timer with a felt pen, you can check it an hour or two later to confirm that the timer shaft is turning. Also, having the output shaft of the timer exposed allows an appliance repairman to manually advance the defrost timer to check the operation of the defrost heater and defrost thermostat to see if they're working. This is normally done by turning the output shaft of the defrost timer with a screw driver, but since you can damage the timer by turning that shaft backwards the screwdriver slot will be designed in such a way that the shaft can really only be turned in one direction with a screw driver.

If you ever notice that your frost free fridge has suddenly stopped working completely, it's worth advancing the defrost timer to see if the fridge is stuck in defrost mode. If you hear a "click" and the fridge comes back to life, then the problem was that the defrost timer was stuck, probably in the defrost mode. That tells you it's a good idea to replace your defrost timer before that happens again.

If, on the other hand, if the defrost timer is stuck in the "run" mode, or the defrost heater isn't working, the usual result will be frost forming around the cold air vents in the freezer compartment, and frost forming in your frost free fridges freezer compartment. In that case, advance the defrost timer until the compressor and fan shut off, indicating that the defrost timer is now diverting power to the defrost heater instead. Try manually advancing the defrost timer to perform several defrost cycles in a row to melt the accumulated frost. If doing that doesn't help, then the defrost heater is probably not working and needs to be replaced. Normally, a repairman will also replace the defrost thermostat at the same time as he replaces the defrost heater because the cost of the defrost thermostat is only 2 or 3 dollars. So, replaceing it at the same time as the defrost heater is mostly a matter of preventative maintenance. Those 2 or 3 dollars could save a $50 or $60 service call a few months down the road.

Finally, if you ever see water dripping from the roof of the fresh food compartment of your frost free fridge, the problem is that the melt water from the defrost cycle isn't draining away. Most often the problem here is that dirt has clogged the drain hole in the drip pan under the evaporator coils. There will normally be a cover of some type in the freezer compartment of your fridge. Removing that cover exposes the fan and evaporator coil (which is easily damaged because of all the thin aluminum fins covering it's surface). By poking a flexible (stranded) wire into the drain hole of the drip pan under the evaporator coil, you can usually unclog the drain hole and allow the melt water to drain away as it should.


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This is just a guide of how the Admiral side by side refrigerator works.