[SIZE=3]I had a repairman out today to diagnose the problem with our freezer remaining cold while the fridge is warm. The coils in the freezer were heavily iced and there was frost in the area where the air is circulated to the fridge side. He thawed the ice/frost and tested several components in the freezer and in the back of the unit. He determined that the fan in the freezer, although still working, was not blowing enough cold air into the fridge. For a week prior to the warming problem we would clearly hear a loud noise coming from the water filter area in the fridge 1-2x per day that would last a few minutes and then quit. I asked if something in the fridge roof compartment could be causing the problem and he told me there was nothing in the fridge that would explain the noise or warming problem and that the noise was the fan going bad that could be heard in the fridge. While looking at the parts diagram on this site I noticed there are clearly a defrost module and thermostat in the fridge compartment that could be causing the noise and warming issue. How do I determine which part is the one that needs to be replaced?[/SIZE]
Here are your parts
http://www.appliancepartspros.com/partsearch/modelsearch.aspx?model=MZD2766GES
Here is a manual which should help with the repair.
http://www.appliancepartspros.com/partsearch/modelsearch.aspx?model=MZD2766GES
[COLOR="DarkRed"]
He thawed the ice/frost and tested several components in the freezer and in the back of the unit.[/COLOR]
Since he defrosted it has the noise disappeared?
Also were the evaporator coils plugged solid with ice/frost?
While looking at the parts diagram on this site I noticed there are clearly a defrost module and thermostat in the fridge compartment that could be causing the noise and warming issue. How do I determine which part is the one that needs to be replaced?
Not sure why you believe you have a defrost problem.
Is the unit now working OK?
If you have a defrost problem the unit will work OK for a couple days up to a couple weeks till the coils freeze up again.
You have to remove the cover inside the freezer so you can inspect the evaporator coils. If they are frosted/iced up to the point that the fan cannot pull air through them you have a defrost problem.
You then have to force a defrost cycle to determine if it is the heater/defrost thermostat or the adaptive defrost board that is the problem.
There is a damper assembly at the top back of the fresh food section that regulates the amount of cold air entering the fresh food section, perhaps this was the noise.
Note: That a slow or intermittent fan will cause the fresh food section to run warm as it forces cold air into the fresh food section.
Sometimes frost/ice can build up due to a defrost problem and can interfere with the fan.
Denman, thank you for your reply. I have further information below that hopefully will help further diagnose the issue:
He thawed the ice/frost and tested several components in the freezer and in the back of the unit.
Since he defrosted it has the noise disappeared? The unit actually worked as normal after the coils were thawed. The noise came back after three days and the coils have frozen over once again.
Also were the evaporator coils plugged solid with ice/frost? They were and are again.
While looking at the parts diagram on this site I noticed there are clearly a defrost module and thermostat in the fridge compartment that could be causing the noise and warming issue. How do I determine which part is the one that needs to be replaced?
Not sure why you believe you have a defrost problem. I am not convinced it is a fan problem because the noise to me is clearly not the fan.
Is the unit now working OK? It worked ok for three days. The fridge is now warm again and the frost buildup is back.
If you have a defrost problem the unit will work OK for a couple days up to a couple weeks till the coils freeze up again. That is exactly what happened.
You have to remove the cover inside the freezer so you can inspect the evaporator coils. If they are frosted/iced up to the point that the fan cannot pull air through them you have a defrost problem. They are so I guess I do have a defrost problem and not a fan problerm.
You then have to force a defrost cycle to determine if it is the heater/defrost thermostat or the adaptive defrost board that is the problem. What is the process for doing this? How will I know which component is the problem?
There is a damper assembly at the top back of the fresh food section that regulates the amount of cold air entering the fresh food section, perhaps this was the noise. Is this assembly underneath the plastic cover at the top of the fresh food section? I saw the part on the diagram. How do you remove the plastic cover without breaking a tab, etc? The repairman never took the cover off to inspect this area. He said nothing in the fresh food section could be the problem. I had my doubts which prompted my original post to the repair forum.
Note: That a slow or intermittent fan will cause the fresh food section to run warm as it forces cold air into the fresh food section.
Sometimes frost/ice can build up due to a defrost problem and can interfere with the fan. Should I still consider a fan replacement?
So the parts in play appear to be the fan, the thermostat, the adaptive defrost board and the damper assembly. What are your recommendations to complete the diagnosis? Thank you for your assistance!
Looks like I screwed up with the link to a service manual so will try again
http://appliancedigest.com/index.php?/files/file/480-16010154-maytag-refrigerator-service-manual/
You may have to join the site to download the manual but it is free and this is a very good site for manuals and other info for the appliance repair DIYer.
Does sound like a defrost problem so lets tackle that first.
In you unit you only have two parts in the defrost system as the heater includes the defrost thermostat (Item 12 in Section 4 of the parts).
When the coils are frozen up.
Manually force a defrost cycle see the manual. When the fans and compressor turn off, you are in defrost
Now check the defrost heater to see if it is on.
Be careful you do not want to burn your fingers.
If the heater is on then the defrost board needs replacing.
If not on.
Unplug the unit.
Remove the plug for the heating element/defrost thermostat combo from the wiring and measure it for continuity, usually around 20 ohms or so.
The other wire in the connector is a feed back to the defrost board.
Note: the defrost thermostat must be frozen as it opens just above freezing. Also inspect it, if it is bulged at all replace it even if it measures OK.
If both the above are OK then odds are the defrost board is toast.
If you do not own a meter, I would suggest you purchase a one. You can get a decent digital multimeter for under $20.00. You do not need fancy though it is nice if the leads are a couple feet long.
If it saves ordering one unnecessary part it has paid for itself and you end up owning a useful tool.
Most places will not let you return electrical parts so if you order it, you own it.
A couple things to watch when measuring ohms and continuity
- Always remove power from the machine otherwise you could blow your meter.
- Always disconnect at least one side of any device you are checking. This eliminates the possibility of measuring an alternate/parallel circuit path.
- When checking for closed contacts and continuity use the lowest scale (Usually 200 ohms). Then try higher scales. This scale is 0 to 200 ohms so if the device you are measuring is 300 ohms this scale would show an open circuit which it is not, you are just measuring outside the scale’s dynamic range.
There is a good STICKY at the start of this forum about it’s use.
Denman, thank you for your additional thorough follow-up. It seems very likely the defrost board is the issue. I would like to confirm using the process you suggest but need the instructions on forcing a defrost cycle. The manual link does not take me to my model and when I try to access the correct manual I am denied access even though I registered on the site. Could you list the steps or is it too involved? Thank you again!
— Begin quote from denman;403799
Looks like I screwed up with the link to a service manual so will try again
16010154 Maytag Refrigerator Service Manual - ApplianceDigest.com
You may have to join the site to download the manual but it is free and this is a very good site for manuals and other info for the appliance repair DIYer.
Does sound like a defrost problem so lets tackle that first.
In you unit you only have two parts in the defrost system as the heater includes the defrost thermostat (Item 12 in Section 4 of the parts).
When the coils are frozen up.
Manually force a defrost cycle see the manual. When the fans and compressor turn off, you are in defrost
Now check the defrost heater to see if it is on.
Be careful you do not want to burn your fingers.
If the heater is on then the defrost board needs replacing.
If not on.
Unplug the unit.
Remove the plug for the heating element/defrost thermostat combo from the wiring and measure it for continuity, usually around 20 ohms or so.
The other wire in the connector is a feed back to the defrost board.
Note: the defrost thermostat must be frozen as it opens just above freezing. Also inspect it, if it is bulged at all replace it even if it measures OK.
If both the above are OK then odds are the defrost board is toast.
If you do not own a meter, I would suggest you purchase a one. You can get a decent digital multimeter for under $20.00. You do not need fancy though it is nice if the leads are a couple feet long.
If it saves ordering one unnecessary part it has paid for itself and you end up owning a useful tool.
Most places will not let you return electrical parts so if you order it, you own it.
A couple things to watch when measuring ohms and continuity
- Always remove power from the machine otherwise you could blow your meter.
- Always disconnect at least one side of any device you are checking. This eliminates the possibility of measuring an alternate/parallel circuit path.
- When checking for closed contacts and continuity use the lowest scale (Usually 200 ohms). Then try higher scales. This scale is 0 to 200 ohms so if the device you are measuring is 300 ohms this scale would show an open circuit which it is not, you are just measuring outside the scale’s dynamic range.
There is a good STICKY at the start of this forum about it’s use.
— End quote