106.55209400 Kenmore Elite: freezer OK, food section too warm, air-damper is open.

[t2d]

Model Number

106.55209400

Brand

Sears Kenmore

Age

1-5 years

Kenmore Elite Side-by-Side, Architect Series
Model: 106.55209400
2 years old

NOTE: I'm a handy homeowner and a half-bad troubleshooter but nothing more so please don't assume I know exactly what I'm talking about! ;-)

PROBLEM:
The Freezer Section is cooling properly (~3 degrees F) but the Food Section remains warm (~50F).

Other posts have indicated that this condition is due to a defective Air Damper unit.
http://www.applianceblog.com/mainforums/showthread.php?t=5614
http://www.applianceblog.com/mainforums/showthread.php?t=5437
This device was replaced under warranty in the first year to correct the food section from being over-cooled (opposite to the current problem).

However, I can see that the Air Damper's slotted gate is open and (with a flashlight) I see right through it into the freezer section. I used a small wooden stick to open it further and can insert the stick completely through the Air Damper, confirming it is open. Yet, I don't feel any cold freezer air flowing through it.

I suspected it might be a defective Evaporator Fan (no air pushed from freezer to food section) so I removed the metal panel and exposed the Evaporator Coils. The fan is running and, unless it is a variable speed unit, appears to be spinning normally at a reasonably fast rate (wouldn't want to stick my finger into it).

The Evaporator Coils are evenly coated with frost and are not a solid block of ice. However, I saw that the lower right corner had the most build-up of frost (enough to prevent you seeing between the coils). There's a heating element (a rod) under the evaporator coil assembly with a funnel-like tray underneath it to catch the drippings during a defrost cycle (my guess). The frost build-up encased about a third of the rod and was almost touching the funnel tray. I don't know if this is normal.

So the Air Damper is open, the Evaporator Fan is spinning, yet no cold air can flow into the Food Section. Something is blocking its flow.

Another post talked about a defective Defrost Timer thereby allowing an excessive build-up of frost that blocks the Air-Return (air returning from the food section). I can see the grille where the air exits the food section (on the divider wall, about one-third of the way up from the bottom). But where does it enter in the Freezer section? If it enters next to the over-frosted coils (lower right-hand corner) then maybe that explains why the air flow is impeded. Yes, maybe, no?

Am I on the right path here? Your help is appreciated!

PS
All our normally refrigerated food is now stowed in our unheated garage ... :-(

 

[Jake]

It sounds like you checked it all out good, but yet something is still clogging the air from flowing into your refrigerator section. I can't think of anything else to look for, you may need to call an appliance repair company out on this issue, very uncommon not to be able to locate the problem with everything you've checked.

Jake

 

[t2d]

Jake, thanks for confirming the problem is restricted air-flow.

When I arrived home yesterday, I was prepared to unplug the fridge and let it defrost completely ... maybe even help it along with a hair dryer. Imagine my surprise (vexation?) when it had already done that all by itself!

Yep, there was just a light coat of frost on the evaporator coils and the accumulation in the lower right-hand corner was all gone. I can now clearly see where the air-return from the food section enters the freezer ... it had been blocked by heavy frost. The food section is cold again.

I'd like to say "All's well that end's well" but I think I've only been chasing the symptoms and the root cause of the excessive frost build-up remains to be found.

Why would the refrigerator wait so darn long (> 3 days) before initiating a major defrost cycle? Maybe restarting it (at least twice during the three days) re-booted its control panel?

Does this model have an Adaptive Defrost feature (as in some KitchenAid units) where it adjusts its defrost cycle based on need and not a strict time period? If so, our home has been bone dry all winter (< 15% RH) and then we installed a central humidifier 2 weeks ago (now 35% RH). Did the sudden increase in humidity catch the Adaptive Defrost off-guard?

How is the defrost system programmed to operate on this model?

 

[Jake]

Yes, I have had to change the main control board on some of these with this issue, yes, the adaptive defrost is built-in to the main control board.

Here is the control board for your model:
8201659 Electronic Control Board


Jake

 

[t2d]

Thanks for the part number. I'll be keeping a close eye on the defrosting cycle and if it proves to be too infrequent I may just have to shell out for a new board.

Too bad it's not as cheap as a new defrost timer! Having a central control board is a neat concept but makes for an expensive repair when only one function fails!

 

[t2d]

Need your help again!

Jake,

Well, it appears there'll be no free lunch! A few days later and the air flow out of the diffuser has diminished. The food-section thermostat is set at 34F and my electronic thermometer reads 37.4F despite the fridge running non-stop for over 3 days.

In the freezer section, a quick peek through the lower vents of the evaporator shield shows signs of frost build-up on the evaporator coils. I can remove the shield to get a better view but I'm sure it's the same old thing happening again (frost is blocking the return air-flow into the freezer).

Is it possible to force this fridge to run an immediate defrost cycle? If so, how? Also, is it possible to reset the Adaptive Defrost to occur on a shorter-cycle (like 8 hours)?

 

[Jake]

Take off your kickplate below your doors at the bottom, you should see a service sheet that will tell you how to do it.

Jake

 

[t2d]

A few more questions.

Thanks, Jake! So obvious when you know where to look!

I was impatient so I manually defrosted the evaporator coils with a hair-dryer. The air-flow was back up to snuff and, within an hour, the food-section temperature dropped to 32.4F. Within three hours the compressor shutdown for a well-deserved rest.

I guess the real test is to force a defrost cycle by following the instructions:

1. Turn off the fridge using the control panel's ON/OFF button.
2. Press ON/OFF and the water-filter Reset button for 3 seconds.
3. Now the fridge is in Diagnostics mode at test #1.
4. Defrost is the sixth test, so push the Reset button five times until the water-filter display reads "6".

Correct me if I'm wrong, but this test exercises three things:

1. the control board's ability to activate the heater
2. the heater's ability to warm up and defrost the evaporator
3. the bi-metal's ability to open the circuit when the temperature gets warm enough

So if defrost works in diagnostics mode, it means the control board is at fault during normal operation because it waits too long between defrost cycles. Yes?

I'll be putting it to the test in a few days when the air-flow drops again.

 

[Jake]

So if defrost works in diagnostics mode, it means the control board is at fault during normal operation because it waits too long between defrost cycles. Yes?

Yes, thats correct.

Keep us posted on your test.

Jake

 

[Porkchop61]

I don't mean to hijack this thread, but I had the exact same symptoms as t2d had. I'm also very handy at troubleshooting electronics. Anyway, I had this same problem last year during the same type of weather, very hot and humid. I have the extended warranty, and of course the fridge side started cooling before the tech got to the house (3 days later). (BTW: This fridge is only two years old) So this time, the tech took the back panel off the freezer side and saw that I had a few rows of the evaporator coils plugged with ice (not frost). He said it was the bi-metal thermostat (without testing), and replaced it with a higher temperature unit. Does this sound like a reasonable fix for the defroster not running long enough? Glenn

 

[Jake]

Yes, as long as its not too much higher than the original.

Does it seem to be working like new again now?

Jake

 

[agt24]

I don't mean to hijack this thread, but I had the exact same symptoms as t2d had. I'm also very handy at troubleshooting electronics. Anyway, I had this same problem last year during the same type of weather, very hot and humid. I have the extended warranty, and of course the fridge side started cooling before the tech got to the house (3 days later). (BTW: This fridge is only two years old) So this time, the tech took the back panel off the freezer side and saw that I had a few rows of the evaporator coils plugged with ice (not frost). He said it was the bi-metal thermostat (without testing), and replaced it with a higher temperature unit. Does this sound like a reasonable fix for the defroster not running long enough? Glenn

I also have the exact same symptoms with 2015 Kenmore model number 253.70413414. And it is indeed hot in humid in Maryland this week. Can someone share the appropriate part number for the higher temperature replacement unit? I can't seem to find it online.