GE Monogram 48" side by side air circulation question

Seems like it's inevitable that the fridge will be emptied and defrosted; will then check all the air passages (including the return opening which as I see it is convoluted; see pic) and attempt to make a meaningful test of the evap fan.

@jayeff

"manuals specifies 6.3V for the rpm and not a variable one so I assume that it would be constant from the fan."

Don't see any reference to 6.3 anywhere in the doc. Attached is a pic of the J2 connector on page 26 of the PDF.

"correct the logic may be to keep the fan at the same speed regardless as it doesn't know what speed"

The manual says it defaults to high speed

"Check what voltage is seen on it."

Will do"

"Does the fan in the quick chill drawer fan work OK?"

Checked early on and it was working.

"Did you check the refrigerator door seals"

Tested ok a month or so ago; if they were leaking the so called vacuum we discussed previously would not be evident.

@jayeff

Found the page 30 J2 info.

I will confirm all the evap conductor voltages again including the blue wire on J2-1

Here are the readings with J2 plugged in and unplugged:

I have some comments about the readings; I'll get to them soon.

@jayeff

This issue has been very consistent with the deep freeze not occurring when the styrofoam is in place. This morning, for the first time with the temp settings at 0F & 37F, the freezer went to -9F and the fresh food was 36F.

Will use a bore scope to take a look inside the freezer. The only difference I'm aware of is that we've had a lot of rain recently and the humidity inside the house has risen above 60%. Seems like this points to the source of the problem being something other than air circulation; intermittent evap fan??? The damper was open and there was no obstruction. FF temp display seemed to coincide with the digital IR readings.

The old adage that I have found to be true seems applicable: "When something defies analysis, there's probably more than one thing contributing."

Your observation that the correct manual may help solve this, but my experience with the new "GE" is they promise to deliver and deliver nothing.

BTW, with J2 unplugged, there will be no readings available on the harness side; correct me if I'm out in space on that. :0)

Here's the response I got for the wiring schematic. My bad for not recognizing that it was not a GE organization and a commercial enterprise only interested in obtain your IP address tied to your home address and contact info... :0(

Hello Nick,

Thank you for contacting Bodewell, GE Appliances' new premium brand of support.  My name is Sancyrae, and it's my pleasure to assist you today.

 Before I can submit your wiring diagram please provide the required contact details below.

Mobile number

Residential address

Please also ensure the full model/serial number is provided. I look forward to hearing back from you soon.

 ''''

Please email us again if you have any further questions or concerns. I hope you have a wonderful rest of your day! Thanks for contacting us and please reach out to us again for any future related appliance needs.

Sancyrae

Email/Chat specialist, Bodewell

GE Appliances, a Haier company

And here is a new twist on the issue. Up until yesterday there was never an incidence of this issue when the damper conduit/extension styrofoam was not in place; as long as it remained off, the problem was kind of ok, except the the finished area of the FF section was not finished. Lights and ceiling panels were/are removed.

Then yesterday, the FZ temp showed to be -16F; previously the lowest temp recorded was -13f. This new temp occurred without the damper extension styrofoam in place which is also a first. Thinking about this left me a bit confused until I decided to check the opening (the damper door was open). Reaching in toward the FZ I found the opening to be round and not square and blocked by frost buildup by about 35%. After clearing the frost and within a few hours the FZ temp dropped some 5 degrees.

Have to assume this has something to do with humidity, but there hasn't be much rain recently, so it leaves me kind of stumped.

My review of the interior workings with a bore-scope was a bit revealing, but at the same time confusing. The evaporator was clear of ice on the front side just above the ice maker, but the back side looking through the damper opening was all white, apparently clogged with ice. Couldn't really get a good focus on it because of the angle.

Have to assume that the cause of all this is somehow related to the ice buildup.

Anyone have any thoughts?

TIA, Nick

The box is now empty, disassembled and at room temp and I believe the issue is the ineffectiveness of the defrost cycle, which over time causes a buildup of frost on the damper for the FF section. Perhaps other blockages that I have not checked for...

Performed some tests with ice on the Thermodisc with no definitive results. Instead of opening and closing, it registers a changing resistance value much like thermistor. Anyone know how to test this unit using ice cubes in a bowl of water? Attached is an online copy/photo of the part.

Found another difference between actual wiring and available schematics. The schematic shows the over-temperature thermodisc to be in series with the Calrod defrost heater wiring, but I find that both are wired directly to the board.

The original Thermodisc shows it to be L65-20F and the current replacement part shows it to be L140-30F (opens at 140F and closes at 30F). Seems like that's a better arrangement than the opens at 65F which would allow the evaporator to get hotter. Appreciate any help with that.

Looks like the issue is high humidity and a defrost cycle that is too short, causing a buildup of frost/ice on the evaporator over time. My thought is that the thermodisc could easily be replaced by a permanent jumper (like cutting the original termodisc off and soldering the ends together) thereby causing the defrost cycle to run for the full 35 minutes instead of terminating when the thermodisc opens at an arbitrary temp.

I say arbitrary because my test of a replacement unit indicates the open/close circuit does not reflect the parameters stenciled on the unit. The stated specs are 140 & 30, but my test indicates 108 & 65. It does not appear to be possible to accurately determine the cause and effect in this case.

Very curious about this part as a replacement for the original part which has a spec of 65 & 20. Some engineer must have determined that the 65 & 20 spec was, at least in part, the cause of the poor defrost capabilities of these units. BTW, the part fits a lot of GE boxes.

It can take weeks for the issue to reappear; I will try to post results in a few months.

Just now put the box back into service. Verified that the fresh food is circulating cold air and the freezer is getting cold; quickly... :0)

Discovered that the thermodisc insertion point has more than one place for it to be inserted; see this picture:

The ghost of the thermodisc is inside the circle (dark area where the original thermodisc was positioned) and apparently the engineer(s) wisely thought that the upper position may be too high bc that position is right next to the calrod, so they provided options. The upper position would definitely shorten the defrost cycle as would the specs on the original thermodisc (see above). Of course the attempt at balancing the heat/short timing was done to create the specs that to make it look efficient (failed). The bad news is that none of those concerns are referenced in the service document.

BTW, the picture was taken with a mirror as there is no room back there for focusing a camera. The reverse mirror image was straightened out with Photoshop and the fresh food wall is on the left in that picture.

We'll see how this goes...

None of the above corrected the deep freeze problem, that includes the replacement of the $300+ fresh food damper kit. Purchased that kit because the service doc suggested in two different places (once in the inline text and once in the text for the service mode guide) that to test that damper you simply had to cycle the power to the fridge and notice the damper door cycle through its operation. Neither the new or the original damper functioned correctly with those tests and they both operated in the same kind of odd way.

Turns out that the proper way to test the fresh food damper is as follows:

While manually holding both the freezer (close this door) and fresh food door switches closed, press the temp "+" key continuously until the display show "off". Then press "-" once to restart the unit and observe the damper cycle through open and close.

Now, both the original damper and the new damper both work properly which eliminates the cost of the $300+ damper kit.

The main board is not in question; this issue was present while the original main board was in service.

That leaves only humidity for me to fix, although I wonder about one of the thermistors???

Ordered a new freezer door gasket (it was deformed on the hinge side) and it will be here tomorrow.

More to follow...