Login

u/jmmljltl328

r/ApplianceAdvice r/Appliances r/appliancerepair
Has Anyone Used a Mail-In Service to Repair a Sub-Zero Control Board?
▲ 2 r/appliancerepair

Has Anyone Used a Mail-In Service to Repair a Sub-Zero Control Board?

Hi! I hired a SubZero authorized shop to replace the control board for my 16 year old Sub Zero 611 to fix an evaporator fan issue. My old board part # was phased out so they installed a direct replacement part. However, the new board is giving me a control issue where the cooling cycles run for 3+ hours freezing everything in the fridge compartment.

The technician with Subzero tech support already spent weeks on this ... replaced boards 2x, verified board configuration (resistor cut-outs), replaced compartment & evaporator thermistors, pressure tests were within specs, no EC codes, ... All things point to a control issue from this new board.

I still have the old original board. My initial service call was to fix a warm fridge & frozen crisper drawers. The tech said that the control board malfunctioned and was delivering inadequate voltage to the evaporator fan. So, I am hoping this old board can be repaired (relay? capacitor?) to run my fridge with proper control logic.

I'd really appreciate if you can share your experience/recommendation with any vendors (UpFix, etc) for similar repairs. TIA!

Btw I am in Canada. Perfect if the shop is domestic, but I will ship internationally to get my old board repaired if it makes sense.

u/jmmljltl328 — 1 day ago
▲ 1 r/appliancerepair

Subzero 611 cooling cycle issues. Would appreciate advice.

Hi everyone,

My Subzero 611-3 got a new control board and the cooling cycle has gone bonkers. The board was checked that the right resistors were cut off to configure it for the model/SN.

I took some readings at the start and end of cooling cycles off the diagnostic. I also use my instant-read digital thermometer to temp a glass of water on the top shelf. After running for a few days, this is what I observed:

  • Cooling turns ON when r~56F and rE=38F (water temp~50F), evap fan+compressor ON for ~2 hours
  • Cooling turns OFF when r~22F and rE~10F (water temp~30F), evap fan+compressor OFF for ~2.5 hours

My setpoint is 38F. LCD display shows a constant “00 38”.

According to this SZ document, the cooling seems to be consistent with the logic that the cooling cycle will not start unless rE is above 38F. The rE readings recorded at the beginning of cooling cycles were consistently at 38F, and r readings got very high at that point. (Btw my fridge has a glass door so I can figure out when the fridge cooling starts/stops with paper streamer).

I’ve a couple of questions that I’d love to get answers on before the service company comes back:

  • Why does the cooling ON cycle run until r got down to 22F?  (setpoint at 38F)
  • Why does the off-cycle defrost take so long for rE to reach 38F? Could it be the fridge went so cold causing the evaporator a long time to defrost? What else can cause a defrost problem? (The evaporator looked ok with no excessive ice build up at the end of cooling cycle. Tech said frost pattern was ok too)
  • Does the LCD suppose to show the current r and F readings? My LCD shows a constant “00 38” except one time yesterday that it showed “00 23” when it timed out after my diagnostic readings.

Thank you very very much in advance!!

https://preview.redd.it/rfv274asx6eh1.png?width=613&format=png&auto=webp&s=71f9a3320ae3511837122a14e1d36df74146e4d8

 

reddit.com
u/jmmljltl328 — 1 month ago
▲ 3 r/ApplianceAdvice+1 crossposts

New control boards & thermistors didn’t fix my Subzero

My 16 years old Subzero fridge 611 is still not fixed after replacing with 2 new control boards & 2 new thermistors (r & rE) within the past 10 days.

A bit of background on my original service call … my evaporator fan in my Subzero 611 was not working. The top shelf was warm but crisper drawers frozen. Display showed “00 51”. A factory recommended service company came to repair it by replacing a new control board citing the board failed to deliver required voltage to the evaporator fan.

With the new board, the evaporator fan started working again. But I encountered the opposite problem of the fridge running way too cold with liquids frozen on all 4 shelves.

I had the company back & they replaced both thermistors in the fridge & another new control board. (He said it was calling for cooling even when “r” was 27F so he replaced the board just in case.)

Three more days have gone by, my problem remains the same. Liquids are still frozen even with groceries loaded to provide thermal mass.

I noticed the cooling cycle starts when my analog thermometer reads about 45F and goes until 23F (Set temp is 00-38). The evaporator fan & compressor run for 4-5 hours each cycle. This behaviour has been consistent since the first new board. This can’t be normal operation with such wide range, right?

I am pretty sure he cut the right resistors to configure the board for my model. I don’t know why the board is using such erroneous (but consistent) upper and lower temperature limits to run the cooling cycle.

I can’t expect the technician to stick around to monitor a whole cooling cycle. I am trying to understand what to look for to help with the diagnostic when he returns. I’d very much appreciate some advice here. TIA!

u/jmmljltl328 — 1 month ago
▲ 1 r/appliancerepair

New control board didn’t fix my Subzero Fridge

My sixteen year old Subzero 611GS wasn’t cooling (display showed 50F set at 38F), but my veggies in the crisper drawers were frozen. Freezer seems to work fine. Had a Subzero recommended company come out to repair.

His notes - “Refrigerator compartment

temperature high at time of service. Compressor runs and condenser is clear of debris and fan is running well. Evaporator fan is not activating when the door is closed, motor only receives 26V/ac, tested voltage at fan switch, 26V/ac.

Ordering new control board.”

They installed a new control board. Evaporator fan is working but the fridge is now running cold. The fridge is empty & I put half a small glass of water on each of the 4 shelves. They all froze to ice. The display shows 38F (set at 38F) but my old school fridge thermometer registers 27F.

Tech came out again, he checked all the thermistors, fan, etc. He said the evaporator fan has a “specific alignment” that was off. He fixed that but didn’t fix/replace anything else.

Again, all my glasses of water turned ice & the analog thermometer read 27F. (Fridge display shows 38F)

I will ask them to come out again. But I am hoping to get some help here to understand what the issue might be.

TL;DR Subzero 611 not cooling but crisper drawers are frozen. Tech said control board malfunctioned only delivering 24V to evaporator fan. New control board, evaporator fan works. New problem - fridge is too cold with liquids frozen. What could be the problem?

reddit.com
u/jmmljltl328 — 2 months ago