What the code means.
Taken from the manufacturers' own service documentation — not from guesswork. We only answer for the series we can verify, and we say so when we cannot. How the three makers differ inside, from the same manuals: side by side.
Look up your code.
Sub-Zero Built-In 600-2 Series — Code Reference
- 05 Refrigerator compartment thermistor open, shorted or erratic
- 06 Refrigerator evaporator thermistor
- 07 Freezer compartment thermistor
- 08 Freezer evaporator thermistor
- 20 Defrost under-heat with no voltage feedback at defrost start
- 21 Defrost overheat
- 22 No voltage feedback at defrost start
- 23 Defrost overheat with no voltage feedback
- 24 Defrost under-heat
- 30 Ice maker water valve energised beyond fifteen seconds
- 40 Excessive freezer compressor run
- 50 Excessive refrigerator compressor run
- EE Thermistor at the displayed location is open or shorted
- Sr Showroom Mode — cooling disabled by design, not a fault
Viking VCC3 Inverter — Flash Codes
- 1 One flash, compressor running — no fault detected
- 1 One flash, compressor off — no command from the control board, or an open thermistor
- 2 Two flashes — no signal reaching the inverter
- 3 Three flashes — open circuit in the compressor cable or a compressor winding
- 4 Four flashes — compressor or system electrical damage
- 0 No flash, compressor off — no input power, or the inverter has failed
Codes are not universal. The tables above belong to the series named and nothing else. Sub-Zero's later Classic, Designer and PRO units use different control boards, and other Viking models report differently. Check the model plate before trusting any code chart you find online — including this one. And a code tells you what the control registered, not what is broken: code 40 has been a dusty condenser as often as it has been anything expensive.
Knowing the code is not the same as fixing it.
A code narrows the search. It does not tell you which of four components in that circuit failed, and it does not distinguish a cause from a consequence — a defrost code often appears because a sensor failed weeks earlier, and replacing the heater fixes nothing.
It is also worth knowing that most of these circuits sit behind panels holding refrigerant lines, and that opening a sealed system legally requires EPA Section 608 certification. The useful thing you can do is write the code down. It arrives with you on the request, and we load the van accordingly.
Something stopped.
Tell us the code and what happened. We will call you back.