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Sub-Zero appliance error codes

Browse covered records for this brand by appliance type, code, and common symptom pattern.

Coverage status

Published records6

Appliance typesRefrigerator

Latest update2026-07-30

How Sub-Zero codes may appear

Sub-Zero's 600 Series support pages preserve two-digit displays such as 05, 06, 07, 20, 21, and 24, and also list compact EC forms such as EC05. Keep the leading zero and EC prefix when shown, then confirm the complete series, model, and serial because current and other legacy refrigeration families have separate controls and guidance.

Official display-code reference · Verified 2026-07-30

Source methodology Safety guide

Current themes

cooling temperature needs verificationfrost may be increasingrefrigerator or freezer warmingdefrost overheat warningdefrost underheat warningevaporator temperature sensor warning

Source types: official. Confidence levels: official.

Appliance types

Refrigerator

6 source-backed error-code records

0506072021

Codes

05Error code

Sub-Zero documents 05 on 600 Series refrigeration as a refrigerator-cabinet thermistor reading that is open, shorted, or repeatedly erratic.

06Error code

Sub-Zero documents 06 on 600 Series refrigeration as a refrigerator-evaporator thermistor signal that is open, shorted, or inconsistent.

07Error code

Sub-Zero documents 07 on 600 Series refrigeration as a freezer-cabinet thermistor reading that is open, shorted, or repeatedly erratic.

20Error code

Sub-Zero documents 20 on 600 Series refrigeration as a freezer-defrost underheat condition with missing feedback at defrost start.

21Error code

Sub-Zero documents 21 on 600 Series refrigeration as a defrost-overheat warning whose owner path depends on actual compartment temperature.

24Error code

Sub-Zero documents 24 on 600 Series refrigeration as a defrost-underheat warning with an owner response only near normal temperatures.