Food freezing in the refrigerator, by degrees.
Sub-Zero’s default settings on electronic controls are 38°F in the refrigerator and 0°F in the freezer, the temperatures it calls ideal for food. GE calls 37°F normal for a Monogram’s fresh-food side, and the FDA asks for 40°F or below. When food freezes anyway, the makers’ checklists point to the display scale, the room, a damper and the sensors.
On a Sub-Zero 600-2 or a Viking the setting moves one degree at a time, and Sub-Zero and GE both ask for 24 hours after any change. So the order below is deliberate: the numbers, the scale, the room, and only then the parts.
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What Temperature Should It Be Set At?
The makers’ figures sit within a degree of one another; the FDA’s is a ceiling rather than a target. Each row names the series its figures come from, and the last column is the first thing to check when it seems too cold.
| Normal setting | What the control allows | Worth checking first | |
|---|---|---|---|
| Sub-Zero Built-In 600-2 | 38°F and 0°F, Sub-Zero’s defaults on electronic controls | 34°F to 45°F refrigerator, −5°F to +5°F freezer, one degree per press | The scale: 1 to 7 in the refrigerator and −21 to −15 in the freezer means Celsius |
| GE Monogram ZIS side-by-side | 37°F fresh food, or “5” on a numbered control, which GE calls normal | 34°F to 45°F fresh food, −5°F to +6°F freezer | The room: after the settings, GE’s flowchart asks whether it is above 55°F |
| Viking VCRB5301 / VCRB5361 all-refrigerator | 38°F, the default | 33°F to 47°F; no freezer compartment | Whether MAX REF or FAST COOL is lit; each holds 33°F on purpose |
| US FDA, any refrigerator | 40°F or below, and 0°F in the freezer | No control range: a food-safety ceiling | An appliance thermometer: few controls show actual temperatures |
Series matter even within one maker: Sub-Zero’s Classic CL and Designer DET and DEC refrigerators stop at 42°F, not 45°F. The rating tag, not the badge, says which one you have. Where to find it.
Sub-Zero’s Own Six Checks
Sub-Zero publishes a short list for food freezing in the refrigerator, and asks for the same list when a freezer runs too cold. In its order:
- 01 Deal with any error code or message on the display first. the control
- 02 Confirm the settings; 38°F and 0°F are the defaults. the setting
- 03 Look at what is freezing, and where in the cabinet it sits. where
- 04 Clean the condenser if it has gone six months without it. the condenser
- 05 If the display reads extremely cold, check the scale and the relay. the display
- 06 Make sure the light diffuser is in place; it comes off when an overhead bulb is changed. the diffuser
Then allow 24 hours after any change. One case runs the other way: where the crisper drawers have their own fans, Sub-Zero says a setting above 35°F can run them excessively, and its advice for frozen produce there is 34°F. Its condenser intervals, answer by answer. What we repair on a Sub-Zero.
Is the display in Celsius?
Sometimes nothing is frozen and only the numbers alarm. Sub-Zero’s 600-2 service manual has a line for exactly that: a refrigerator showing 1 to 7 and a freezer showing −21 to −15 is a display set to Celsius and read as Fahrenheit. Those are the control’s normal ranges in the other scale, and Sub-Zero converts its defaults to 3°C and −18°C.
Changing it back is an owner’s job with one trap in it. On a 600-2 it works only in the first minute after the unit is switched on: hold the door-alarm bell key and the UNIT ON/OFF key together for five seconds, bell first, and °F or °C appears. Holding UNIT ON/OFF first, the manual warns, simply switches the unit off. A 600 Series without a bell key cannot change scale at all, and Sub-Zero publishes the steps for its other series separately.
Viking’s all-refrigerator can show Celsius too, with Fahrenheit as its default. If the scale reads °F and the numbers are still extreme, Sub-Zero’s other explanation, a stuck relay, is below.
Is the room below 55°F?
It sounds backward, a refrigerator too cold because the room is cold, but GE builds the room into its flowchart for this exact complaint. In the Monogram guide’s “Fresh Food Too Cold – Freezer Normal” chart, the first question after the settings is whether the room is above 55°F. Below that GE counts a low-ambient condition, and its next step is a talk about installation requirements, not a part.
Sub-Zero’s 600-2 manual draws the line higher, at 60°F, the bottom of the 60°F to 90°F room it performs best in. A built-in in a garage or an outdoor kitchen stands in whatever the night brings. What those rooms do to a built-in, at both ends of the band.
A Damper, a Sensor or a Relay?
Past the settings, the scale and the room, the makers’ documents name four ways a compartment ends up colder than asked, none of them inside the sealed refrigerant circuit.
- 01
On a Monogram, a damper that stays open
The fresh-food side is cooled by air the evaporator fan pushes through an electronic damper at the top rear of the compartment. GE’s too-cold chart asks whether that damper is closed; its damper chart then checks whether it is stuck and whether it moves the moment power returns, with the controls at 37°F and 0°F. It sits behind the light assembly and a foam cover: a technician’s check.
- 02
A sensor that reads warmer than the food
A control cools until its thermistor reports cold enough, so a sensor that misreads warm keeps it cooling. Sub-Zero’s 600-2 manual gives the sign: food 10° or more colder than the display points to the compartment thermistor, tested for 30,000 to 33,000 ohms at 32°F. GE’s chart tests the Monogram’s thermistors against a resistance table, checks the wiring, then replaces one out of range.
- 03
On a Viking, a sensor that has failed outright
Viking’s all-refrigerator errs cold when its sensor breaks. An open or shorted thermistor puts oPn or Shr beside REFRIGERATOR on the display, with five beeps once, and the control acts as if the compartment never reaches its cut-out temperature, so it keeps cooling. Either code is the one to read out on the phone.
- 04
On a Sub-Zero, a stuck relay
Sub-Zero’s other cause for an extreme reading is a stuck relay, which can run the compressor continuously. Its test is one an owner can make: switch the unit off at the control panel and listen. If it still runs, Sub-Zero says service is needed. Its other steps: a dedicated power source rather than a generator, five minutes off at the breaker, and 24 hours for the freezer to settle between −5°F and 5°F.
What each part does, and which ones are sealed-system work: the parts, in plain words. The visit is $119, waived in full when the repair goes ahead. What we repair on a Monogram.
On a Viking, is MAX REF on?
Viking put its coldest setting on a button. On the VCRB5301 and VCRB5361 all-refrigerators, MAX REF moves the set point to 33°F for four hours by default, and that 33°F cannot be adjusted. FAST COOL does the same for two hours. While either runs, its name is lit and a down arrow flashes until the cabinet reaches 33°F.
It ends when the time runs out, or sooner if MAX REF is pressed again, another mode is chosen, or HIGHER or LOWER is pressed. The four hours can be reset in the control’s service mode to anything from 1 to 20. A Viking at 33°F with MAX REF lit is doing what it was asked; one running cold with nothing lit and no code needs the thermometer test below, and its setting checked against the default 38°F. The panel is behind the door, above the cabinet interior, and stays locked until ACTIVATE CONTROLS is pressed. What we repair on a Viking.
How to Know It Is Really Too Cold
A display is not a thermometer in the food. The FDA notes that few controls show actual temperatures, and Sub-Zero’s own answers disagree about theirs, one calling it the actual temperature, another the set point. A 600-2 shows the set point for ten seconds after a key press, then an average that moves a degree a minute at most. A glass of water settles it.
- 01
Water stands in for food
Sub-Zero measures food, not air, with water standing in: a submersible thermometer in a glass of water covering the bulb, or vegetable oil in a freezer. No special thermometer is needed, and Sub-Zero recommends no brand.
- 02
The middle of the compartment
Halfway from front to back and halfway from top to bottom is where Sub-Zero puts the glass. If one shelf freezes while the middle reads normal, note which shelf.
- 03
Twelve hours, doors shut
Sub-Zero allows 12 hours for an accurate reading. GE’s Monogram guide works on the same span: at settings of 37°F and 0°F with no door openings for 12 hours, the fresh-food side should read 34°F to 42°F and the freezer −8°F to +6°F.
- 04
Then compare it with the display
Sub-Zero counts a swing of 5°F either way as normal, moved by door openings, humidity and the room. A glass reading 10° or more colder than a 600-2’s display is the row in its manual that names the compartment thermistor.
The FDA asks for the same habit: a thermometer in each compartment, checked often, against 40°F or below and 0°F. Colder than the setting is still the safe side of that line, which leaves time to find the cause properly.
Questions
What temperature should a Sub-Zero be set at?
Sub-Zero’s default settings on electronic controls are 38°F in the refrigerator and 0°F in the freezer, which it calls the ideal food-storage temperatures. A Built-In 600-2 accepts 34°F to 45°F and −5°F to +5°F, one degree per press, and Sub-Zero asks for 24 hours after any change before the result is judged.
Why is food freezing in my refrigerator when the setting is normal?
The makers’ documents name several. GE’s Monogram flowchart checks that the room is above 55°F, that the damper admitting cold air to the fresh-food side is closed, and the thermistors. Sub-Zero’s 600-2 manual ties food 10° or more colder than the display to the compartment thermistor, and Sub-Zero adds a stuck relay that can keep the compressor running. A Viking’s MAX REF holds 33°F on purpose.
My Sub-Zero shows 3 and −18. Is it too cold?
No. Those are Sub-Zero’s 38°F and 0°F in Celsius, and its 600-2 manual treats a refrigerator reading 1 to 7 and a freezer reading −21 to −15 as a display set to Celsius, not a fault. On a 600-2 with a bell key, switch the unit off and on, then within a minute hold the bell key and UNIT ON/OFF together for five seconds, bell first.
Does the display show the real temperature?
Not in a way that replaces a thermometer. The FDA notes that few refrigerator controls show actual temperatures, and a 600-2 displays an average that moves no more than a degree a minute. Sub-Zero’s method: a submersible thermometer in a glass of water, mid-compartment, read after 12 hours; vegetable oil in a freezer.
Sources
- Sub-Zero, refrigerator and freezer temperature settings: 38°F and 0°F as defaults and ideal food-storage temperatures, the ranges by series, 24 hours after a change, and checking °F or °C.
- Sub-Zero, food freezing inside the refrigerator and refrigerator or freezer too cold: the checks, in order. Its 600 Series bulb and diffuser answer: the diffuser comes off for a bulb change.
- Sub-Zero, extremely cold temperature on display: the wrong mode, a stuck relay, the listening test, −5°F to 5°F after 24 hours. Its 600 Series temperature unit selection: the first minute, five seconds, the bell key.
- Sub-Zero, food freezing in the crisper drawer: above 35°F, the drawer fans, and 34°F.
- Sub-Zero, measure temperatures in a refrigerator or freezer: water or oil, the middle, 12 hours, the display as set point. Its temperature fluctuations answer: 5°F either way.
- Sub-Zero Built-In (600-2) Series technical service manual (Job Aid #3758407, 2005): set ranges, one degree per key stroke and the display (p. 3-6); the displayed average (p. 3-9); temperature units selection (p. 3-16); the 60°F to 90°F room (pp. 8-13, 8-14); troubleshooting rows M and N (p. 8-14).
- GE Appliances, Monogram refrigerator too cold: 37°F, or “5”, as the normal setting.
- GE Consumer Home Services technical service guide 31-9091 (2002), Monogram ZIS360, ZIS420 and ZIS480: the damper (p. 14), the set point chart (p. 31), “Fresh Food Too Cold – Freezer Normal” (p. 54), “Damper Door Does Not Operate” (p. 59).
- Viking Preferred Service manual SMR-0022, VCRB5301 / VCRB5361 all-refrigerator, May 2012: the control panel (p. 6), FAST COOL and MAX REF (p. 7), °F and °C (p. 9), the 38°F default and one degree per press (p. 10), a failed thermistor (p. 11), MAX REF duration (p. 28), the 33°F and 47°F limits (p. 31), oPn and Shr (pp. 33–34), user defaults (p. 35).
- US FDA, refrigerator thermometers: cold facts about food safety: 40°F or below and 0°F, few controls showing actual temperatures, a thermometer in each compartment.
Written from these sources and reviewed on by Aphelion Appliance Repair, Phoenix. Settings, ranges and procedures belong to the series named beside them, and other series differ. Nothing here is a manufacturer’s instruction.
Read Next
- Refrigerator warm, freezer perfectWhy a warm fresh-food side on a Sub-Zero points at one of its two systems, not the whole machine.
- A built-in in the garage or the outdoor kitchenThe 60–90°F room the makers ask for, and what a garage does with it.
- Refrigerator parts, in plain wordsTwenty parts, what each does, and which are sealed-system work.
- Error codes, and what they meanSub-Zero 600-2 codes and Viking VCC3 flash codes, from the manuals.
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